Linux system Management of operation and maintenance notes (I.)

1, Account management:

Account Additions:

Add a user name, set a password (USERADD,PASSWD), add a group (groupadd), join a user to a group (USERMOD-G);

Create a user and specify the home directory (useradd-d)

Add a user to two groups (Usermod-g group1,group2 user) at the same time, and see if a user belongs to a group (groups);

View group, passwd, Shadow, Gshadow use commands: Example: Cat/etc/grouop or Tail-1 (2, 3, 4 ...)/etc/group

or grep newgroup/etc/group

To add users to a group: GPASSWD-A user Group

Remove users from group: gpasswd-d user Group

Deletion of Accounts:

Delete account (Userdel user,userdel-r user), delete (RM-RF user), delete group (Groupdel group), delete (RM-RF group) completely;

Delete Password: passwd-d user

Account permissions:

change user name (usermod-l newuser user or usermod-d/home/newuser newuser,mv/home/user/home/newuser);

Change group name (rename): Groupmod-n newgroup Group

Lock account: Usermod-l user

Unlock: Usermod-u User

Query password status: Passwd-s user

Set User group administrator: GPASSWD-A user name to manage user groups

View Current User Uid:id

View Users: WhoAmI

2, File Management:

New file: Touch file

To view the contents of the file: Cat-n file (outputs the contents of the files from Nth line) or NL file (outputs the contents from the first line and displays the line numbers);

More file (starting from the first line) or less file (better than more); Head-n file (only the first n rows are displayed);

Tail-n file (only the following n rows are displayed)

New Catalog: mkdir directory

Add permissions: chmod 777 file or chmod ugo+rwx file

Delete Files: RM file

Delete files or directories: RM-RF directory

Delete directory: RmDir directory

Find file: Find/-name "file" or Find/-name ' *file* ' (Fuzzy Lookup) or find/-name "file"-ls (find file and display file information)

View current directory: PWD

3, partitioning, formatting:

Partitioning with fdisk (fdisk-l;fdisk/dev/sd*)

Formatted partition: With Mkfs.bfs mkfs.ext2 mkfs.jfs mkfs.msdos Mkfs.vfatmkfs.cramfs

Mkfs.ext3 Mkfs.minix mkfs.reiserfs Mkfs.xfs and other commands to format the partition (mkfs.ext3/dev/sda*)

Loading: mkdir/mnt/sda*

mount/dev/sda*/mnt/sda*

Df-lh

Entry: cd/mnt/sda*

View hard disk Capacity: DF

4, display current version information: Uname-r[-a]

Show current process: PS or ps-a (show All Programs) or Ps-aux (-u Show All user programs)

Kill process: Kill-q (or-ls stop process)

Dynamic monitoring display process: Top

View memory Information: free-m

Shutdown: shutdown-h Now

Timed Restart: shutdown-r +30 (restart after 30 minutes)

This article from "Operations Notes" blog, declined reprint!

Linux system Management of operation and maintenance notes (I.)