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This article mainly shows you the "sample analysis of quota in CentOS", which is easy to understand and clear. I hope it can help you solve your doubts. Let the editor lead you to study and study the "sample analysis of quota in CentOS".

1 theoretical basis

1.1 the concept of Quota

Quota means quota, which is used to limit the amount of space used by users, groups, and folders.

1.2 example of use

-the web server controls the amount of free space available to the site

-mail server controls the amount of free space for users

-file server controls the amount of free space for users

1.3 restricted mode

-controls the amount of free space for each user based on the UID

-controls the amount of free space for each group according to the GID

-controls the amount of free space for each directory according to the directory (directory,project) (xfs available project mode)

1.4 conditions of use

-the EXT format can only restrict the file system, and xfs can restrict project.

-the kernel needs to pre-enable support for Quota

-Quota restriction is valid only for non-administrators

-only Quota for / home is enabled by default, and SELinux needs to be configured for others.

1.5 Configurable objects with restrictions

-by user (User), group (Group), specific directory (project)

-capacity limit or file count limit (block/inode)

-limit values soft (warning and grace time for exceeding space usage) and hard (depriving users of the right to use if they exceed space usage)

-grace time (grace time), the amount of space used exceeds the soft limit and does not reach the processing time limit given by the hard limit (beyond the time limit the soft value becomes the hardest value)

2 actual operation

2.1 preparation before configuration

2.1.1 establish a user group

Groupadd gp1

2.1.2 add group members

Useradd-g gp1 user1

Echo "pwd1" | passwd-- stdin user1

Useradd-g gp1 user2

Echo "pwd1" | passwd-- stdin user2

2.1.2 create user directories and change all groups

Mkdir / home/gp1

Chgrp gp1 / home/gp1

Chmod 2770 / home/gp1

2.1.2 check the file system type

Df-hT / home

The display is as follows:

Filesystem Type Size Used Avail Use% Mounted on

/ dev/mapper/centos-home xfs 5.0G 67M 5.0G 2% / home

2.2 enable the quota feature of the file system

2.2.1 Editing fstab

Vim / etc/fstab

The modifications are as follows:

/ dev/mapper/centos-home / home xfs defaults,usrquota,grpquota 0 0

Note, the types are as follows:

-based on user (uquota/usrquota/quota)

-by group (gquota/grpquota)

-according to directory (pquota/prjquota) (cannot be set at the same time as grpquota)

2.2.2 Uninstall and remount

Umount / home

Mount-a

2.2.3 check

Mount | grep home

The display is as follows:

/ dev/mapper/centos-home on / home type xfs (rw,relatime,seclabel,attr2,inode64,usrquota,grpquota)

2.3 check Quota information

2.3.1 Command format

Xfs_quota-x-c "subcommand" [mount point]

Options:

-x: expert mode, use-x to use-c

-c: subcommand option

Subcommand:

Print: list current system parameters, etc.

Df: similar to df, options include-b (block)-I (inode)-h (plus units), etc.

Report: lists quota projects, including-ugr (user/group/project) and-bi, etc.

State: lists the currently supported quota file system information and related startup items

2.3.2 query partitions that support Quota

Xfs_quota-x-c "print"

2.3.3 query the usage of Quota directory

Xfs_quota-x-c "df-h" / hom

2.3.4 display the limit information of the user's Quota

Xfs_quota-x-c "report-ubih" / home

Note: show item plus parameter "- u"

2.4 configuration restrictions

2.4.1 Command format:

Xfs_quota-x-c "limit [- ug] b [soft | hard] = Ni [soft | hard] = N name"

Xfs_quota-x-c "timer [- ug] [- bir] Ndays"

Options:

Limit: restricted objects, including user/group/project

Bsoft/bhard: soft/hard limit of block

Isoft/ihard: soft/hard limit of inode

Name: names of users and groups

Timer: grace time (grace time)

2.4.2 based on user and block size limit

Xfs_quota-x-c "limit-u bsoft=250M bhard=300M user1" / home

Xfs_quota-x-c "limit-u bsoft=250M bhard=300M user2" / home

Check the configuration:

Xfs_quota-x-c "report-ubih" / home

2.4.3 limits based on group and block size

Xfs_quota-x-c "limit-g bsoft=950M bhard=1G gp1" / home

Check the configuration:

Xfs_quota-x-c "report-gbih" / home

2.4.5 configure grace time

Xfs_quota-x-c "timer-ug-b 14days" / home

Verify the configuration:

Xfs_quota-x-c "state" / home

2.4.6 verify Quta

Su-user1

Dd if=/dev/zero of=123.img bs=1M count=310

Ll-h

Exit

Xfs_quota-x-c "report-ubh" / home

2.5 according to project restrictions

2.5.1 modify fstab

Vim / etc/fstab

2.5.2 Unmount and remount

Umount / home

Mount-a

2.5.3 check cancellation

Xfs_quota-x-c "state"

2.5.4 create a project storage location

Mkdir / home/proj01

2.5.5 specify the project identification number

Echo "01:/home/proj01" > > / etc/projects

2.5.6 specify the project name and associate the project identification number

Echo "proj01:01" > > / etc/projid

2.5.7 initialize the project name

Xfs_quota-x-c "project-s proj01"

Check the configuration:

Xfs_quota-x-c "print" / home

Xfs_quota-x-c "report-pbih" / home

2.5.8 configure limits based on block size

Xfs_quota-x-c "limit-p bsoft=450M bhard=500M proj01" / home

Check the configuration:

Xfs_quota-x-c "report-pbih" / home

2.5.9 verify the configuration

Dd if=/dev/zero of=/home/myquota/123.img bs=1M count=510

2.6Management of Quota

2.6.1 temporarily disable Quota restrictions

Xfs_quota-x-c "disable-up" / home

Check disabled:

Xfs_quota-x-c "state" / home

Authentication is disabled:

Dd if=/dev/zero of=/home/user1/123.img bs=1M count=520

Check the Quota status:

Xfs_quota-x-c "report-pbh" / home

Clean up the test files:

Rm-rf / home/user1/123.img

2.6.2 temporary launch Quota restrictions

Xfs_quota-x-c "enable-up" / home

Verify startup:

Dd if=/dev/zero of=/home/user1/123.img bs=1M count=520

2.6.3 completely close the Quota restriction

Xfs_quota-x-c "off-up" / home

Test off:

Xfs_quota-x-c "enable-up" / home

Restore shutdown:

Umount / home; mount-a

2.6.4 remove Quota restriction (unrecoverable)

Xfs_quota-x-c "off-up" / home

Xfs_quota-x-c "remove-p" / home

Verify deletion:

Xfs_quota-x-c "report-phb" / home

2.7 using soft connection to implement Quota

1) enable the Quota function of / home partition

Edit fstab

Vim / etc/fstab

The modifications are as follows:

/ dev/mapper/centos-home / home xfs defaults,usrquota,grpquota 0 0

2) create a soft connection to the Quota partition

Ln-s / home/mail / var/spool/mail

The above is all the content of the article "sample Analysis of quota in CentOS". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!

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