Linux系统学习第四章:文件压缩、打包与备份(二)备份与还原
一、备份:dump
(1)dump -S 设备名 :显示需要备份的设备所在分区所需要的最小的容量
1 [root@localhost php]# dump -S /dev/sda2 2 4710404096
(2)dump -W 查看所有分区是否备份过(或者说在/etc/fstab这个文件中 是否有相应的备份的记录)
1 [root@localhost php]# dump -W 2 Last dump(s) done (Dump '>' file systems): 3 > /dev/sda2 ( /) Last dump: never 4 > /dev/sda3 ( /home) Last dump: never 5 > /dev/sda1 ( /boot) Last dump: never
(3) dump [-uvj] [-level] [-f] 备份后的文件名 要备份的数据
参数说明:
-u 将备份的时间记录到/etc/dumpdates文件中
-v 显示备份进度
-j 使用bzip2进行压缩
-level 用0-9代替这个level代表备份的等级
-f 后面接备份的文件名
1 [root@localhost php]# dump -0uvj -f /root/home_20121205.dump /home 2 DUMP: Date of this level 0 dump: Wed Dec 5 15:51:14 2012 3 DUMP: Dumping /dev/sda3 (/home) to /root/home_20121205.dump 4 DUMP: Excluding inode 8 (journal inode) from dump 5 DUMP: Excluding inode 7 (resize inode) from dump 6 ……(#此处省略备份过程中的相关数据) 7 DUMP: DUMP IS DONE 8 [root@localhost php]# cd /root 9 [root@localhost ~]# ls 10 anaconda-ks.cfg Desktop home_20121205.dump install.log install.log.syslog
我们再来测试一下 dump -W这个命令查看一下:
1 [root@localhost ~]# dump -W 2 Last dump(s) done (Dump '>' file systems): 3 > /dev/sda2 ( /) Last dump: never 4 /dev/sda3 ( /home) Last dump: Level 0, Date Wed Dec 5 15:51:14 2012 5 > /dev/sda1 ( /boot) Last dump: never
因为刚才备份过一次了,所以就有相应的记录了
二、还原:restore
(1)restore -t -f 备份文件
查看备份文件的相关信息
1 [root@localhost ~]# restore -t -f home_20121205.dump 2 Dump tape is compressed. 3 Dump date: Wed Dec 5 15:51:14 2012 4 Dumped from: the epoch 5 Level 0 dump of /home on localhost.localdomain:/dev/sda3 6 Label: /home 7 2 . 8 11 ./lost+found 9 32001 ./admin 10 ……(此处省略其他文件)
(2)restore -C -f 备份文件
查看备份文件与备份所在的目录的现状的差异
1 [root@localhost ~]# restore -C -f home_20121205.dump 2 Dump date: Wed Dec 5 16:04:53 2012 3 Dumped from: the epoch 4 Level 0 dump of /home on localhost.localdomain:/dev/sda3 5 Label: /home 6 filesys = /home
(3)restore -i -f 备份文件
进入互动模式
用help调出所有互动模式下可以使用的命令:
1 [root@localhost ~]# restore -i -f home_20121205.dump 2 restore > help 3 Available commands are: 4 ls [arg] - list directory 5 cd arg - change directory 6 pwd - print current directory 7 add [arg] - add `arg' to list of files to be extracted 8 delete [arg] - delete `arg' from list of files to be extracted 9 extract - extract requested files 10 setmodes - set modes of requested directories 11 quit - immediately exit program 12 what - list dump header information 13 verbose - toggle verbose flag (useful with ``ls'') 14 prompt - toggle the prompt display 15 help or `?' - print this list 16 If no `arg' is supplied, the current directory is used 17 restore > ls 18 .: 19 admin/ dev/ ec_admin/ lost+found/ test/
(4)restore -r -f 备份文件
还原整个文件系统:
1 [root@localhost ~]# restore -r -f home_20121205.dump 2 restore: ./lost+found: File exists 3 restore: ./admin: File exists 4 restore: ./admin/.mozilla: File exists 5 restore: ./admin/.mozilla/extensions: File exists 6 restore: ./admin/.mozilla/plugins: File exists 7 restore: ./admin/.kde: File exists 8 restore: ./admin/.kde/Autostart: File exists 9 ……(省略其他文件)
三、备份文件或磁盘:dd
语法:dd if=被备份的文件 of=备份文件 bs=block块大小 count=block数量
1 [root@localhost ~]# dd if=/etc/passwd of=/home/passwd 2 3+1 records in 3 3+1 records out 4 2028 bytes (2.0 kB) copied, 0.000217227 seconds, 9.3 MB/s 5 [root@localhost ~]# cd /home/ 6 [root@localhost home]# ls 7 360 admin dev ec_admin lost+found passwd test
学习是一个漫长的过程,有时候会迷茫,有时候会孤独,有时候会枯燥,感谢一路上有你