Am 2013-12-07 10:04, schrieb Robert Schetterer:
Am 07.12.2013 08:53, schrieb Claus:
Thanks for your suggestion to use maildir, but
i'm sure the key problem are the large Number of small files.
the backup goes first to diskstorage and afterwards to LTO4 Tapes.
We backup with EMC-Networker. The backuptime of large files (some GB)
are normal.
I wonder if there is no one who operates a large Mailsystem with mdbox
and has suggestions to backup this?
you are able to backup and restore mdbox with dsync ( never tested ),
but its not like with maildir simply i.e rsync the mailbox or one only
mail
so you may find some combined strategy using both formats depending to
your kind of storage, as people said i wouldnt recommand backup to tape
in a direct way
Thanks Robert!
As i wrote the backup goes first to diskstorage and than to tape.
why not simply do some testing with only one mdbox mailbox , should be
easy with dsync
Claus
Am 06.12.2013 11:51, schrieb Nick Edwards:
Claus,
Robert's suggestion is good, we backup maildir, with 5.9TB in 2 hours
to SATA , we also run a backup of that backup, so we have two extra
copies (this is on top of NAS snapshots)
tape is just too slow for anything serious these days.
N ik
On 12/5/13, Claus <clau...@bayern-mail.de> wrote:
Am 02.12.2013 20:37, schrieb Robert Schetterer:
Am 02.12.2013 18:47, schrieb Claus:
Hello,
i have to backup (tape library) a mailsystem with about 300.000
Mailboxes on 2 backends. Summary of all mailboxes are 2 TByte.
The mailstore is mdbox.
Is it save to do a simple filesystem backup (full and incremental)
with
backupsoftware?
hm i wouldnt do that with mdbox, cause it does strongly depends to
index, but if you use dsync you could convert to maildir at backup,
maildir should be fine to store on tape, but with 2 TB this is only
good
for total desaster archive, i guess it would take long time to
restore
specially single mailboxes in acceptable time, from tape
Better use cheap sata storage raids for frequent backups, and do
tape
snapshots sometimes.
What is the prefered strategy to do a backup for desaster recovery
(mailsystem crash) and restoring single usermailboxes?
dsync should do fine
http://wiki2.dovecot.org/Tools/Dsync
but there is no universal answer to this, perhaps filesystem
snapshots
strategy might better, it depened on your general setup ,
filesystems ,
mailstore etc.
wait for others report their solutions, and find the one fits best
at
your place
Regards,
Claus
Best Regards
MfG Robert Schetterer
thanks for your answer,
the main reason we plan to use mdbox is to reduce backuptime.
Now we are using Maildir on cyrus and the (full)-backup takes about
20
hours on one backend storing 150 GB of Mails in about 3 million
files.
Because of that we have many backends, so we can parallelize the
backup
prozess.
greets, Claus
Best Regards
MfG Robert Schetterer
