在linux系统中，我们有时会“不小心”误删除一些文件，如果是自己是测试环境服务器可能“无所谓”。但是一旦发生在客户的生产环境，那就是“重大安全事故”。

我们能不能提前对一些重要的文件系统进行备份，以便当我们真的误删除一些重要的文件时，能够及时恢复呢？本次为大家讲解如何使用xfsdump和xfsrestore命令实现RHEL7 xfs文件系统误删除文件的恢复。

1.实验环境

1.VMWare RHEL7.7

命令：

cat /etc/redhat-release

2.实施步骤

1.虚拟机关机

2.新增一块硬盘大小20G

3.虚拟机开机并查看新增磁盘信息

命令：

lsblk |grep "sdb"

4.对新增磁盘进行分区，大小5GB

命令：

echo -e "o\nn\np\n1\n\n+5G\nw" | fdisk /dev/sdb

lsblk |grep "sdb"

5.格式化磁盘分区并挂载

命令：

mkfs.xfs -f /dev/sdb1

mkdir -p /tmp/sdb1

mount /dev/sdb1 /tmp/sdb1

6.创建空文件，空目录，普通文件，普通目录

命令：

cd /tmp/sdb1

mkdir a

mkdir b

touch aa

touch bb

touch kong.txt

echo "aaa" >>aa

echo "bbb" >>bb

mv bb b/

7.使用xfsdump命令备份/dev/sdb1分区中的数据至/root/back目录

前提：如果xfsdump未安装，请安装；yum源可用

yum -install -y xfsdump

命令：

mkdir -p /root/back

xfsdump -f /root/back/dump_sdb1 /dev/sdb1

备注：dump_sdb1为自动定义备份文件名称

[root@rhel77 back]# xfsdump -f /root/back/dump_sdb1 /dev/sdb1
xfsdump: using file dump (drive_simple) strategy
xfsdump: version 3.1.7 (dump format 3.0) - type ^C for status and control
============================= dump label dialog ==============================

please enter label for this dump session (timeout in 300 sec)-> dump_sdb1            #label标签名，可以为空
session label entered: "dump_sdb1"
--------------------------------- end dialog ---------------------------------

xfsdump: level 0 dump of rhel77:/tmp/sdb1
xfsdump: dump date: Sun May 28 19:23:11 2023
xfsdump: session id: b0498d15-755e-4e33-8207-d47830a84bde
xfsdump: session label: "dump_sdb1"
xfsdump: ino map phase 1: constructing initial dump list
xfsdump: ino map phase 2: skipping (no pruning necessary)
xfsdump: ino map phase 3: skipping (only one dump stream)
xfsdump: ino map construction complete
xfsdump: estimated dump size: 30592 bytes
============================= media label dialog =============================

please enter label for media in drive 0 (timeout in 300 sec)-> sdb1
media label entered: "sdb1"    #media标签名，可以为空
--------------------------------- end dialog ---------------------------------

xfsdump: creating dump session media file 0 (media 0, file 0)
xfsdump: dumping ino map
xfsdump: dumping directories
xfsdump: dumping non-directory files
xfsdump: ending media file
xfsdump: media file size 23656 bytes
xfsdump: dump size (non-dir files) : 1088 bytes
xfsdump: dump complete: 12 seconds elapsed
xfsdump: Dump Summary:
xfsdump:   stream 0 /root/back/dump_sdb1 OK (success)
xfsdump: Dump Status: SUCCESS
[root@rhel77 back]# ls         #查看备份后的信息
dump_sdb1
[root@rhel77 back]#

8.模拟删除/tmp/sdb1(/dev/sdb1)下的文件

命令：

cd /tmp/sdb1

rm -rf *

9.执行恢复

命令：

cd /tmp/sdb1

xfsrestore -f /root/back/dump_sdb1 /tmp/sdb1/

tree

备注：dump_sdb1为xfsdump命令备份的文件名称

[root@rhel77 sdb1]# cd /tmp/sdb1
[root@rhel77 sdb1]# xfsrestore -f /root/back/dump_sdb1 /tmp/sdb1/
xfsrestore: using file dump (drive_simple) strategy
xfsrestore: version 3.1.7 (dump format 3.0) - type ^C for status and control
xfsrestore: searching media for dump
xfsrestore: examining media file 0
xfsrestore: dump description: 
xfsrestore: hostname: rhel77
xfsrestore: mount point: /tmp/sdb1
xfsrestore: volume: /dev/sdb1
xfsrestore: session time: Sun May 28 19:23:11 2023
xfsrestore: level: 0
xfsrestore: session label: "dump_sdb1"
xfsrestore: media label: "sdb1"
xfsrestore: file system id: f41c9297-c680-4555-887b-673d47c5693e
xfsrestore: session id: b0498d15-755e-4e33-8207-d47830a84bde
xfsrestore: media id: 0d886f27-6182-408d-89a1-ee0cf1265645
xfsrestore: using online session inventory
xfsrestore: searching media for directory dump
xfsrestore: reading directories
xfsrestore: 3 directories and 5 entries processed
xfsrestore: directory post-processing
xfsrestore: restoring non-directory files
xfsrestore: restore complete: 0 seconds elapsed
xfsrestore: Restore Summary:
xfsrestore:   stream 0 /root/back/dump_sdb1 OK (success)
xfsrestore: Restore Status: SUCCESS
[root@rhel77 sdb1]# ls
a  aa  b  kong.txt
[root@rhel77 sdb1]# tree
.
├── a
├── aa
├── b
│   └── bb
└── kong.txt

2 directories, 3 files
[root@rhel77 sdb1]#

至此，被删除的文件和目录恢复成功！

备注：

1.xfsdump备份和xfsrestore恢复磁盘的前提是磁盘分区始终要处于挂载状态

2.xfsdump -f /root/back/dump_sdb1 /dev/sdb1。

xfsdump -f $destination $source

xfsdump命令备份时，$source只可以使用/dev/sdb1磁盘分区，不可以使用 /tmp/sdb1(/dev/sdb1磁盘分区的挂载点)

3.xfsrestore能够恢复为空的文件和目录

4.xfsrestore -f /root/back/dump_sdb1 /tmp/sdb1

xfsrestore -f $source $destination

xfsrestore命令恢复时，$destination既可以是/tmp/sdb1(/dev/sdb1磁盘分区的挂载点)，也可以是其它目录，但不能直接使用/dev/sdb1磁盘分区名称