centos 7 下的xfs文件的备份与恢复
请读者跳过此段，此段为小博主整理的内容，没有详细讲解：
备份：xfsdump -f /opt/dump-dir /media/cdrom
不是（/media/cdrom/）
脚本备份：xfsdump -f /opt/dump-dir /media/cdrom -L dump-sh-dir -M sh-dir
部分目录、文件备份：xfsdump -f /opt/dump--sh-wenjian -s wenjian /media/cdrom -L dump-sh-wenjian -M sh-wenjian
增量备份：
xfsdump -l 1 -f /opt/dump--sh-dir1 /media/cdrom -L dump-sh-dir1 -M sh-dir1
xfsdump -l 2 -f /opt/dump--sh-dir2 /media/cdrom -L dump-sh-dir2 -M sh-dir2
恢复：xfsrestore -f /opt/dump-dir 需要恢复到那个文件夹
xfsrestore -f /opt/dump-dir ./
正文：
为了简化整个过程，小博主这里选择增加一块新的分区，并只给予其1个G的空间大小：
备份
xfsdump -f 备份文件 需要备份的文件
xfsdump -f /opt/dump /media/cdrom
错误示范：xfsdump -f /opt/dump /media/cdrom/ （是.../cdrom 不是.../cdrom/）
在新增加的磁盘上划分1个G，并挂载至/media/cdrom下面
挂载情况如下：
[root@localhost ~]# df -hT
文件系统 类型 容量 已用 可用 已用% 挂载点
......
/dev/sdb1 xfs 1014M 33M 982M 4% /media/cdrom创建一个文件夹和一个多个子文件
[root@localhost cdrom]# pwd
/media/cdrom
[root@localhost cdrom]# ls
[root@localhost cdrom]# mkdir wenjian
[root@localhost cdrom]# vim 1.txt
[root@localhost cdrom]# vim 2.txt
[root@localhost cdrom]# cd wenjian/
[root@localhost wenjian]# vim 1
[root@localhost wenjian]# vim 2
[root@localhost wenjian]# cd ..
[root@localhost cdrom]# find .
.
./wenjian
./wenjian/1
./wenjian/2
./1.txt
./2.txt
使用xfsdump备份命令，所以的内容备份至/opt/dump-dir下
[root@localhost cdrom]# xfsdump -f /opt/dump-dir /media/cdrom
xfsdump: using file dump (drive_simple) strategy
xfsdump: version 3.1.4 (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-dir #输入标签
session label entered: "dump-dir"
--------------------------------- end dialog ---------------------------------
xfsdump: level 0 dump of localhost.localdomain:/media/cdrom
xfsdump: dump date: Fri Sep 14 16:03:17 2018
xfsdump: session id: 73baa490-32c2-4ee3-afcf-e8ae7fc556b7
xfsdump: session label: "dump-dir"
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: 22400 bytes
============================= media label dialog =============================
please enter label for media in drive 0 (timeout in 300 sec)
-> dir #注释
media label entered: "dir"
--------------------------------- 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 24256 bytes
xfsdump: dump size (non-dir files) : 0 bytes
xfsdump: dump complete: 15 seconds elapsed
xfsdump: Dump Summary:
xfsdump: stream 0 /opt/dump-dir OK (success)
xfsdump: Dump Status: SUCCESS
[root@localhost cdrom]# ls /opt/
dump-dir rh
备份成功！
但是，我们平常使用备份命令的时候，都是使用脚本定时备份，那么中间输入标签和注释就会导致备份需要人为跟进，这并不是我们需要的，所以，我们需要在备份的过程中，让其跳过输入的过程：
使用以下命令：（主要是-L和-M）
[root@localhost cdrom]# xfsdump -f /opt/dump--sh-dir /media/cdrom -L dump-sh-dir -M sh-dir
xfsdump: using file dump (drive_simple) strategy
xfsdump: version 3.1.4 (dump format 3.0) - type ^C for status and control
xfsdump: WARNING: most recent level 0 dump was interrupted, but not resuming that dump since resume (-R) option not specified
xfsdump: level 0 dump of localhost.localdomain:/media/cdrom
xfsdump: dump date: Fri Sep 14 16:21:11 2018
xfsdump: session id: c1292efc-b783-41c5-ae3b-f1df342f34ff
xfsdump: session label: "dump-sh-dir"
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: 22400 bytes
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 24256 bytes
xfsdump: dump size (non-dir files) : 0 bytes
xfsdump: dump complete: 0 seconds elapsed
xfsdump: Dump Summary:
xfsdump: stream 0 /opt/dump--sh-dir OK (success)
xfsdump: Dump Status: SUCCESS
[root@localhost cdrom]# ls /opt/
dump-dir dump--sh-dir rh
当然，有时候我们也许只准备备份一个目录，而不是所有的文件，我们可以用下面命令来执行
[root@localhost cdrom]# ls
1.txt 2.txt wenjian
[root@localhost cdrom]# xfsdump -f /opt/dump--sh-wenjian -s wenjian /media/cdrom -L dump-sh-wenjian -M sh-wenjian
xfsdump: using file dump (drive_simple) strategy
xfsdump: version 3.1.4 (dump format 3.0) - type ^C for status and control
xfsdump: level 0 dump of localhost.localdomain:/media/cdrom
xfsdump: dump date: Fri Sep 14 16:24:05 2018
xfsdump: session id: f997126c-08f0-4d56-baef-f68574626250
xfsdump: session label: "dump-sh-wenjian"
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: 21760 bytes
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 23008 bytes
xfsdump: dump size (non-dir files) : 0 bytes
xfsdump: dump complete: 0 seconds elapsed
xfsdump: Dump Summary:
xfsdump: stream 0 /opt/dump--sh-wenjian OK (success)
xfsdump: Dump Status: SUCCESS
[root@localhost cdrom]# ls /opt/
dump-dir dump--sh-dir dump--sh-wenjian rh
增量备份：
好了，现在问题来了，小博主第一天创建了一个a.txt文本，第二天创建了一个在/media/cdrom/wenjian下创建了a.txt文本，如果/media/cdrom文件很大，按照上面的做法就是备份全部文件，而文件只是增加了一个a.txt，所以我们需要用到增量备份
[root@localhost cdrom]# vim a.txt
[root@localhost cdrom]# find .
.
./wenjian
./wenjian/1
./wenjian/2
./1.txt
./2.txt
./a.txt
[root@localhost cdrom]# xfsdump -l 1 -f /opt/dump--sh-dir1 /media/cdrom -L dump-sh-dir1 -M sh-dir1
xfsdump: using file dump (drive_simple) strategy
xfsdump: version 3.1.4 (dump format 3.0) - type ^C for status and control
xfsdump: level 1 incremental dump of localhost.localdomain:/media/cdrom based on level 0 dump begun Fri Sep 14 16:21:11 2018
xfsdump: dump date: Fri Sep 14 16:30:24 2018
xfsdump: session id: 484fd518-e7a3-4f4f-bd49-ad13570b882f
xfsdump: session label: "dump-sh-dir1"
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: 21440 bytes
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 22408 bytes
xfsdump: dump size (non-dir files) : 0 bytes
xfsdump: dump complete: 0 seconds elapsed
xfsdump: Dump Summary:
xfsdump: stream 0 /opt/dump--sh-dir1 OK (success)
xfsdump: Dump Status: SUCCESS
[root@localhost cdrom]# ls /opt/
dump-dir dump--sh-dir dump--sh-dir1 dump--sh-wenjian rh
dump--sh-dir1是dump-dir的增量备份，级别一级
[root@localhost cdrom]# vim wenjian/a.txt
[root@localhost cdrom]# find .
.
./wenjian
./wenjian/1
./wenjian/2
./wenjian/a.txt
./1.txt
./2.txt
./a.txt
[root@localhost cdrom]# xfsdump -l 2 -f /opt/dump--sh-dir2 /media/cdrom -L dump-sh-dir2 -M sh-dir2
xfsdump: using file dump (drive_simple) strategy
xfsdump: version 3.1.4 (dump format 3.0) - type ^C for status and control
xfsdump: level 2 incremental dump of localhost.localdomain:/media/cdrom based on level 1 dump begun Fri Sep 14 16:30:24 2018
xfsdump: dump date: Fri Sep 14 16:31:53 2018
xfsdump: session id: c3c686c1-8cda-4069-b404-8a9cf2a14612
xfsdump: session label: "dump-sh-dir2"
xfsdump: ino map phase 1: constructing initial dump list
xfsdump: ino map phase 2: pruning unneeded subtrees
xfsdump: ino map phase 3: skipping (only one dump stream)
xfsdump: ino map construction complete
xfsdump: estimated dump size: 21440 bytes
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 22432 bytes
xfsdump: dump size (non-dir files) : 0 bytes
xfsdump: dump complete: 0 seconds elapsed
xfsdump: Dump Summary:
xfsdump: stream 0 /opt/dump--sh-dir2 OK (success)
xfsdump: Dump Status: SUCCESS
[root@localhost cdrom]# ls /opt/
dump-dir dump--sh-dir dump--sh-dir1 dump--sh-dir2 dump--sh-wenjian rh
二级备份dump--sh-dir2
注意：恢复从二级到一级，如果都是一级备份，按最好一次的备份文件恢复即可，当然，首先要恢复完整备份
恢复：
[root@localhost cdrom]# ls
1.txt 2.txt a.txt wenjian
[root@localhost cdrom]# rm -rf *
[root@localhost cdrom]# ls
[root@localhost cdrom]# xfsrestore -f /opt/dump-dir ./
xfsrestore: using file dump (drive_simple) strategy
xfsrestore: version 3.1.4 (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: localhost.localdomain
xfsrestore: mount point: /media/cdrom
xfsrestore: volume: /dev/sdb1
xfsrestore: session time: Fri Sep 14 16:05:04 2018
xfsrestore: level: 0
xfsrestore: session label: "dump-dir"
xfsrestore: media label: "dir"
xfsrestore: file system id: f3be7c4c-1c3b-4522-96f1-219a68c3421b
xfsrestore: session id: b99f416c-d9d6-4b70-b4c8-598ad3250ea5
xfsrestore: media id: 5ed60d57-7a56-458d-847d-54f7b23149a6
xfsrestore: using online session inventory
xfsrestore: searching media for directory dump
xfsrestore: reading directories
xfsrestore: 2 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 /opt/dump-dir OK (success)
xfsrestore: Restore Status: SUCCESS
[root@localhost cdrom]# ls
1.txt 2.txt wenjian
[root@localhost cdrom]# find .
.
./wenjian
./wenjian/1
./wenjian/2
./1.txt
./2.txt
需要注意的是，增量备份只是备份了增加的，所以恢复的时候要先恢复原本的，在恢复增加的！