And N times better than they are in charge of trouble, is to contradict themselves ah!

2010-03-22  来源:本站原创  分类:OS  人气:680 

Companies these days are busy with new products soon to be released, this does not have a client requests give them a test version, we present the condition is only Kongzhi 5 test platform of devices, Goodfellas, Zhuguangaile Tongxun bottom, I web control layer must change quickly and prospects, changing almost certainly go over our first ah!
Rack server it busy afternoon, sweeping from the room to an old guy, then installed linux install jdk, mysql, ready to run the project right, hey, the network connection is not on, check right away is the Internet, but also a change that is not out out, carefully view the IP address, or not!
For a charge over and asked me did not do a good job, I Jia, under the circumstances to the competent explanation, even ifconfig, are misspelled, in charge said something in the back "straight, you linux is so weak ah, you learn what??, with
ifconfig eth0 netmask up this command, under the temporary use of it! "
I am an angry ah really angry ah, how do so confused? ?
But I later found out, the temporary change IP, or it can not be used, in that respect from a sulking, then left in charge simply said, "You hurry up it!!! Ah!!"
Fast work, and came across I thought, Is the IP address conflict? ? ?
Then, off the test server, network, down a P2P Terminator, one by one check the company's IP, ha ha, indeed it was not!
It's that simple! ! ! ! !
Blame make life difficult for themselves and supervisors should not, ah, Blame my lazy not to re-set the bottom of the project configuration file!

The evening and then Bu Bu Shi Jin linux network commands!
Found a Daquan, and share it share

LINUX network traffic class commands Daquan

Function: chat with other users.
Syntax: ytalk [-isxY] [-h <host name of the IP address>] [user name ...]
Additional information: via ytalk instructions, you can chat online with other users, if you want to talk to other users of the host, the user name followed by its host name or IP address.
-H <host name of the IP address of> the specified remote host where the conversation object.
-I used to remind the sound instead of displaying information.
-S first in the command prompt window open ytalk conversation.
-X Close graphical interface.
-Y all have to respond yes or no question, must be in capital letters "Y" or "N" to answer.

Function: send a message.
Syntax: write [user name] [Terminal ID]
Additional information: can be passed through the write command message to another user login, when the input is completed, the type of information that the end of EOF, write command will be information to each other. If you receive information once the user not only the local host login, you can specify the terminal number to receive information.

wall (write all)
Function: send a message.
Syntax: wall [public notices]
Additional information: through the wall command to send information to each agreed to receive the public information terminal user, do not give their information content, the wall command will read data from the standard input device, and then the resulting data to all terminal users.

Function: UUCP host in the remote execution command.
Syntax: uux [-bcCIjlnrvz] [-a <address>] [-g <level>] [-s <file>] [-x <level >][-- help] [command]
Add that: uux UUCP host in the remote command or execute commands on the implementation of this machine, but when used in the implementation of the remote computer's files.
- Or the-p or - stdin read directly from the keyboard to execute commands.
-A <address> or - requestor <address> the implementation of e-mail address to send status information.
-B or - erturn-stdin status information displayed on the screen.
-C or - nocopy not copy the file to buffer.
-C or - copy the file to buffer.
-G <Grade> or - grade <level> specifies the priority file transfer operations.
-I or - config file specified uux profile.
-J or - jobid display job number.
-L or - link to files on the machine connected to the buffer.
-N or - notification = no regardless of any state, do not send e-mail to notify the user.
-R or - nouucico do not immediately start uucico service program, only the job sent to the queue, and then run.
-S <file> or - status <file> will complete state is saved as the specified file.
-V or - version display version information.
-X <level> or - debug <level> specifies debugging level.
-Z or - notification = error If an error occurs, Zeyi e-mail to notify the user.
- Help Show help.

Function: display the current status of UUCP.
Syntax: uustat [-aeiKmMNpqQRv] [-B <rows>] [-c <command>] [-C <command>] [-I <configuration file>] [-k <work>] [-o <hours> ] [-r <work>] [-s <host>] [-S <host>] [-u <user>] [-U <user>] [-W <Notes>] [-y <hour>] [-x <level >][-- help]
Supplementary note: implementation of uucp and uux instruction, will first work sent to the queue, then uucico to implementation. uustat can display, delete, or start the queue waiting for execution of work.
-A or-all show all of the UUCP work.
-B <rows> or - mail-lines <rows> with-M or-N parameters be used to specify the message to include the number of rows of information.
-C <command> or - command <command> Display and <commands> work.
-C <command> or - not-command <command> Display and <commands>-related jobs.
-E or - executions show only the work to be performed.
-I or - prompt for each job in the queue to ask whether the use of the work you want to delete.
-I <configuration file> or - config <configuration file> specified configuration file.
-K <work> or - kill <work> to delete the specified work.
-M or - status to delete all of the work.
-M or-mail to state information by mail to the UUCP administrator.
-N or - notify the state information of the work were submitted by mail to the user.
-O <hour> or - older-than <hour> show more than a specified number of hours of work.
-P or - ps shows the procedure for UUCP lock.
-Q or - list shows each remote host on the status of the work to be performed.
-Q or - no-list does not display the work.
-R <work> or - rejuvenate <work> to restart the specified work.
-R or - rejuvenate-all to restart all the work.
-S <host> or - system <host> show and <host> work.
-S <host> or - not-system <host> show and <host>-related jobs.
-V or - version display version information.
-U <user> or - user <user> display <user> work.
-U <user> or - not-user <user> display <user>-related jobs.
-W <Note> or - comment <Note> to put messages in the notes.
-Y <hour> or - younger-than <hour> show less than the specified number of hours of work.
-X <level> or - debug <level> specifies debugging level.
- Help Show help.

statserial (status ofserial port)
Function: Display the serial port status.
Syntax: statserial [-dnx] [serial port device name]
Add that: statserial can display the status of each pin, serial port used to determine whether it is normal.
-D to 10 decimal number to indicate the status of serial port.
-N Display only one serial port of the state after the end of proceedings.
-X and-n parameters is similar, but with 16 hexadecimal to represent.

Function: chat with other users.
Syntax: talk [user name] [Terminal ID]
Additional information: through the talk command, you can chat with another user online.

smbd (samba daemon)
Function: Samba server program.
Syntax: smbd [-aDhoP] [-d <debugging level>] [-i <range>] [-l <log file>] [-O <connection slot option>] [-p <port number>] [-s <configuration file>]
Add that: smbd process for the Samba server can share files and printers and other network resources for the Windows client programs related to access.
-A record of all the connections will be added to the record file.
-D <debugging level> recorded in event log file specified level of detail.
-D using this parameter, smbd process will service the way in the background.
-H Display help.
-I <range> specify the NetBIOS name scope.
-L <log file> specified log file name.
-O Every time you start, it will overwrite the original log files.
-O <connection slot Options> Set connection slot option.
-P <port number> set the connection port number.
-P is only used to test the correctness of smbd process.
-S <configuration file> specified smbd settings file.

smbclient (samba client)
Function: to access SMB / CIFS server, the client program.
Syntax: smbclient [Network Resources] [password] [-EhLN] [-B <IP Address >] [-d <debugging level>] [-i <range>] [-I <IP address>] [-l < log file>] [-M <NetBIOS Name >] [-n <NetBIOS Name >] [-O <connection slot option>] [-p <TCP The connection port >] [-R <Name resolution order>] [- s <directory>] [-t <server code>] [-T <tar Options >] [-U <user name>] [-W <Working Groups>]
Add that: SMB and CIFS protocols for the server, commonly used in Windows95/98/NT systems. smbclient allows Linux systems to access the Windows system to share resources.
[Network Resources] [Internet Resources] format for the / / server name / name of resource sharing.
[Password] enter the password required to access network resources.
-B <IP Address > send broadcast packets used in IP address.
-D <debugging level> recorded in event log file specified level of detail.
-E will be information sent to standard error output device.
-H Display help.
-I <scope> set NetBIOS name of the range.
-I <IP Address > specify the server's IP address.
-L <log file> specified log file name.
-L shows the server all the resources are shared out.
-M <NetBIOS Name > can use WinPopup protocol, the information is sent to the host specified options.
-N <NetBIOS Name > specified by the client to use the NetBIOS name.
-N do not ask for a password.
-O <connection slot option> to set the client TCP connection slot option.
-P <TCP The connection port > specify the server TCP port number.
-R <Name resolution order> to set the order of NetBIOS name resolution.
-S <directory> specified smb.conf is located.
-T <server character key "In what character set the server-side code to parse the file name.
-T <tar Options > backup server to share all files, and packaged into a tar file formats.
-U <user name> specify the user name.
-W <Working Groups> specify the workgroup name.

Function: dumping network traffic data.
Syntax: tcpdump [-adeflnNOpqStvx] [-c <number of packets>] [-dd] [-ddd] [-F <express file>] [-i <network interface>] [-r <packet file>] [ -s <packet size>] [-tt] [-T <packet type>] [-vv] [- w <packet file>] [output data column]
Add that: implementation of tcpdump command to list the specified network interface after the packet header, in the Linux operating system, you must be a system administrator.
-A try to the network and broadcast addresses to names.
-C <number of packets> received after the specified number of packets, it stops for dumping operation.
-D to the packet code compiled into readable format, and dumping to standard output.
-Dd to the compiled data packet encoded into the format of C language, and dumping to standard output.
-Ddd to the packet code compiled into decimal format, and dumping to standard output.
-E dump data in each column to display connection-level header.
-F with a digital display Internet address.
-F <express file> specifies the file containing the expression.
-I <network interface> using the specified section of the network send packets.
-L using the standard output buffer column.
-N not to convert the network address of the host name.
-N domain is not listed.
-O coding is not the best of the packet.
-P to prevent the network interface into promiscuous mode.
-Q Quick output, list only a few of the transport protocol information.
-R <packet file> from the specified file to read packets of data.
-S <packet size> to set the size of each packet.
-S with absolute rather than relative value associated with the number of TCP listed.
-T dump the information in each column does not display the time stamp.
-Tt dumping data in each column display the time stamp without formatting.
-T <packet type> to force a specified expression to set the packet transfer the packet type.
-V showing details of the instruction execution process.
-Vv more detailed instructions show the process of implementation.
-X with the hexadecimal code information listed in the packet.
-W <packet file> to packets of data to specified file.

shapecfg (shaper configuration)
Function: control the flow of network equipment.
Syntax: shapecfg attach [flow control device] [network equipment] or shapecfg speed [flow control device] [Bandwidth]
Additional information: Since the Linux-2.15, it will support the flow control function.
attach the flow control device combined with the actual network equipment.
speed set flow control device's external bandwidth.

Function: set or display serial port information.
Syntax: setserial [-abgGqvVz] [Equipment] [serial port parameters]
Add that: setserial can be used to set the serial port or display the current settings.
-A show for more information.
-B display summary information.
-G show the serial port information.
-G to the format of instruction list to display information.
-Q to display less information on the implementation.
-V display more information of implementation.
-V display version information.
-Z set before the first zero of all the tags.

Function: Samba server control.
Syntax: samba [start] [stop] [status] [restart]
Add that: samba as the script file, can start, stop Samba server, or return the current state.
start start the Samba server service.
stop stop the Samba server service.
Samba server status show current status.
restart Restart the Samba server.

pppstats (point to point protocol status)
Function: Display PPP connection status.
Syntax: pppstats [-adrv] [-c <number of times>] [-w <interval in seconds>] [web interface]
Additional information: Use pppstats PPP command allows you to connect to the network that the relevant information.
-A Display absolute statistics.
-C <number of times> Set return the number of times.
-D show the relative statistics.
-R display data packet compression ratio statistics.
-V Display VJTCP header compression efficiency statistics.
-W <interval seconds> set to display statistics interval.

Function: set the PPP connection.
Syntax: pppsetup
Supplementary note: This is the Slackware release containing the program, which has an interactive question and answer interface, allowing users to easily complete the PPP connection settings.

Function: close the ppp connection.
Syntax: ppp-of
Supplementary note: This is the Slackware distribution containing programs, allowing users to cut off the PPP network connection.

Function: Detection of the host.
Syntax: ping [-dfnqrRv] [-c <number of completed>] [-i <interval in seconds>] [-I <network interface>] [-l <Front loading>] [-p <Template style>] [-s <packet size>] [-t <Survival Values "] [host name or IP address]
Add that: implementation of ping command will Use ICMP protocol, Fachu request response Di Xin Xi, if the remote host's Wangluogongneng Meiyouwenti, Hui will be the information, so that Gai host Yunzuozhengchang.
-D using Socket's SO_DEBUG function.
-C <The number of times> to set the number of completed requests to respond.
-F limit of detection.
-I <interval seconds> send and receive information in the specified time interval.
-I <network interface> using the specified network interface sends packets.
-L <Front loading> set in the sending of the information required before the first packet sent.
-N only the output value.
-P <template style> set the style template to fill the packet.
-Q command does not show the process of implementation, at the beginning and end of the relevant information except.
-R ignore the normal Routing Table, the data packets sent directly to the remote host.
-R Record route process.
-S <packet size> to set the packet size.
-T <Survival Values "TTL setting the size of the survival value.
-V show command of the implementation process in detail.

Function: Display all UUCP remote host.
Syntax: uuname [-alv] [-I <configuration file >][-- help]
Add that: uuname displays UUCP remote host.
-A or - aliases Display alias.
-I <configuration file> or - config <configuration file> specified procedure profile.
-L or - local shows the local name.
-V or - version display version information.
- Help Show help.

Function: Display UUCP documentation.
Syntax: uulog [-DFISv] [- <rows>] [-f <host>] [-I <configuration file>] [-n <rows>] [-s <host>] [-u <user> ] [-X <level >][-- help]
Add that: uulog UUCP log file can be used to display the records.
-D or - debuglog troubleshooting records show.
-F <host> or - follow <host> with the-F parameter similar, but displays only the records related to the specified host.
-I <configuration file> or - config <configuration file> specified procedure profile.
- <Rows>,-n <rows> or - lines <rows> Show Log file, counting from the last specified number of rows value.
-S <host> show only records file, and specify the documents related records.
-S or - statslog statistical records show.
-U <user> or - suer <user> display only records file, and specify the user-related records.
-V or - version display version information.
-X <level> or - debug <level> set the debugging level.
- Help Show help.

tty (teletypewriter)
Function: display terminals to connect standard input file name.
Syntax: tty [-s] [- help] [- version]
Additional information: In the Linux operating system, all the peripherals has its own name and code, the code name of a special type of file stored in the / dev directory. You can check the implementation of the currently used tty terminal command file name.
-S or - silent or - quiet do not display any information, only to return a status code.
- Help-line help.
- Version display version information.

Function: display the data path between the packet to the host.
Syntax: traceroute [-dFlnrvx] [-f <Survival value>] [-g <Gateway >...][- i <network interface>] [-m <survival value>] [-p <Communications Port>] [-s <Source address>] [-t <service type>] [-w <timeout in seconds>] [host name or IP address] [data packet size]
Add that: traceroute commands allow you to track network packet routing means, the default packet size is 40Bytes, the user can be set.
-D use of Socket-level debugging capabilities.
-F <survival of Values "to set the first test data packet size of the survival of TTL values.
-F Do not leave broken bits set.
-G <gateway> set source routing gateway, set up to 8.
-I <network interface> using the specified network interface sends packets.
-I Use ICMP response to replace the UDP data and information.
-M <Survival Values "set the test packet size of the largest TTL value survival.
-N directly using IP addresses instead of host name.
-P <communication port> setting UDP transport protocol communication port.
-R ignore the normal Routing Table, the data packets sent directly to the remote host.
-S <Source address> set send packet local host IP address.
-T <service type> set test data packets TOS value.
-V show command of the implementation process in detail.
-W <timeout in seconds> set the return time to wait for the remote host.
-X enable or disable the correctness of the data packet inspection.

testparm (test parameter)
Function: Test Samba's settings are correct.
Syntax: testparm [-s] [configuration file] [<host name> <IP Address >]
Supplementary note: implementation of the Samba testparm command can simply test the configuration file, if the test result is correct, Samba permanent service will be able to load the correct settings, but does not guarantee that the operation was as expected as usual.
-S does not display the prompt to wait for the user presses the Enter key, direct listing on the definition of Samba service information.

Function: remote login.
Syntax: telnet [-8acdEfFKLrx] [-b <host alias>] [-e <out of character>] [-k <name>] [-l <user name>] [-n <log file>] [-S < service type>] [-X <certification form>] [host name or IP address <Communications Port>]
Additional information: telnet to open terminal stage of the implementation work, and log the remote host.
-8 Allows the use of 8-bit character data, including input and output.
-A remote system tries to automatically log.
-B <host alias> use the alias name specify the remote host.
-C does not read the user home directory inside. Telnetrc file.
-D start debugging mode.
-E <out of character> set from the character.
-E filter out of character.
-F the effect of this parameter and specify the "-F" parameters the same.
-F to use Kerberos V5 authentication, add this parameter to the local host's authentication data is uploaded to the remote host.
-K <name> to use Kerberos authentication, coupled with this parameter to the remote host using the specified field name, rather than the host domain name.
-K does not automatically log the remote host.
-L <user name> to specify the user login name of the remote host.
-L allows the output 8-bit character data.
-N <log file> specified file record information.
-R command to use user interface similar to rlogin.
-S <service type> set telnet connection required for IP TOS information.
-X assuming the host has to support data encryption capabilities, to use it.
-X <certification form> closing the designated certification form.

Birds (2001-03-01 16:36)
] [Back] [Forward
Function: display network status.
Syntax: netstat [-acCeFghilMnNoprstuvVwx] [-A <network type >][-- ip]
Additional information: Use netstat command allows you to learn the Linux system, the network situation.
-A or - all show all the connections in the Socket.
-A <network type> or - <network type> out of the network type of connection to the relevant addresses.
-C or - continuous continuous network status listed.
-C?-Cache show cache router configuration information.
-E or - extend display other relevant information network.
-F or - fib display FIB.
-G or - groups show multiple functional groups broadcast crew list.
-H or - help-line help.
-I or - interfaces display network interface information form.
-L or - listening display monitor in the server's Socket.
-M or - masquerade display fake network connection.
-N or - numeric IP address directly instead of through the domain name server.
-N or - netlink or - symbolic display of network hardware peripherals symbolic link name.
-O or - timers display timers.
-P or - programs show that the procedures being used Socket ID and the program name.
-R or - route show Routing Table.
-S or - statistice Display networking information tables.
-T or - tcp show the connection of TCP transport protocol.
-U or - udp show the connection of UDP transport protocol.
-V or - verbose display instruction execution.
-V or - version display version information.
-W or - raw protocol shows the connection of RAW.
-X or - unix this parameter results and specify "-A unix" parameters the same.
- Ip or - inet effect of this parameter and specify the "-A inet" parameter the same.

Function: streamlined version of getty.
Syntax: mingetty [- long-hostname] [- noclear] [tty]
Add that: mingetty apply to this machine on the login process.
- Long-hostname display the full hostname.
- Noclear login user name in asking not to clear the screen before the screen.

Function: set terminal of the write access.
Syntax: mesg [ny]
Additional information: the mesg y set, other users can write command will use the information displayed directly on your screen.
n does not allow users to pump information directly displayed on your screen.
y allows pump users to display information directly on your screen.

Function: display or set the network device.
Syntax: ifconfig [network equipment] [down up-allmulti-arp-promisc] [add <address>] [del <address>] [<hw <Network Device Type> <hardware address>] [io_addr <I/O Address > ] [irq <IRQ Address >] [media <network media types>] [mem_start <memory address>] [metric <number>] [mtu <bytes>] [netmask <subnet mask>] [tunnel <Address> ] [-broadcast <address>] [-pointopoint <address>] [IP address]
Add that: ifconfig can set the status of network devices, or display the current settings.
add <address> to set the IP address of IPv6 network equipment.
del <address> to delete the IP address of IPv6 network equipment.
shut down the specified network device.
<Hw <Network Device Type> <hardware address> to set the type of network equipment and hardware address.
io_addr <I/O Address > set of network devices I / O addresses.
irq <IRQ Address > set of network devices IRQ.
media <network media types> to set the media type of network equipment.
mem_start <memory address> set network equipment in the main memory occupied by the start address.
metric <number> specified in the calculation of the number of packets transmitted when the number to be added.
mtu <byte> to set the network device MTU.
netmask <subnet mask> set subnet mask of network equipment.
tunnel <address> establish the tunnel between the IPv4 and IPv6 communication addresses.
start up the specified network device.
-Broadcast <address> will be sent to the specified address as a broadcast data packet data packets to handle.
-Pointopoint <address> with the specified address of the network equipment to establish a direct connection, this model has a security function.
-Promisc off or start the specified network device promiscuous mode.
[IP address] IP address of the specified network device.
[Networking] The specified network name of the device.

getty (get teletypewriter)
Function: set terminal mode, connection speed and control lines.
Syntax: getty [-h] [-d <Configuration configuration file>] [-r <delay in seconds>] [-t <timeout in seconds>] [-w <waiting for the string>] [Terminal ID] [connection speed <Terminal Type> <Control Line>] or getty [-c <custom configuration file>]
Add that: getty command is UNIX like operating system starts the 3 steps that must be one.
-C <custom profile> specify custom configuration file, default / etc / gettydefs.
-D <Configuration configuration file> specified configuration profile, the default is / etc / conf.getty.
-H when the transmission rate is 0, the compulsory disconnection.
-R <delay number of seconds> set the delay time.
-T <timeout in seconds> set to wait for log time.
-W <waiting for the string> set the wait for a response string.

Function: send and receive faxes.
Syntax: efax [-sw] [-a <AT Directive >] [-c <Modem Properties>] [-d <Driver>] [-f <font file>] [-g <command>] [-h < fax Title string>] [-i <AT Directive >] [-j <AT Directive >] [-k <AT command>] [-l <ID>] [-o <options>] [-q < Error number>] [-r <file name>] [- v <Information type>] [-x <UUCP The lock file >] [-t <phone number> <fax>]
Additional information: support for Class 1 and Class 2 fax modem to send and receive.
-A <AT Directive > to specify the AT command to answer the phone.
-C <modem Attributes "to set the properties of the local modem.
-D <driver> specified modem driver.
-F <font file> using the specified font file to create a fax header.
-G <directive> if the received telephone data, the implementation of the specified commands.
-H <fax header string> specified string to the forefront of the title page.
-I <AT Directive > the modem into fax mode before sending AT commands to the modem.
-J <AT Directive > the modem into fax mode, send AT commands to the modem.
-K <AT Directive > fax mode before leaving the modem, send AT commands to the modem.
-L <Identification Key "set the machine ID modem.
-O <options> settings related to use non-standard modem options.
-Q <error number> receive a fax, an error page when the number of times over a specified time, to request retransmission.
-R <file name> in the receiving fax, will save each page into a file.
-V <Information type> to select the type of information printed.
-W Do not answer the phone, wait for OK or CONNECT signal.
-X <UUCP The lock file > use UUCP lock file format to lock the modem.
-T <phone number> <fax> to <phone number> the number to dial, and <fax> fax out.

Function: Set the network environment.
Syntax: netconfig
Supplementary note: This is the Slackware release containing the program, which has an interactive question and answer interface, allowing users to easily complete the network environment settings.

Function: Set the network function.
Syntax: netconf
Add that: netconf is the Red Hat Linux Linux distribution designed to adjust the settings of the program.

Function: Set the router.
Syntax: nc [-hlnruz] [-g <Gateway ...>][- G <The numbers point to>] [-i <delay in seconds>] [-o <output file>] [-p <Communications Port >] [-s <Source address>] [-v ...][- w <timeout in seconds>] [host name] [communication port ...]
Additional information: the implementation of this directive can be set router parameters.
-G <gateway> set router hop-way communication gateway, the most lost can be set to 8 oh.
-G <The numbers point to> point to set the source routing device, its value as a multiple of 4.
-H Online help.
-I <delay number of seconds> set the time interval for transmission of information and communication port scanning.
-L use the monitor mode, control of incoming information.
-N to use IP address directly instead of through the domain name server.
-O <output file> specified file name, the data transmission between 16 hex dump code into the file.
-P <communication port> set the local host using the communication port.
-R random designated local and remote host communication port.
-S <Source address> set send packet local host IP address.
-U use UDP transport protocol.
-V show command execution.
-W <timeout in seconds> set to wait for connect time.
-Z using the 0 input / output mode, only the use of port scanning traffic.

cu (call up)
Function: Connect to another system host.
Syntax: cu [dehnotv] [-a <communication port>] [-c <phone number>] [-E <out of character>] [-I <settings file>] [-l <peripherals code>] [-s <Connection rate>] [-x <debugging mode>] [-z <system host>] [- help] [-nostop] [- parity = none] [<system host> / <phone number>]
Supplementary note: This directive can be connected to another host, and dial-up terminal interface similar work, but also simple executable file transfer operation.
-A <Communications Port> or-p <Communications Port> or - port <communication port> using the specified communication port for connection.
-C <phone number> or - phone <phone number> dial the phone number.
-D into troubleshooting mode.
-E or - parity = even the use of double parity.
-E <out of character> or - escape <out of character> set from the character.
-H or - halfduple use half-duplex mode.
-I <configuration file> or - config <configuration file> to specify the configuration file to use.
-L <peripherals code> or - line <peripherals code> specifies an external device, as a connected device.
-N or - prompt waiting for user input when dialing phone numbers.
-O or - parity = odd use of a single parity check.
-S <connect rate> or - speed <connection speed> or the - baud <Connection rate> or - <Connection rate> set the connection rate, unit rate by Powell.
-T or - maper characters replaced by the CR LF + CR character.
-V or - version display version information.
-X <debugging mode> or - debug <debugging mode> use the debugging mode.
-Z <system host> or - system <System console> connected to the system host.
- Help-line help.
- Nostop close Xon / Xoff software flow control.
- Parity = none does not use parity checking.

arpwatch (ARP watcher)
Function: Monitor network ARP record.
Syntax: arpwatch [-d] [-f <log file>] [-i <Interface>] [-r <log file>]
Add that: ARP (Address Resolution Protocol) is used to resolve IP and network device hardware addresses. arpwatch to monitor regional network in the ARP packet and record, while listening to the changes to the report by E-mail.
-D start debugging mode.
-F <log file> settings are stored ARP recorded document, the default is / var / arpwatch / arp.dat.
-I <interface to> the specified ARP monitoring interface, the default interface is eth0.
-R <log file> to read from the specified file ARP records, rather than from the network monitoring.

apachectl (Apache control interface)
Function: can be used to control the Apache HTTP server program.
Syntax: apachectl [configtest] [fullstatus] [graceful] [help] [restart] [start] [status] [stop]
Add that: apachectl is slackware Apache HTTP server containing the script file, available for the administrator control server, but in other Linux, Apache HTTP server does not have this file.
configtest check the settings in the file syntax is correct.
fullstatus show the complete server status information.
graceful restart the Apache server, but will not interrupt the existing connections.
help Display help information.
restart Restart the Apache server.
start start the Apache server.
summary status display server status information.
stop stop the Apache server.

Function: modem communication program.
Syntax: minicom [-8lmMostz] [-a <on Or 0ff>] [-c <on Or off>] [-C <get file>] [-d <number>] [-p <Analog Terminal>] [ -S <script File >] [profile]
Add that: minicom is a very popular program PPP dial-up connection.
-8 Do not change any 8-bit coded characters.
-A <on Or 0ff> set terminal attributes.
-C <on Or off> set the color mode.
-C <get file> specified access file, and open access function at startup.
-D <number> to start or direct dial-up.
-L will not all characters are converted into ASCII code.
-M to Alt or Meta key as command key.
-M and-m parameters similar.
-O Do not initialize the modem.
-P <analog terminal> using the analog terminals.
-S open settings screen.
-S <script File > at startup, the specified script file.
-T Set the type of terminal.
-Z display the status bar at the terminal.
[Profile] minicom configuration file specified.


Function: IP dial-up connection.
Syntax: dip [-aikltv] [-m <MTU Number >] [-p <Agreement "] [dial-up script file]
Add that: dip can control the modem to dial-up IP's approach to building the external two-way connection.
-A asking the user name and password.
-I start the dial-up server capabilities.
-K to delete the implementation of the dip process.
-L specifies the connection you want to delete must be used in conjunction with the-k parameter.
-M <MTU Number > set the maximum transmission unit, default value is 296.
-P <Agreement "set the communication protocol.
-T dip into the command mode.
-V to display detailed information on the implementation.

dnsconf (dns configurator)
Function: Setting DNS server configuration.
Syntax: dnsconf [- deldomain <domain >][-- delsecondary <domain >][-- newdomain <domain >][-- set <host> <IP>] [- setcname <CNAME> <host>] [ - setmx <domain> <host >][-- setns <domain> <host >][-- unset <main>]
Add that: dnsconf actually symbolic links for the linuxconf to provide graphics mode of operation section for administrators to manage DNS server.
- Deldomain <domain> to delete the domain.
- Delsecondary <domain> to delete the secondary domain.
- Newdomain <domain> new domain.
- Set <host> <IP> new host records.
- Setcname <CNAME> <host> set <CNAME>.
- Setmx <domain> <host> specified domain mail host.
- Setns <domain> <host> specified domain DNS server.
- Unset <main> delete DNS records in a particular host.

Linux exit,

Name: cat

Permissions: All users

Usage: cat [-AbeEnstTuv] [- help] [- version] fileName

Description: The connection string to the file reached the basic output (screen or add> fileName to another file)

-N or - number from 1 to begin the line number of all output
-B or - number-nonblank and-n similar, but not code for blank lines
-S or - squeeze-blank lines when faced with more than two consecutive blank line, the substitution for the line of blank lines
-V or - show-nonprinting

cat-n textfile1> textfile2 to textfile1 file content with the line number in the file and enter textfile2
cat-b textfile1 textfile2>> textfile3 to textfile1 and textfile2 file content with the line number (without blank lines) after the content attached to textfile3

Name: cd

Permissions: All users

Usage: cd [dirName]

Note: change the working directory to dirName. One dirName representation for an absolute path or relative path. If the directory name is omitted, then the transformation to a user's home directory (that is, the directory where just login).

In addition, the "~" also means that the home directory, "." Is that the current directory where ,".." said the current directory location of the parent directory.

Example: jump to / usr / bin /:
cd / usr / bin

Skip to your home directory:
cd ~

Skip to the current directory on the two:
cd ../..

Command name: chmod

Permissions: All users

Usage: chmod [-cfvR] [- help] [- version] mode file ...

Description: Linux / Unix file access rights are divided into three levels: the file owner, group, other. Chmod can use to control how others access the file.

Into account:

mode: permissions string in the following format: [ugoa ...][[+-=][ rwxX ]...][,...], where u said that the owner of the file, g that with the owner of the file belong to the same group (group) who, o that other people outside, a three by key that is.
+ That increased authority - said the cancellation of privileges, = said the only set permissions.
r that can read, w that can be written, x said executable, X said that only when the file is a subdirectory or the file has been set off for the executable.
-C: If the file permissions has indeed changed, it shows the change action
-F: if the file permissions can not be changed and do not display an error message
-V: Display detailed information on permission changes
-R: the current directory for all files and subdirectories the same permissions to change (that is, the way one by one to recursively change)
- Help: Display Help
- Version: Display version

Example: Set the file file1.txt that anyone can read:
chmod ugo + r file1.txt

Set the file file1.txt anyone can read:
chmod a + r file1.txt

Set the file file1.txt and file2.txt the file owner, and his membership of the same group can write, but other people outside will not be allowed to write:
chmod ug + w, ow file1.txt file2.txt

Will set to only the file owner can do:
chmod u + x

The current directory and subdirectories of all files are set to any person may read:
chmod-R a + r *

Chmod can also be expressed in figures, such as chmod 777 file permissions
The syntax is: chmod abc file

Where a, b, c are each one respectively in that User, Group, and Other permissions.

r = 4, w = 2, x = 1
To rwx property is 4 +2 +1 = 7;
To rw-attribute is 4 +2 = 6;
To rx attribute is 4 +1 = 7.

chmod a = rwx file and chmod 777 file has the same effect
chmod ug = rwx, o = x file and chmod 771 file has the same effect

If using chmod 4755 filename can this program with root permissions

Command name: chown

Permissions: root

Usage: chown [-cfhvR] [- help] [- version] user [: group] file ...

Description: Linux / Unix is more than multitasking system, all files Jieyou owner. You can use chown to change the owner of the file. Generally, this command only by the system administrator (root) used by ordinary users do not have permission to change other people's file owner, no permissions to the file owner can change your set to others. Only the system administrator (root) have such rights.

Into account:

user: new file owner user IDgroup: new file owner's user group (group)-c: If the file owner has indeed changed, it shows the change action-f: if the file owner can not been changed and do not display an error message-h: only for the link (link) to make changes, rather than the link really points to the file-v: Display the owner to change the details-R: the current directory and subdirectories of all files make the same change of the owner (that is to recursively change the way one by one) - help: Display Help - version: Display version

The owner of the file file1.txt set users groups of users jessie:
chown jessie: users file1.txt

The current directory and subdirectories of all files users have by key groups of users set to lamport:
chmod-R lamport: users *

Name: cp

Permissions: All users


cp [options] source dest
cp [options] source ... directory

Description: copy a file to another file, or copy a few files to another directory.

The total 

-A possible state of the file, permissions and other information are to be copied according to the status quo.
-R If the source contains a directory name, Beijing and Taipei will be the directory of files copied to the destination sequentially.
-F file if the destination has the same name file exists, then the copy is deleted before re-replication.

Aaa copy the file (already exists), and named bbb:
cp aaa bbb

Will copy all of the C language program to Finished subdirectory:
cp *. c Finished

Name: cut

Permissions: All users

Usage: cut-cnum1-num2 filename

Description: Display each row counting from the beginning of the text num1 to num2.


shell>> cat example
this is test1
shell>> cut-c0-6 example # # print at the beginning of counting the first 6 characters
this i

Name: find

Usage: find
Instructions for use:

The file system found expression in the file listed. You can plunge the file name, type, time, size and powers, a combination of different information, and only will be fully consistent listed.

find path according to the following rules to judge and expression, the first in the command line - (),! majority before the path, after the expression. If the path is empty string then use the current path is empty string if the expression is used as the default expression  -print

expression can be used as many options there are 23 10, in which only introduced some of the most commonly used.

-Mount,-xdev: only check and specify a file system directory under the same file, to avoid listing the files in other file system
-Amin n: n minutes in the past had been read
-Anewer file: File file later than had been read the file
-Atime n: in the last n days, the files had been read
-Cmin n: n minutes in the past been modified
-Cnewer file: the file than the file file update
-Ctime n: n days in the past been modified files
-Empty: empty file-gid n or-group name: gid or group name is the name n
-Ipath p,-path p: path name of the line p file, ipath will ignore case
-Name name,-iname name: file name of the line name of the file. iname ignore case
-Size n: the file size is n units, b on behalf of 512 byte blocks, c that number of characters, k that kilo bytes, w is 2 bytes. -Type c: file type is c files.
d: directory
c: Font installation files
b: block device file
p: anonymous storage column
f: general file
l: symlink
s: socket
-Pid n: process id is n files

You can use the () to separate algorithms, and use the following operators.
exp1-and exp2
! Expr
-Not expr
exp1-or exp2
exp1, exp2

Under the current directory and its subdirectories extension file name is c all the files listed.
# Find.-Name "*. c"

The current directory and all subdirectories under it of its normal file list
# Find.-Ftype f

Under the current directory and its subdirectories for all the last 20 minutes, the updated file list
# Find.-Ctime -20

Name: less

Permissions: All users


less [Option] filename

less function and more are very similar, and both can be used to browse the contents of text files, different is less allows users to scroll back to view the part has been seen, and because less is not enrolled at the beginning of the entire file into the Therefore, in the event of a large file is opened, than ordinary text editors (such as vi) to the quick.


Command name: ln

Permissions: All users

Usage: ln [options] source dist, which option of the format:
[-BdfinsvF] [-S backup-suffix] [-V (numbered, existing, simple)]
[- Help] [- version] [-]

Description: Linux / Unix file system, there is a link (link), we can file it as an alias, but a link can be divided into two types: hard link (hard link) and the soft link (symbolic link), hard link means that a file can have multiple names, but the way the soft link is created a special file, the contents of the file points to another file location. Hard links exist with a file system, and soft link it across different file systems.
ln source dist is to generate a link (dist) to the source, for the use of hard links or soft links by the parameters.

Either hard or soft links do not link the file will copy the original, it will only occupy a very small amount of disk space.

-F: when the first link with the file name with the dist file delete-d: hard link allows the system administrator own directory-i: Remove and dist in the same file name of the file first to ask-n: carrying out soft link, the dist as a regular file-s: soft link (symbolic link)-v: display the file before the link name-b: in link will be overwritten or deleted files to back up - S SUFFIX: will backup all files with the suffix SUFFIX-V METHOD: the specified backup mode - help: Display Help - version: Display version

Yy will produce a file symbolic link: zz
ln-s yy zz

Yy will produce a file hard link: zz
ln yy xx

Name: locate

Permissions: All users approach: locate [-q] [-d] [- database =]
locate [-r] [- regexp =]
locate [-qv] [-o] [- output =]
locate [-e] [-f] <[-l] [-c]
<[-U] [-u]>
locate [-Vh] [- version] [- help]
so that users can very quickly locate the search for a file system, whether the file specified. The method is first to establish an all files within the database name and path, then when looking for it, just check on this database, rather than being a real in-depth file Xitong.

In the general distribution among the creation of a database are placed in contab in automatically. Generally only used when users use

# Locate your_file_name the pattern on it. Parameters:

Establish a database,-u will be at the root,-U, you can specify the start position.

Will be excluded from the search scope.

If it is 1. Then start in Safe Mode. In safe mode, the user will not see the file permissions can not see. This will slow down the beginning, because the need to actually locate the file permissions on the file system to obtain information.

To exclude a particular file system, such as to the reason we did not make proc file system files on the database.

Quiet mode, do not show any error message.

Up to display output.

Use regular expressions to do search conditions.

Information on the name of the specified stock.

Specify the path to the database

Auxiliary information display

Show more information

Display program version information Example:

locate chdrv: find all files called chdrv
locate-n 100 a.out: find all files named a.out, but most only display 100
locate-u: create database

Name: ls

Permissions: All users

Usage: ls [-alrtAFR] [name ...]

Description: Displays the contents of the specified working directory (listed in the current working directory containing the files and subdirectories).

-A show all files and directories (ls pre-determined file name or directory name starts with "."'s As hidden and will not be listed)
-L In addition to the file name, the file will type, permissions, owner, file size and other information set out in detail
-R will display the file in reverse order (initially in alphabetical order)
-T time the files listed in the order in accordance with established
-A with-a, but not out "." (Current directory) and ".." (parent directory)
-F file name in the list, add a symbol; such as executable file is a "*", the directory then add "/"
-R, if a directory with files, the following are listed in order of the files Beijing and Taipei

Lists all the current working directory name is s at the beginning of the file, the more the more the back of the new row:
ls-ltr s *

The / bin directory all of the following directories and file details are listed:
ls-lR / bin

The current work directory list of all files and directories; directory in the name added "/" after the name of the executable file in a "*":

Name: more

Permissions: All users

Usage: more [-dlfpcsu] [-num] [+ / pattern] [+ linenum] [fileNames ..]
Description: like cat, but will display a page-by-page user-friendly read, but the most basic instruction is to press the space bar (space) go out into the next display, press b button will be back (back) a display, but also the functions of the search string (with vi like), use the instructions in the file, press h.
Parameters:-num the number of rows displayed at one time
-D prompt the user, the screen shown below [Press space to continue, q to quit.], If the user pressed the wrong button, it will show [Press h for instructions.] Rather than the beep
Cancellation of a special character meet-l ^ L (feed characters) will be suspended during the function
-F When calculating the number of rows to the number of rows in fact, rather than wrap the line after the number of (some single words too long will be extended by two or more lines)
-P not to scroll way to show each page, but first clear the screen and then display
-P-c with similar difference is that the first display and then clear the other old data
-S to have their two lines or more consecutive blank line, the substitution is a line of blank lines
-U does not appear under the quotation marks (according to the specified terminal environment variable TERM vary)
+ / Displayed before each file in the search for the string (pattern), and then started to show after the string
+ Num num lines from the beginning to show
fileNames to display the contents of the file, can be an example for the complex number:
more-s testfile testfile page by page shows the contents of the file, if more than two consecutive line blank line blank line Zeyi line display.
more +20 testfile line from 20th starting to show the contents of the file testfile.

Name: mv

Permissions: All users


mv [options] source dest
mv [options] source ... directory
Description: a file to another file, or several files to another directory.
Parameters:-i, if the destination file already exists, then overwrite the old files first asked whether.


Renamed the file aaa bbb:
mv aaa bbb

All of the C language program moved to a subdirectory Finished:
mv-i *. c

Name: rm

Permissions: All users

Usage: rm [options] name ...

Description: Delete files and directories.

The total 

-I delete one by one asked to confirm before.
-F even if the original file attributes set to read-only, also directly removed, one by one without confirmation.
-R file directory and below are removed one by one.
Delete all C language program files; delete one by one asked to confirm before:
rm-i *. c

Finished directory and subdirectories will be all the files to delete:
rm-r Finished

Name: rmdir

Permission: in the current directory has the appropriate permissions for all users

Usage: rmdir [-p] dirName

Description: Delete empty directory.

Parameters:-p is when the directory is deleted, it has become an empty directory, then the way be removed.


The working directory, a subdirectory called AAA to delete:
rmdir AAA

The BBB in the working directory directory, delete the subdirectory named Test. If the Test deleted, BBB catalog into an empty directory, the BBB also be deleted.
rmdir-p BBB / Test

Name: split

Permissions: All users

Usage: split [OPTION] [INPUT [PREFIX]]


Split a file into several. INPUT separated from the output into a fixed-size file and the file name order of PREFIXaa, PREFIXab ...; PREFIX default is `x. If there is no INPUT file or `-, read from standard input into the data.

Marina pocket 

-B, - bytes = SIZE

SIZE value of each output file size, units of byte.
-C, - line-bytes = SIZE

Each output file, the largest single byte number.
-L, - lines = NUMBER

NUMBER value is the number of columns for each output file size.

The same with the-l NUMBER.
- Verbose

Each output file is opened in the former, print out debugging information to standard error output.
- Help

Display supplementary information and then leave.
- Version

Display version information and exit.
SIZE can be added to unit: b on behalf of 512, k on behalf of 1K, m behalf of 1 Meg.


PostgresSQL large database backup and restore:

Postgres allows tables larger than that due to your system files of the maximum capacity, so to form a single dump file may be a problem, use split to split the file.

% Pg_dump dbname | split-b 1m - filename.dump.


% Createdb dbname
% Cat filename.dump .* | pgsql dbname

Name: touch

Permissions: All users

touch [-acfm]
[-R reference-file] [- file = reference-file]
[-T MMDDhhmm [[CC] YY] [. Ss]]
[-D time] [- date = time] [- time = (atime, access, use, mtime, modify)]
[- No-create] [- help] [- version]
file1 [file2 ...]

touch command to change file time records. ls-l to display the files time record.

a change in the time to read the file record.
m to change the file modification time record.
c If the purpose of the file does not exist, will not create a new file. And - no-create the same effect.
f not used to with other unix systems retain compatibility.
r using the reference file record the time, and - file the same effect.
d set the time and date, you can use a variety of formats.
t set the time record files, the format command with the same date.
- No-create do not create new files.
- Help lists the instruction format.
- Version Display version information.


The most simple usage, when the file records to the present time. If the file does not exist, the system will create a new file.

touch file
touch file1 file2

Time to file record will be at 6:03 p.m. on the on May 6, the year two thousand. Time format can refer to the date command, at least enter MMDDHHmm, is the day of hours and minutes.

touch-c-t 05061803 file
touch-c-t 050618032000 file

Time to file and referencefile change to the same record.

touch-r referencefile file

Time to file record into at 6:03 p.m. on the on May 6, the year two thousand. Time can use am, pm or 24 hour format, date, you can use other formats such as 6 May 2000.

touch-d "6:03 pm" file
touch-d "05/06/2000" file
touch-d "6:03 pm 05/06/2000" file

Name: at

Permissions: All users

Usage: at-V [-q queue] [-f file] [-mldbv] TIME

Note: at TIME allows the user to specify the implementation of a program at this particular time or instructions, TIME format is HH: MM where HH is hours, MM is minutes, you can even specify am, pm, midnight, noon, teatime (that is 16 o'clock Chung) and other spoken word.

If you want to specify more than one day's time, you can use MMDDYY or MM / DD / YY format, where MM is the minute, DD is the first few days, YY is the year. In addition, users can even be used like now + flexible specified time interval to which the time interval can be minutes, hours, days, weeks 

In addition, users can also specify that today or tomorrow to today or tomorrow. When the specified time and after pressing enter, at will to enter chat mode and asked to enter commands or programs, when you enter the finished press ctrl + D to complete all actions for the implementation of the results will be returned to your account in the .

Into account:

-V: print version number
-Q: Use the specified queue (Queue) to store, at the data is stored in the so-called queue, the user can use multiple queue, the queue number for the a, b, c. .. z and A , B, ... Z a total of 52
-M: even if the program / instruction execution is completed there is no output, but also send letters to users
-F file: read pre-written command file. Users do not have to use the interactive mode to enter, can begin to write all files specified after the first one to read
-L: lists all of the specified (users can also use the atq without at-l)
-D: delete the specified (users can also use atrm without at-d)
-V: list has been completed but not yet removed all of the designated

Three days after the 17 o'clock Chung Executive / bin / ls:
at 5pm + 3 days / bin / ls

Three weeks later the 17 o'clock Dr implementation of / bin / ls:
at 5pm + 2 weeks / bin / ls

Implementation of tomorrow's 17:20 / bin / date:
at 17:20 tomorrow / bin / date

1999, the last day of last-minute print the end of world!
at 23:59 12/31/1999 echo the end of world!

Name: cal

Permissions: All users

Usage: cal [-mjy] [month [year]]


Show calendar. If only one parameter, represents the year (1-9999), showed that the calendar year. Year must all write: `` cal 89 will not be displayed calendar 1989. Use two parameters, then the month and year. If no parameters are shown this month's calendar.
3 September 1752 to switch to Western from the date of the new calendar, because this time the majority of countries have adopted the new calendar, with 10 days to be removed, so the calendar month is different. Prior to Old Style.

Marina pocket 

-M: to Monday for the first day of the week is displayed.
-J: in Caesar's calendar shows, that the number of days since January 1 show.
-Y: Show this calendar.


cal: Show this month's calendar.

[Root @ mylinux / root] # date
Tue Aug 15 08:00:18 CST 2000
[Root @ mylinux / root] # cal
August 2000
Su Mo Tu We Th Fr Sa

[Root @ mylinux / root] #

cal 2001: Show Calendar Year 2001.

[Root @ mylinux / root] # cal 2001

January February March
Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa
7 8 9 10 1,112,134,567,891,045,678 9 10
14 15 16 17 18 1,920,111,213,141,516 1,711,121,314,151,617
21 22 23 24 25 2,627,181,920,212,223 2,418,192,021,222,324
28 29 30 31 25 26 27 2,825,262,728,293,031

April May June
Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa
8 9 10 11 12 13 1,467,891,011,123,456,789
15 16 17 18 19 2,021,131,415,161,718 1,910,111,213,141,516
22 23 24 25 26 2,728,202,122,232,425 2,617,181,920,212,223
29 30 27 28 29 30 3,124,252,627,282,930

July August September
Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa
8 9 10 11 12 1,314,567,891,011,234,567 8
15 16 17 1,819,202,112,131,415 1,617,189,101,112,131,415
22 23 24 25 26 2,728,192,021,222,324 2,516,171,819,202,122
2,930,312,627,282,930 3,123,242,526,272,829
October November December
Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa
7 8 9 10 11 1,213,456,789,102,345,678
14 15 16 1,718,192,011,121,314 1,516,179,101,112,131,415
21 22 23 24 25 2,627,181,920,212,223 2,416,171,819,202,122
28 2,930,312,526,272,829 3,023,242,526,272,829
30 31

[Root @ mylinux / root] #

cal 5 2001: Show Calendar Year in May 2001.

[Root @ mylinux / root] # cal 5 2001
May 2001
Su Mo Tu We Th Fr Sa

[Root @ mylinux / root] #

cal-m: to the first day of the week Monday for the way to show this month's calendar.

[Root @ mylinux / root] # cal-m
August 2000
Mo Tu We Th Fr Sa Su
123 456
28 29 30 31

[Root @ mylinux / root] #

cal-jy: to the number of days since January 1st of this year's calendar display.

[Root @ mylinux / root] # cal-jy

January February
Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat
2,345,678,373,839,404,142 43
9,101,112,131,415,444,546 47 48 49 50
16 17 18 19 20 21 2,251,525,354,555,657
23 24 2,526,272,829,585,960
30 31
March April
Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat
65 66 67 68 69 70 7,193,949,596,979,899
72 737,475,767,778,100 101 102,103,104,105,106
79 808,182,838,485,107 108 109,110,111,112,113
868,788,899,091,114 116,117,118,119,120 115
May June
Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat
122 123 124 125 126,127,153,154,155
128 129 130 131 132,133,134,156,157 158,159,160,161,162
135 136 137 138 139,140,141,163,164 165,166,167,168,169
142 143 144 145 146,147,148,170,171 172,173,174,175,176
149,150,151,152,177 178,179,180,181,182

July August
Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat
183 214,215,216,217,218
184 185 186 187 188,189,190,219,220 221,222,223,224,225
191 192 193 194 195,196,197,226,227 228,229,230,231,232
198 199 200 201 202,203,204,233,234 235,236,237,238,239
205 206 207,208,209,210,211 240,241,242,243,244
212 213
September October
Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat
245 246 275 276 277,278,279,280,281
247 248 249 250 251,252,253,282,283 284,285,286,287,288
254 255 256 257 258,259,260,289,290 291,292,293,294,295
261 262 263 264 265,266,267,296,297 298,299,300,301,302
268,269,270,271,272 273,274,303,304,305

November December
Sun Mon Tue Wed Thu Fri Sat Sun Mon Tue Wed Thu Fri Sat
306 307,308,309,336,337
310 311 312 313 314,315,316,338,339 340,341,342,343,344
317 318 319 320 321,322,323,345,346 347,348,349,350,351
324 325 326 327 328,329,330,352,353 354,355,356,357,358
331 332 333,334,335,359,360 361,362,363,364,365

[Root @ mylinux / root] #

Name: crontab

Permissions: All users

crontab [-u user] filecrontab [-u user] (-l |-r |-e)
crontab is used to allow users at a fixed time or at regular intervals used to run the program, in other words, that is similar to the user's time-table. -U user is to set the specified user's schedule, this premise is that you must have the authority (such as a root) can specify the time-table to others. If you do not use the-u user, then, is that when setting your own schedule.


-E: the implementation of a text editor to set the schedule, pre-determined text editor is VI, if you want to use another text editor, then please set the VISUAL environment variable to specify that a text editor (for example setenv VISUAL joe)
-R: Remove the current time-table
-L: lists the current time-table

Time-table format is as follows:
f1 f2 f3 f4 f5 program

Where f1 is said minutes, f2 the hour, f3, said a few days of the month, f4 that month, f5, said the first few days in a week. program indicated that the implementation of the program.
When f1 is * per minute, said the implementation of program, f2, said every hour for the * implementation of the program, the other analogy that when f1 is ab from a minute to b minutes this time to perform, f2 is ab said, from a to b hours to be implemented, the rest of analogy when f1 is * / n that the n-minute time intervals for each run once, f2 for the * / n, said n-hour time intervals for each run once, the rest by analogy When f1 is a, b, c, ... that the first a, b, c, ... minutes to perform, f2 for the a, b, c, ... that the first a, b, c. .. hours to perform, the rest by analogy

Users can also store all the settings first in the file file in the way with crontab file to set time table.

The first monthly 0 minutes every hour to perform a / bin / ls:
0 7 * * * / bin / ls

In December, the daily 6 am to 12 points, every 20 minutes to perform a / usr / bin / backup:
0 6-12/3 * 12 * / usr / bin / backup

Monday to Friday 5:00 pm each day send a letter to the [email protected]:
0 17 * * 1-5 mail-s "hi" [email protected] </ tmp / maildata

Midnight monthly daily 0:20, 2:20, 4:20 .... implementation of the echo "haha"
20 0-23/2 * * * echo "haha"


When the program at the time you specify the implementation, the system will send a letter to you, display the contents of the implementation of the program, if you do not wish to receive such a letter, please leave a space on each line to add> / dev / null 2> & 1 can.

Name: date

Permissions: All users


date [-u] [-d datestr] [-s datestr] [- utc] [- universal] [- date = datestr] [- set = datestr] [- help] [- version] [ + FORMAT] [MMDDhhmm [[CC] YY] [. ss]]


date can be used to display or set the system date and time, in the display, the user can set the format to display format set to a plus sign followed by a number of markers, which can be used to mark the list as follows:


%: Print%
% N: the next line
% T: tabbing
% H: hour (00 .. 23)
% I: Hour (01 .. 12)
% K: hours (0 .. 23)
% L: hour (1 .. 12)
% M: minute (00 .. 59)
% P: Display the local AM or PM
% R: direct indication of the time (12 hour format as hh: mm: ss [AP] M)
% S: from January 1, 1970 00:00:00 UTC seconds so far
% S: second (00 .. 61)
% T: direct display time (24 hour)
% X: equivalent to% H:% M:% S
% Z: Time Zone Display

% A: day of the week (Sun.. Sat)
% A: day of the week (Sunday.. Saturday)
% B: month (Jan.. Dec)
% B: month (January.. December)
% C: direct indication of the date and time
% D: Day (01 .. 31)
% D: direct indication of the date (mm / dd / yy)
% H: with the% b
% J: the first days of the year (001 .. 366)
% M: month (01 .. 12)
% U: the first few weeks of the year (00 .. 53) (with Sunday as the case of the first day of the week)
% W: the first days of the week (0 .. 6)
% W: The first weeks of the year (00 .. 53) (with Monday as the case of the first day of the week)
% X: direct indication of the date (mm / dd / yy)
% Y: the last two digits of the year (00.99)
% Y: a full year (0000 .. 9999)

Plus, as if not to start, then to set the time, and time format MMDDhhmm [[CC] YY] [. Ss], where MM is the month, DD for the day, hh is hour, mm is minutes, CC for the first two digits of the year, YY is the year after the two figures, ss is seconds into account:

-D datestr: Show datestr in the set time (non-system time)
- Help: display auxiliary information
-S datestr: Set the system time in the set time datestr
-U: display the current GMT
- Version: Display version number

Display time of jump, and then display the current date:
date +% T% n% D

Show the month and the number of days:
date +% B% d

Show date and set the time (12:34:56):
date - date 12:34:56


When you do not want meaningless 0 (eg 1999/03/07), you can insert the tag - symbols, such as date +%-H:%-M:%-S will no time in minutes and seconds significance of 0 to remove, such as changes to the original 08:09:04 8:9:4. In addition, only those who obtained permission (such as root) to set the system time.

When you change the system to root identity time, please remember to clock-w to write the CMOS system time, so the next reboot, the system will continue to hold the latest time the correct value.

Name: sleep

Permissions: All users

Usage: sleep [- help] [- version] number [smhd]

Description: sleep can be used to delay action for some time now


- Help: display auxiliary information
- Version: Display version number
number: the length of time, the back can be accessed by s, m, h or d
Where s is seconds, m is minutes, h is hours, d for the number of days

Displays the current time delay 1 minute, then again display the time:
date; sleep 1m; date

Name: time

Permissions: All users

Usage: time [options] COMMAND [arguments]

Note: time-use instructions, is to measure consumption of a specific instruction execution time and required resources information system. Such as CPU time, memory, input and output and so on. Needs special attention is part of the information displayed is not out in Linux. This is because the Linux distribution function on the part of the resources and time directive is not the same way by default, so that instruction time can not obtain such information.

The total 

-O or - output = FILE
The results set the output file. This option will be time to write the output file specified. If the file already exists, the system will overwrite its contents.
-A or - append
Use with-o, the result will be written to the end of the file, not overwrite the original content.
-F FORMAT or - format = FORMAT
FORMAT string to set the display. When this option is not set when

  • Sign in spring struts2.0 hibernate user authentication 2009-02-27

    Engage in a day has finally put the ghost of a user log in to engage in things out. . Ah first experience with a spring to manage the bean is a good tool. Of course, far more than this spring profound role in it. This is called a simple sense of the

  • Based on JDBC, JPA Annotation achieve simple CRUD Generic Dao 2009-02-27

    The origin of ideas are pretty long history of reasons: [Use iBATIS history] The use of iBATIS has been a long time, the system is to use the CRUD template tool to generate the code, although there are tools to generate, but looked at a lot of CRUD t

  • Hibernate.cfg.xml configuration file (including the primary key generation strategy Introduction) 2009-02-27

    Hibernate.cfg.xml configuration file: <? xml version = "1.0" encoding = "utf-8"?> <! DOCTYPE hibernate-configuration PUBLIC "- / / Hibernate / Hibernate Configuration DTD / / EN" "hibernate-configuration-2.0.dtd

  • Hibernate connection pool configuration 2009-02-27

    Hibernate connection pool configuration <! - Jdbc -> <property name="connection.driver_class"> oracle.jdbc.driver.OracleDriver </ property> <property name="connection.url"> jdbc: oracle: thin: @

  • Nan-Jing 5: When IBatis.Hibernate mixed affairs, pay attention to your SQL 2009-02-27

    【Problem】 Now, in the development of the so-called multi-storey JavaEE applications, data persistence layer is always essential, and "Automatic" of ORM - Hibernate, and "all-manual-type" of SqlMap - IBatis, equivalent data are Persiste

  • Process migration from tomcat to websphere changes 2009-02-27

    Process migration from tomcat to websphere changes Because customers use the web application server software used by different what tomcat5, tomcat6, websphere5.1, websphere6.1, weblogic8, and so on, and the software used inconsistent standards, ibm'

  • [Reprint] Java professionals required books and list of sites 2009-02-27

    Concurrent Programming in Java: Design Principles and Patterns (Doug Lea) Concurrent Programming in Java: Design Principles and Patterns, 2nd edition (Doug Lea; Addison-Wesley, 1999 years) Java Concurrent Programming - Design principles and patterns

  • NoClassDefFoundError: javax / servlet / Servlet 2009-02-27

    In the project in order to achieve a listener in web.xml set up a listener, did start in Tomcat actually occurred after java.lang.NoClassDefFoundError: javax / servlet / ServletContextListener this anomaly google and found the reasons for the lack of

  • Hibernate Inteceptor 2009-02-27

    The end of the project stage, the client suddenly put forward a very troublesome but normal demand, the system records all changes must be carried out. Formats such as: 2004.1.1 12:30 Ikuya wind orders Sales Order Date 2004.1.2-> 2004.1.3 The first t

  • Choose Hibernate or iBATIS has its reasons 2009-02-27

    Hibernate features: Hibernate powerful database has nothing to do with good, O / R mapping ability, and if you are very proficient in Hibernate, but also for Hibernate to conduct an appropriate package, then your project will be the entire persistenc

  • Project management experience 2009-02-28

    Say, each project manager has its own different experiences, different experiences. And different projects, different regions, and different stakeholders, policies are not the same. Overall, I would be regarded as its own below a rough summary. I hop

  • Openfire Plugin Developer's Guide 2009-02-28

    Introduction Openfire features plug-ins are enhanced. This document is a guide to developers to create plug-ins. The structure of a plug-in Plug-ins Plug-ins openfireHome stored in the directory. When deploying a plug-in jar or war file, it will auto

  • jBPM Development Getting Started Guide 2009-02-28

    Although the workflow is still immature stage of development, not even a recognized standard. But its application has already been launched in the Express, indicating the market's demand for job-flow framework are urgent and enormous. Backgrounds of

  • Software development sunflower Baodian [reprint] 2009-02-28

    Master the ability to reuse code very familiar with the new API's fast. This is because, he once used a lot of the API, have a lot of reusable code. He knows what is available and what is deficient. He has been using Qt, also used by gtk +, also used

  • Maven 2.0: Compile. Test. Deployment. Run 2009-02-28

    <url> </ url> <dependencies> <dependency> <groupId> junit </ groupId> <artifactId> junit </ artifactId> <version> 3.8.1 </ version> <scope> test </ scope> <

  • web test summary 2009-02-28

    In the Web engineering process, Web-based system testing, recognition and acceptance is an important and challenging job. Web-based system testing with the traditional software testing different, it will not only need to check and verify whether the

  • What is the JPA 2009-02-28

    Same, JDO, also started compatible JPA. At the field of ORM, it seems that JPA is a benevolent government, is the normative specification. At the support of major manufacturers, JPA use became widespread. 2 Spring Spring + Hibernate often referred to

  • lighttpd + fastcgi built a server how to preserve the status of server 2009-02-28

    Requirements: server-side has much static files, there is much use of c + + to prepare the operational components necessary to carry out these functions on the external packaging Published Service, server-side state required to preserve the client (s

  • Hundred software developers interview question 2009-03-01

    Hundred software developers interview question Think employed to engage in software development of smart people is not easy. The event of accidentally, it will get a pile of low-energy large baboons. I met last year on this matter. You certainly do n

  • Depth understanding of the eval function in javascript 2009-03-01 In this paper, the discovery of an appropriate title is not so easy, huh, huh, so in this note under the first two purposes of this article: (1) introduction of the eval function in javascript usage (2) how to