Backup media choices for FreeBSD servers
rsmith at xs4all.nl
Tue Apr 24 15:57:13 UTC 2007
On Mon, Apr 23, 2007 at 05:01:17PM -0700, L Goodwin wrote:
> I need to implement an automated backup facility on the FreeBSD file
> server I'm setting up for a client. It will have a software RAID 1
> Mirror/Duplex that is made available to Windows XP SP2 and Windows
> Vista Home Premium users as a Samba share. I also plan to create
> system recovery disks (disk images) for the server and each Windows
> This leaves backing up user data on some schedule. I've read "Backup
> Basics", but have some questions:
> Which is best backup media for a FreeBSD file server, based on known
> issues (or lack of) with each format? I need to decide between the
> following formats:
> a) CD-R (or CD-RW?)
Too small these days.
> b) DVD-R (or CD-RW?)
Usefull, but you have to store them correctly or they won't last very long.
> c) Streaming tape (which format/standard?)
No experience with that, sorry
d) USB drive (disks are cheap)
This is what I currently use to back up my system. After mounting the
(geli encrpyted) disk I start a script that performs a dump(8) of all
ufs filesystems, compresses them with bzip2 and writes them to the
If you want a non-os specific data format you can use tar. Start with a
full backup, and after that use the --newer option, so every subsequent
backup only stores the files that have changed since the last backup.
> Which is the best method for backing up data files on a Samba sharer FreeBSD?
> Handbook says dump is the only way to go.
Dump works best for UFS filesystems. Tar handles normal files well,
but might have issues with device files, flags and ACLs, things that
dump does handle.
Copying the data straight to a FAT32 filesystem and you'll loose things
like ownership and permission.
> Is it possible to have a Windows client perform the backup files on
> the Samba share to a local Re-Writable CD or DVD drive?
Yes, if the client in question has access to all the data on the samba
share. but automation on windows is much more difficult than on FreeBSD.
> If the answer
> is YES, what are the pros and cons of a UNIX-based (data-file only)
> backup vs. a Windows-based one? Please add to my list of pros and
> Windows Backup:
> PRO: Backup can be restored to a Windows drive while server is being fixed?
Not if you're using dump. Winzip can handle gzipped tarfiles.
> CON: Users might forget to replace backup disk after using optical
CON: cannot be automated properly.
CON: windows programs won't handle things like UIDs and permissions properly.
> FreeBSD Backup:
> PRO: Out of sight from users (server is in a storeroom).
PRO: Can be don with minimal user intervention.
PRO: Can store all the attributes of the native file system.
> CON: Cannot restore backup to a Windows disk while server is being fixed?
> These are some of my other considerations:
> 1) Cost is a primary concern. Budget does not allow for a multi-drive
> solution. Best if client does not handle backups (change
> discs/tapes), so a solution that permits storing several backups to
> same disc/tape preferred.
I think a detachable USB disk is very cost effective. A 500GB external
Seagate drive is $153 at newegg. You'd buy a couple and rotate them. A
tape drive alone would cost more.
> 2) I only want to back up user data (not the OS). Current user data
> occupies less than 1GB of drive space, and is expected to grow at a
> modest rate.
In that case a 500 GB backup disk could hold years of weekly full backups.
> 3) I do NOT have a writable CD or DVD drive (but can buy one if not
> too spendy).
Media durability is an issue. I've seen test in magazines where more
than half the discs contained a lot of errors or were unusable after two
years. I've also seen optical drives fail in under two years depending
on the environment.
> 7) Have not yet settled on a backup schedule. May be weekly or monthly
> or ad-hoc, but daily is probably out of the question. The RAID 1 array
> is expected to provide some degree of protection in leieu of daily
> backups. Plan to back up all documents each time, rather than
> implement a two-tiered backup process.
Mount an external USB, and create a cron job to copy the data over to it
every night. No user action whatsoever required. Make sure that the
external disk is not visible as a Samba share. Swap out the external
disk for another one every week or month (this requires user
intervention, but it could be scripted) and store the one not in use in
a safe or off-site.
How often you back up depends on how much work you're willing to loose
or redo, and how easy it is to replace/recreate the data . Too much
backups fills up cheap disk or DVD space. Not enough backups can destroy
your client's business.
[plain text _non-HTML_ PGP/GnuPG encrypted/signed email much appreciated]
pgp: 1A2B 477F 9970 BA3C 2914 B7CE 1277 EFB0 C321 A725 (KeyID: C321A725)
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Size: 187 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-questions/attachments/20070424/728872af/attachment.pgp
More information about the freebsd-questions