完整备份练习

用tar备份系统实例练习
1. 先处理要放置备份资料的目录与权限：
[root@localhost ~]# mkdir /backups
[root@localhost ~]# chmod 700 /backups
[root@localhost ~]# ll -d /backups
drwx------ 2 root root 4096 11-05 16:48 /backups
[root@localhost ~]#

2.建立备份文件backup-system-20081130.tar.bz2
[root@localhost ~]# tar -jcv -f /backups/backup-system-20141105.tar.bz2 > --exclude=/root/*.bz2 --exclude=/root/*.gz --exclude=/home/loop* > /etc /home /var/spool/mail /var/spool/cron /root
[root@localhost ~]# ll -h /backups/
总计 4.0K
-rw-r--r-- 1 root root 46 11-05 16:50 backup-system-20081130.tar.bz2


完整备份工具：dump
备份最小文件系统
[root@localhost ~]# df -h
文件系统              容量  已用 可用 已用% 挂载点
/dev/sda2             9.5G  1.1G  8.0G  12% /
/dev/sda5             8.9G  149M  8.3G   2% /home
/dev/sda1              99M   12M   83M  13% /boot
tmpfs                 506M     0  506M   0% /dev/shm
先测试一下，如果要备份此档案系统，需多少容量？
[root@localhost ~]# dump -S /dev/sda1
6048768
开始完整备份
[root@localhost ~]# dump -0u -f /root/boot.dump /boot
  DUMP: Date of this level 0 dump: Wed Nov  5 16:57:41 2014
  DUMP: Dumping /dev/sda1 (/boot) to /root/boot.dump
  DUMP: Label: /boot
  DUMP: Writing 10 Kilobyte records
  DUMP: mapping (Pass I) [regular files]
  DUMP: mapping (Pass II) [directories]
  DUMP: estimated 5907 blocks.
  DUMP: Volume 1 started with block 1 at: Wed Nov  5 16:57:41 2014
  DUMP: dumping (Pass III) [directories]
  DUMP: dumping (Pass IV) [regular files]
  DUMP: Closing /root/boot.dump
  DUMP: Volume 1 completed at: Wed Nov  5 16:57:41 2014
  DUMP: Volume 1 5960 blocks (5.82MB)
  DUMP: 5960 blocks (5.82MB) on 1 volume(s)
  DUMP: finished in less than a second
  DUMP: Date of this level 0 dump: Wed Nov  5 16:57:41 2014
  DUMP: Date this dump completed:  Wed Nov  5 16:57:41 2014
  DUMP: Average transfer rate: 0 kB/s
  DUMP: DUMP IS DONE

[root@localhost ~]# ll /root/boot.dump /etc/dumpdates
-rw-rw-r-- 1 root disk      43 11-05 16:57 /etc/dumpdates
-rw-r--r-- 1 root root 6103040 11-05 16:57 /root/boot.dump
[root@localhost ~]# cat /etc/dumpdates
/dev/sda1 0 Wed Nov  5 16:57:41 2014 +0800
[root@localhost ~]# dump -W
Last dump(s) done (Dump ‘>‘ file systems):
> /dev/sda2     (     /) Last dump: never
> /dev/sda5     ( /home) Last dump: never
  /dev/sda1     ( /boot) Last dump: Level 0, Date Wed Nov  5 16:57:41 2014
建立level 1的备份
[root@localhost ~]# dd if=/dev/zero of=/boot/testing.img bs=1M count=10
10+0 records in
10+0 records out
10485760 bytes (10 MB) copied, 0.34765 seconds, 30.2 MB/s
[root@localhost ~]# dump -1u -f /root/boot.dump.1 /boot
  DUMP: Date of this level 1 dump: Wed Nov  5 17:00:53 2014
  DUMP: Date of last level 0 dump: Wed Nov  5 16:57:41 2014
  DUMP: Dumping /dev/sda1 (/boot) to /root/boot.dump.1
  DUMP: Label: /boot
  DUMP: Writing 10 Kilobyte records
  DUMP: mapping (Pass I) [regular files]
  DUMP: mapping (Pass II) [directories]
  DUMP: estimated 10283 blocks.
  DUMP: Volume 1 started with block 1 at: Wed Nov  5 17:00:53 2014
  DUMP: dumping (Pass III) [directories]
  DUMP: dumping (Pass IV) [regular files]
  DUMP: Closing /root/boot.dump.1
  DUMP: Volume 1 completed at: Wed Nov  5 17:00:54 2014
  DUMP: Volume 1 10300 blocks (10.06MB)
  DUMP: Volume 1 took 0:00:01
  DUMP: Volume 1 transfer rate: 10300 kB/s
  DUMP: 10300 blocks (10.06MB) on 1 volume(s)
  DUMP: finished in 1 seconds, throughput 10300 kBytes/sec
  DUMP: Date of this level 1 dump: Wed Nov  5 17:00:53 2014
  DUMP: Date this dump completed:  Wed Nov  5 17:00:54 2014
  DUMP: Average transfer rate: 10300 kB/s
  DUMP: DUMP IS DONE
[root@localhost ~]# ll /root/boot*
-rw-r--r-- 1 root root  6103040 11-05 16:57 /root/boot.dump
-rw-r--r-- 1 root root 10547200 11-05 17:00 /root/boot.dump.1
[root@localhost ~]# dump -W
Last dump(s) done (Dump ‘>‘ file systems):
> /dev/sda2     (     /) Last dump: never
> /dev/sda5     ( /home) Last dump: never
  /dev/sda1     ( /boot) Last dump: Level 1, Date Wed Nov  5 17:00:53 2014
用dump 备份非档案系统，亦即单一目录的方法
[root@localhost ~]# dump -0j -f /root/etc.dump.bz2 /etc
  DUMP: Date of this level 0 dump: Wed Nov  5 17:02:54 2014
  DUMP: Dumping /dev/sda2 (/ (dir etc)) to /root/etc.dump.bz2
  DUMP: Label: /
  DUMP: Writing 10 Kilobyte records
  DUMP: Compressing output at compression level 2 (bzlib)
  DUMP: mapping (Pass I) [regular files]
  DUMP: mapping (Pass II) [directories]
  DUMP: estimated 58325 blocks.
  DUMP: Volume 1 started with block 1 at: Wed Nov  5 17:02:55 2014
  DUMP: dumping (Pass III) [directories]
  DUMP: dumping (Pass IV) [regular files]
  DUMP: Closing /root/etc.dump.bz2
  DUMP: Volume 1 completed at: Wed Nov  5 17:03:09 2014
  DUMP: Volume 1 took 0:00:14
  DUMP: Volume 1 transfer rate: 516 kB/s
  DUMP: Volume 1 64590kB uncompressed, 7232kB compressed, 8.932:1
  DUMP: 64590 blocks (63.08MB) on 1 volume(s)
  DUMP: finished in 13 seconds, throughput 4968 kBytes/sec
  DUMP: Date of this level 0 dump: Wed Nov  5 17:02:54 2014
  DUMP: Date this dump completed:  Wed Nov  5 17:03:09 2014
  DUMP: Average transfer rate: 516 kB/s
  DUMP: Wrote 64590kB uncompressed, 7232kB compressed, 8.932:1
  DUMP: DUMP IS DONE


[root@localhost ~]# restore -t [-f dumpfile] [-h] <==用来察看dump 档
[root@localhost ~]# restore -C [-f dumpfile] [-D 挂载点] <==比较dump 与实际档案
[root@localhost ~]# restore -i [-f dumpfile] <==进入互动模式
[root@localhost ~]# restore -r [-f dumpfile] <==还原整个档案系统选项与参数：