Linux basic commands

Linux Shutdown and Boot

#shutdown [Options] Time

Option:-C: Cancel the previous shutdown command-H: Shutdown-r: Restart

Time: Now to perform six-point restart at 06:00 a.m.

#shutdown-R &: 6 o'clock in the morning reboot, background execution, press ENTER can continue to do things, if the last not add &, the interface lock, nothing can do

#shutdown-C: Cancel the previous restart command

#shutdown-H Now: Shut down immediately

Other shutdown commands (less secure, data may be lost):

1. #halt

2. #poweroff

3. Init 0

Other Restart commands:

1, reboot

2, Init 6 (not recommended)

System operating level:

0-Power off 1-Single user 2-incomplete user, without NFS service 3-Full multiuser 4-Unassigned 5-graphical interface 6-restart

Query the current operating level of the system: #runlevel

#cat/etc/inittab: Modify the system default run level Id:3:initdefault: (Boot into character interface)

Exit Login Command: Logout

Linux Mount commands

#mount: Querying devices that are already mounted in the system

#mount-A: Automatically mounts based on the contents of the/etc/fstab profile

#mount [-t file system] [-o Special Options] device mount name mount point

Options:

-T File system: Add File system and other types to make mount type, can ext3, Ext4, iso9660 and other file system

-O Special option: You can specify additional options for mounting

Example: #mount-o remount,noexec/home: Using the Noexec

#cd/Home #vi hello.sh (#! /bin/bash echo "Hello") #chmod 755 hello.sh

#./hello.sh Run error prompt does not have permission to re-modify Mount command: #mount-o remount,exec/home

To mount a disc:

#ls/dev Sr0 is the system's own

1, set up mount point: #mkdir/mnt/cdrom (an empty directory, the equivalent of Windows inserted u disk letter)

2. Mount disc: #mount-T iso9660/dev/cdrom/mnt/cdrom/

#mount/dev/sr0/mnt/cdrom/to mount the device/dev/sr0 to the/mnt/cdrom/directory

Uninstall command

#umount device file name or mount point

such as: Exit the/mnt/cdrom directory to uninstall #umount/mnt/cdrom or (/dev/sr0) #pwd查看目录

Mount USB Drive

#fdisk-L View USB drive device file name

#mount-T vfat/dev/sdb1/mnt/usb/

Note: The NTFS file system is not supported by default on Linux (mounting the removable hard disk does not work, you have to recompile the kernel to support NTFS)

Viewing logged-in user information

1. #w

2. #who

3, #last查询当前登录和过去登录的用户信息 (default read/var/log/wtmp file data)

4, #lastlog query the last logon time for all users (default read/var/log/lastlog file data)

Linux basic commands