Seagate FreeAgent
I bought a Seagate FreeAgent 320GB external USB drive this weekend and finally put an automated backup system in place. Steps involved:
- The FreeAgent comes pre-formatted as a NTFS drive. I reformatted it to ext3.
- The drive goes to sleep after some period of inactivity. The current kernel doesn’t automatically wake it up so you get I/O errors when writing to the disk after it has gone to sleep. The fix is simple.
- I created a list of directories to backup and then created a couple of cron entries to run rdiff-backup every morning.
root@cellar:~# crontab -l 30 4 * * * rdiff-backup --remove-older-than 3W /mnt/freeagent/cellar-backup 2>&1 >/dev/null 50 4 * * * rdiff-backup --exclude-fifos --exclude-sockets --include-globbing-filelist \ /home/antrix/backup/rdiff-backup-filelist / /mnt/freeagent/cellar-backup 2>&1 >/dev/null
Now I’ve got daily backups with an option to retrieve stuff from upto three weeks earlier. Seriously, this was so easy, I wish I’d done it sooner. Thankfully, nothing catastrophic occurred in the meantime! Plus, this is a live backup - much better than burning CDs marked with Photos from 2006, etc.
For reference, here’s rdiff-backup-filelist:
antrix@cellar:~$ cat backup/rdiff-backup-filelist
- /home/antrix/.mozilla/firefox/**/Cache
- /home/antrix/.thumbnails
- /home/antrix/.local/share/Trash
- /home/antrix/tmp
- /home/antrix/Downloads
/home/antrix
/etc
/share/Books
/share/Music
- **
antrix@cellar:~$
The performance of this drive seems pretty good considering it’s just a USB 2.0 unit. Raw disk throughput on this 7200RPM disk, as measured by hdparm -t -direct /dev/sdc, averaged 29.4 MB/sec. I could push this up to 33.4 MB/sec by setting max_sectors to 1024. For comparison, the internal SCSI disks (also 7200RPM Seagates) averaged 74.7 MB/sec.