Use Linux operating system commands to send information __linux

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As Linux develops today, many features can already be done in a visual interface. In many cases, however, commands are useful, especially for Linux system administrators who can communicate with other users by ordering system breaks, bulletin board information, and public information.

Set Login prompt

Purpose of/ETC/MOTD file

/ETC/MOTD (bulletin board information), the contents of the/etc/motd file are displayed at the user's terminal each time the user logs on. System administrators can edit system activity messages in a file, such as when an administrator notifies the user when the system is upgrading the software or hardware, when the system is maintained, and so on. If the shell supports Chinese, you can also use Chinese, which makes it easier to understand. /ETC/MOTD disadvantage is that many users now log into the system automatically choose to enter the graphical interface, so this information is often not seen.

Purpose of/etc/issue file

The main difference between the use of/etc/issue files and/ETC/MOTD files is that when a network user or a serial port is logged on to the system, the/etc/issue file content appears before the login prompt, and/etc/ The MOTD content is displayed after the user successfully logs on to the system.

Using the Write command

Users can use the Write command to send messages to other online users. Format:

QUOTE:
#write username [TTY]

In the shell prompt symbol input write,username refers to the user name that accepts the send message. If a user logs on to the system multiple times, the TTY parameter specifies the terminal to send. The prerequisite for sending information using write is that the user has logged on to the system. Otherwise, the following prompts appear:

QUOTE:
#write CJH

WRITE:CJH is isn't logged in

You can use the WHO command to query the name of the logged-on user. You can then enter the information you want to send. When the input is complete, type EOF to indicate the end of the message and use the CRTL+D key combination to send the message. The input appears on the user's screen while the communication is aborted.

If you can use the Write command on a network to add a host name or domain name after username, establish network traffic. If you want to communicate with the BJ user on the CAO host, use the command:

QUOTE:
#write Bj@cao

You can use the Rusers command to list the logged-in users on all local networks.

Wall command

If you want to send a message to all users in the system, you can use the wall command, Wall says: Write all. Enter wall, and then edit the information if shell support can be used in Chinese. Then use the Crtl+d key combination to send the message. This will receive information on the desktop of all logged-in users of the system. If you are on a network, you can use the Rwall command to send information to all users on the local area network.

Talk command

The talk command enables two-way conversations with another logged-on system user. The system administrator enters the information and the user can enter his or her own information. Both sides can see the screen information when communicating. Format:

QUOTE:
#talk username

An example:

#talk b

The other screen shows:

QUOTE:
Message from Talk_Daemon@www.cao.com at 7:18 ...
Talk:connection requested by b@www.cao.com.
Talk:respond With:talk b@www.cao.com

Then enter the talk screen interface, the information entered by both sides. will appear on each other's screen.

Use Crth+c to disconnect after the user completes the session. As with write, you can use a host name or domain name after username to establish a network session connection.

MESG command

Users can prevent other users from sending messages to interrupt their work, using the MESG n command to prevent other users from sending messages. When someone tries to use write to send him a message, the sender will see the prompt:

QUOTE:
#write: User has messages disabled on pts/n?

But a superuser can send a message to any user, even if the user uses the MESG n command. To resume receiving information entry:

QUOTE:
Mesg-y

Linux server running software is mainly open source software, and are constantly upgraded, stable and beta version of the alternate. If you are a Linux network administrator, you often need to look at the appropriate site, whether there are patches, whether there is a bug fix, whether the need to upgrade. Network administrators also provide security services to users. To the user to send regular security information, is to let users have security awareness. You can help manage users better by using the commands above.