> I'm currently using 4 TB partitions with vxfs. When hosted on FreeBSD
> I was limited to 2 TB but using UFS2/FreeBSD was impractical for
> several reasons. With vxfs 4 TB is a practical limit, when files are
Could you please give some hints on these reasons? I only know that
FreeBSDs UFS2 is not fully 64 Bit aware.
FreeBSD 5/6 can under normal circumstances perform a fsck in the
background if the server had an unplanned restart. But before it can
do so it has do make a snapshot. A snapshot would take approx. 20 min.
on a 400 GB partition and during that time the webservers could not
access the nfs-server and hence our visitors would see an
error-message. As my partitions grew the time taken to perform a
snapshot would also increase.
At that time FreeBSD did not have a volume manager (it may have now)
and jugling with number of disks in a raid-set so I could make
partitions reach the 2 TB size and still make them almost the same
size and not waste too much disk space was a bit of a pain. Growfs
would not always work, jugling with sizes in bytes and manually edit
the partition can result in erros if one is not careful.
Using veritas vol.man. is more a matter of adding the LUN's to a
diskgroup and then create the partitions with that dg. Much easier.
Zpool and zfs create is easier than veritas.
> stored on the volume we take incremental backup every night, and this
> requires approx. 16-17 LTO-3-.tapes. When a partition is filled up we
> perform a complete backup which requires approx. 12 LTO-3 tape. Our
> tape-station is a Dell PV136T with 3x18 slots. Increasing a partition
> to 5 TB would require more tapes and I don't have any plans on
> becoming a tape-dj :-)
What kind of backup software do you use and what amountof time does a full
and an incremental backup take?
I use legato networker. They have drivers for solaris 9 on sparc for
lto-3-tapes.
Could you please explain why an incremental backup takes 16-17 tapes while
a full backup only takes 12 tapes?
It's because some of our users do minor changes to their files and all
these changes to individual files will be added to the incremental
backup. So a file can be backed up more than once.
12 tapes with 400 GB should pe OK for a level 0 backup of a 5 TB volume.
I see the size of an incremenatal backup is less than 4% of the total data size
on the NFS server for berlios.de. In your case, this should be less than 180 GB
which is less than one single tape. Do you use GNU tar for your incrementals?
I use legato.
--
regards
Claus
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