Development Page--Not for Official Use

This document describes the backup strategy used by CBI-DNR.

What's backed up

meridian

 /u2 - All user directories for DNR
 /var - The LDAP database, the DNS database, mailboxes

dnr

 /u4 - pobot (the account that handles automated data downloads)
 /u3 - clerk (archiving/decoding), cbidb (holds information about the stations that doesn't fit into the MySQL? database)

When it's backed up

meridian

tape backups run on this machine at 2:00am every day.

dnr

tape backups run on this machine at 4:00am every day.

Backup time is approximately 2 hours.

How it's backed up

Both meridian and dnr are backed up using the standard linux tar command. Here are the crontab entries for each:

meridian

	
# Backup /var, /u2 once a day
0 2 * * * time tar cvf /dev/st0 /var /u2 2>&1

dnr

	
# Backup /u3, /u4 once a day
0 4 * * * time tar cvf /dev/st0 /u3 /u4 2>&1

Backup Philosophy

We use a variation on the 10-tape backup method some times called "Grandfather,Father,Son" where each tape is labeled thusly:

1. Monday
2. Tuesday
3. Wednesday
4. Thursday
5. Friday 1
6. Friday 2
7. Friday 3
8. Month 1
9. Month 2
10. Month 3

where the Month 3 tape is rotated out to off site storage. This gives quarterly snapshots of all of our data.

The labels on the tapes refer to the day the tape is removed from the drive. So, for instance, the tape labeled "Monday" is actually placed in the drive on Friday because backups will happen over the weekend with the last one on Monday morning (barring incident over the weekend).

Bibliography

	http://www.lanscape.com.au/Support/backup.htm
	http://www.ate.net/pages/tape_backup_strategy.htm
	BackupEmail? - correspondence between TommyWhite? and PatrickMichaud?