linux磁盘管理系列一：磁盘配额管理

磁盘管理系列

linux磁盘管理系列一：磁盘配额管理 http://www.cnblogs.com/zhaojiedi1992/p/zhaojiedi_linux_040_quota.html

linux磁盘管理系列二：软RAID的实现 http://www.cnblogs.com/zhaojiedi1992/p/zhaojiedi_linux_041_raid.html

linux磁盘管理系列三：LVM的使用 http://www.cnblogs.com/zhaojiedi1992/p/zhaojiedi_linux_042_lvm.html

1 前言

在linux系统中，由于是多用户、多任务的环境，如果有少数几个用户大量使用磁盘空间，导致其他用户的正常使用，因此需要对各个用户的磁盘空间进行管理和限定。

2 quota的用途

限制某一个用户的最大磁盘配额

3 quota的使用限制

仅能针对整个文件系统
内核必须支持
只对一般用户生效
这里提供一个样例，针对样例对quota的配置管理做个描述

4 案例讲解

4.1案例描述

创建5个用户user1,user2,user3,user4,user5，密码和用户名相同，初始组为usergrp组。
5个用户都可以取得300M的磁盘使用空间，文件数量不限。超过250M,给于提示。
usergrp这个组内成员最大使用空间1GB。
如果有用户超过soft限制，给14天的宽限时间。

4.2 准备磁盘

[root@mail ~]# fdisk -l      #查看磁盘情况Disk /dev/sda: 42.9 GB, 42949672960 bytes, 83886080 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000bd275Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048     2099199     1048576   83  Linux
/dev/sda2         2099200    83886079    40893440   8e  Linux LVMDisk /dev/sdb: 10.7 GB, 10737418240 bytes, 20971520 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytesDisk /dev/mapper/cl-root: 39.7 GB, 39720058880 bytes, 77578240 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytesDisk /dev/mapper/cl-swap: 2147 MB, 2147483648 bytes, 4194304 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes[root@mail ~]# fdisk /dev/sdb     #对sdb这个盘进行分区，这里就分一个区
Welcome to fdisk (util-linux 2.23.2).Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.Device does not contain a recognized partition table
Building a new DOS disklabel with disk identifier 0xbcd17d69.Command (m for help): n
Partition type:p   primary (0 primary, 0 extended, 4 free)e   extended
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-20971519, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-20971519, default 20971519):
Using default value 20971519
Partition 1 of type Linux and of size 10 GiB is setCommand (m for help): pDisk /dev/sdb: 10.7 GB, 10737418240 bytes, 20971520 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0xbcd17d69Device Boot      Start         End      Blocks   Id  System
/dev/sdb1            2048    20971519    10484736   83  LinuxCommand (m for help): w
The partition table has been altered!Calling ioctl() to re-read partition table.
Syncing disks.
[root@mail ~]# mkfs.ext4 /dev/sdb1
mke2fs 1.42.9 (28-Dec-2013)
Filesystem label=
OS type: Linux
Block size=4096 (log=2)
Fragment size=4096 (log=2)
Stride=0 blocks, Stripe width=0 blocks
655360 inodes, 2621184 blocks
131059 blocks (5.00%) reserved for the super user
First data block=0
Maximum filesystem blocks=2151677952
80 block groups
32768 blocks per group, 32768 fragments per group
8192 inodes per group
Superblock backups stored on blocks: 32768, 98304, 163840, 229376, 294912, 819200, 884736, 1605632Allocating group tables: done
Writing inode tables: done
Creating journal (32768 blocks): done
Writing superblocks and filesystem accounting information: done [root@mail ~]# mkdir /mnt/home          #创建一个目录
[root@mail ~]# mount /dev/sdb1 /mnt/home   #测试挂载下

4.4.创建用户

[root@mail ~]# vim adduserbat.sh #创建一个添加用户的脚本
[root@mail ~]# cat adduserbat.sh #确认下脚本
#!/bin/bashgroupadd usergrp
for user in user1 user2 user3 user4 user5
do useradd -g usergrp -b /mnt/home $userecho $user |passwd --stdin $user
done
[root@mail ~]# sh adduserbat.sh #运行脚本去创建用户
useradd: warning: the home directory already exists.
Not copying any file from skel directory into it.
Creating mailbox file: File exists
Changing password for user user1.
passwd: all authentication tokens updated successfully.
useradd: warning: the home directory already exists.
Not copying any file from skel directory into it.
Creating mailbox file: File exists
Changing password for user user2.
passwd: all authentication tokens updated successfully.
useradd: warning: the home directory already exists.
Not copying any file from skel directory into it.
Creating mailbox file: File exists
Changing password for user user3.
passwd: all authentication tokens updated successfully.
useradd: warning: the home directory already exists.
Not copying any file from skel directory into it.
Creating mailbox file: File exists
Changing password for user user4.
passwd: all authentication tokens updated successfully.
useradd: warning: the home directory already exists.
Not copying any file from skel directory into it.
Creating mailbox file: File exists
Changing password for user user5.
passwd: all authentication tokens updated successfully.
[root@mail ~]# finger user1 #查看用户信息，确保家目录在/dev/sdb1的挂载目录上。
Login: user1 Name:
Directory: /mnt/home/user1 Shell: /bin/bash
Never logged in.
No mail.
No Plan.
[root@mail ~]# id user1 #查看用户信息
uid=2531(user1) gid=2532(usergrp) groups=2532(usergrp)

4.5.检查操作系统支持

前面提到了quota仅仅针对整个文件系统来进行规划的。需要确认我们为各个用户提供存储的位置是独立的文件系统。

[root@mail ~]# df -h /mnt/home      #查看我们的挂载点是否是独立文件系统
Filesystem      Size  Used Avail Use% Mounted on
/dev/sdb1       9.8G   37M  9.2G   1% /mnt/home
[root@mail ~]# mount |grep /mnt/home     #查看我们的文件系统
/dev/sdb1 on /mnt/home type ext4 (rw,relatime,data=ordered)

4.6.让文件系统支持quota设置

[root@mail ~]# mount -o remount,usrquota,grpquota /mnt/home   #重新挂载/mnt/home 支持usrquota,grpquota
[root@mail ~]# mount |grep /mnt/home                           #确认下
/dev/sdb1 on /mnt/home type ext4 (rw,relatime,quota,usrquota,grpquota,data=ordered)
[root@mail ~]# tail -n 1 /etc/mtab >> /etc/fstab         #追加到/etc/fstab中去，确保开机启用quota
[root@mail ~]# cat /etc/fstab                            #确保fstab文件正确性#
# /etc/fstab
# Created by anaconda on Fri Feb 10 03:56:55 2017
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#
/dev/mapper/cl-root     /                       xfs     defaults        0 0
UUID=dd4c6743-bdf5-4899-a43b-814cbe75c618 /boot                   xfs     defaults        0 0
/dev/mapper/cl-swap     swap                    swap    defaults        0 0
/dev/sr0 /mnt/cdrom iso9660 ro,relatime,uid=0,gid=0,iocharset=utf8,mode=0400,dmode=0500 0 0
/dev/sdb1 /mnt/home ext4 rw,relatime,quota,usrquota,grpquota,data=ordered 0 0

4.7.扫描文件系统并新建quota的配置文件

[root@mail ~]# quotacheck -avug
quotacheck: Your kernel probably supports journaled quota but you are not using it. Consider switching to journaled quota to avoid running quotacheck after an unclean shutdown.
quotacheck: Scanning /dev/sdb1 [/mnt/home] done
quotacheck: Cannot stat old user quota file /mnt/home/aquota.user: No such file or directory. Usage will not be subtracted.
quotacheck: Cannot stat old group quota file /mnt/home/aquota.group: No such file or directory. Usage will not be subtracted.
quotacheck: Cannot stat old user quota file /mnt/home/aquota.user: No such file or directory. Usage will not be subtracted.
quotacheck: Cannot stat old group quota file /mnt/home/aquota.group: No such file or directory. Usage will not be subtracted.
quotacheck: Checked 30 directories and 20 files
quotacheck: Old file not found.
quotacheck: Old file not found.

主要参数

-a:　　扫描所有在/etc/mtab内含有quota参数的文件系统
-u:　　针对用户扫描文件与目录的使用情况，会新建一个aquota.user文件
-g:　　针对用户组扫描文件与目录的使用情况，会新增一个aquota.group文件
-v:　　显示扫描过程的信息

4.8 启用quota

[root@mail ~]# quotaon  -avug    #启用quota
/dev/sdb1 [/mnt/home]: group quotas turned on
/dev/sdb1 [/mnt/home]: user quotas turned on

这个命令（quotaon）几乎只需要在第一次启动quota时才需要进行，因为下次等你重新启动时，系统的/etc/rc.d/rc.sysinit这个初始化脚本就会自动执行这个命令。

如果想关闭可以使用quotaoff -avug

4.9.编辑账户的的限值

[root@mail ~]# edquota -u user1

会打开一个vi编辑器，修改我们的设置如下图。

软限制：这个值超过了基本上没事，还是可以创建文件继续使用文件，但是在指定grace天过后就不能在创建文件了。
硬限值：这个值不能超过。

执行如下命令将user1的设置应用到其他用户上

[root@mail ~]# edquota -p user1 -u user2    #-p 指定参考用户，这句话的意思就是将user1的quota信息赋值给user2
[root@mail ~]# edquota -p user1 -u user3
[root@mail ~]# edquota -p user1 -u user4
[root@mail ~]# edquota -p user1 -u user5

4.10.编辑组的设置

[root@mail ~]# edquota -g usergrp

4.11.修改宽限时间

[root@mail ~]# edquota -t

4.12.对用户和组合quota限制查看

[root@mail ~]# quota -uvs user1       #查看user1的限制信息
Disk quotas for user user1 (uid 2531): Filesystem   space   quota   limit   grace   files   quota   limit   grace/dev/sdb1     28K    245M    293M               7       0       0
[root@mail ~]# quota -gvs usergrp
Disk quotas for group usergrp (gid 2532): #查看usergrp的限制信息Filesystem   space   quota   limit   grace   files   quota   limit   grace/dev/sdb1      0K    879M    977M               0       0       0

参数说明

-u:　　指定用户
-g:　　指定用户组
-s:　　以1024为倍数来指定单位，显示M之类的单位
-v:　　显示用户在文件系统的quota值

4.13对文件系统quota限制查看

[root@mail ~]# repquota -as
*** Report for user quotas on device /dev/sdb1                   #这里看到是针对/dev/sdb1的文件系统的
Block grace time: 14days; Inode grace time: 7daysSpace limits                File limits
User            used    soft    hard  grace    used  soft  hard  grace
----------------------------------------------------------------------
root      --     20K      0K      0K              2     0     0
zhao      --     52K      0K      0K             13     0     0
user1     --     28K    245M    293M              7     0     0
user2     --     28K    245M    293M              7     0     0
user3     --     28K    245M    293M              7     0     0
user4     --     28K    245M    293M              7     0     0
user5     --     28K    245M    293M              7     0     0

4.14.quota测试

[user1@mail ~]$ dd if=/dev/zero of=bigfile bs=1M count=270  #先创建一个270M的文件看看
sdb1: warning, user block quota exceeded.                   #这里提示警告了。 也就是我们超过了软限制的值250了。
270+0 records in
270+0 records out
283115520 bytes (283 MB) copied, 0.715086 s, 396 MB/s
[user1@mail ~]$ dd if=/dev/zero of=bigfile2 bs=1M count=40  #这里我们创建一个40M的文件
sdb1: write failed, user block limit reached.               #提示错误了。超出限制了。
dd: error writing ‘bigfile2’: Disk quota exceeded
23+0 records in
22+0 records out
24035328 bytes (24 MB) copied, 0.1165 s, 206 MB/s
[user1@mail ~]$ du -sk                                      #查看两个文件占用情况
300000    .

4.12脚本设置quota信息

上面我们对用户和组的设置，它会启动一个vi编辑器，修改保存才生效。需要交互。如果我们想使用script方式快速设置，那就需要使用setquota命令了。

命令使用 setquota [ -u | -g ] 用户名或者组名块大小软限制块大小硬限制文件数量软限制文件数量大小硬限制文件系统

[root@mail ~]# quota -usv user1     #查看user1的quota信息
Disk quotas for user user1 (uid 2531): Filesystem   space   quota   limit   grace   files   quota   limit   grace/dev/sdb1    293M*   245M    293M  13days      14       0       0
[root@mail ~]# setquota -u user1 400000 500000 100 200 /dev/sdb1    #使用setquota修改
[root@mail ~]# quota -usv user1                                     #再次查看quota信息
Disk quotas for user user1 (uid 2531): Filesystem   space   quota   limit   grace   files   quota   limit   grace/dev/sdb1    293M    391M    489M              14     100     200