CITI: Backups

View backup logs by date: Backup Archive

Beginning with the November 2004 backup, the volume set and dump schedule names have been changed to be a bit more meaningful. The volume sets are defined as follows:

backup> listvolsets
Volume set all:
    Entry   1: server babylon.citi.umich.edu, partition .*, volumes: .*\.backup

    backup>

Which means that volumeset all includes the volumes on server babylon.citi.umich.edu, on all of its partitions (.*), which are named xxx.backup (.*\.backup).

The dump schedule is defined as follows:

backup> listdumps
/full 
    /wek1 
        /daily 
    /wek2 
        /daily 
    /wek3 
        /daily 
    /daily 
backup>

This schedule assumes that a full dump (/full) will be performed once a month. Weekly incremental dumps may be done in the intervening weeks. (/full/wek1, /full/wek2, /full/wek3) Daily dumps may be performed off the monthly full dump until a weekly is performed (/full/daily), or off of a previous weekly dump (/full/wek2/daily).

This has the effect of changing the name of the tapes. A full dump of the volume set all will have tapes named like 'all.full.1', 'all.full.2'. A weekly incremental may be named 'all.wek3.1'.

OpenAFS Backup Instructions

Disable the screamer incrementals by editing root's crontab on screamer to send a reminder rather than actually attempting its backups while the AFS backups are in progress.
SSH to got-back.citi.umich.edu, logging in as 'admutil'.
Once logged in, run screen. Some common screen commands used are:
```
	^A c - create new window
	^A n - next window
	^A p - previous window
	^A d - detach screen
```
where '^A' means 'control A'. For more information, man screen.
With screen up, run bin/logbackup in one screen.
Create a new screen window (^A c) and then run bin/logbutc
There are now two screens which can be toggled using '^A n' or '^A p'.
Backup commands may be executed now. See below for some typical commands.
At any time use '^A d' to detach the screen. You can do this, exit from got-back, come back to a new machine, ssh into got-back, run 'screen -r' and recover the old session.
After AFS backups are complete, re-enable the screamer incrementals by editing root's crontab on screamer to do the backups rather than sending the reminder.

Here are the typical backup commands that might be used to do a backup:

If a tape is being re-used, it must be re-labelled.
```
backup> labeltape all.full.1
```
Start a dump for the volume set named all. A full dump of each volume will be performed:
```
backup> dump all /full
```
Start a dump for the volume set named all. An incremental dump of each volume will be performed. Everything since the the last full dump will be dumped.
```
backup> dump all /full/wek1
```

Screamer Backups

The screamer backups are automated with scripts. /usr/local/bin/dump-to-got-back.sh is run out of root's cron and does daily incrementals. It assumes the incremental tape is in the drive, goes to the current end of data on the tape, and writes the new incremental. The script sends e-mail upon successful or unsuccessful completion.

When the incremental tape is filled, the automated dump will fail, and a new full (level-0) dump is needed. This is done manually by putting in a new tape to hold the full dump and running /usr/local/bin/dump-to-back-full.sh .

Handy commands:

Swapping out the incremental tape to do OpenAFS backups:
```
mt offline
```
Reusing a tape to be used for the screamer level-0 dump:
```
mt -f /dev/nst0 rewind
mt -f /dev/nst0 eof
```

Backups are run by kwc