Fbackup

[Nobody's Hero]

OK, We purchased a new RX Itanium server running 11.23. Box is Hpar'd in 2 partitions.
I am running an fbackup on all root filesystes and our /app area, excluding all other areas. Total should be about 20-some gig. Should easily fit on a DDS4 tape.

Keeps asking for a second tape:

I tried /dev/rmt/0m
and I tried
/dev/rmt/c4t1d0BEST to get compression.

Still asks for a second tape:
Here is my bdf:
/dev/vg00/lvol3 524288 228544 293464 44% /
/dev/vg00/lvol1 311296 107496 202256 35% /stand
/dev/vg00/lvol8 4718592 1523488 3170192 32% /var
/dev/vg00/lvol7 5947392 2489312 3431128 42% /usr
/dev/vg01/lvol9 104857600 49194314 52184336 49% /u09
/dev/vg01/lvol8 78643200 43166889 33259110 56% /u08
/dev/vg01/lvol7 62914560 22559945 37832458 37% /u07
/dev/vg01/lvol6 62914560 15166117 44764217 25% /u06
/dev/vg01/lvol5 62914560 25378846 35189733 42% /u05
/dev/vg01/lvol4 41943040 20619437 19990884 51% /u04
/dev/vg01/lvol3 41943040 13656177 26518986 34% /u03
/dev/vg01/lvol2 41943040 1166519 38227994 3% /u02
/dev/vg01/lvol1 41943040 2188767 37269637 6% /u01
/dev/vg00/lvol4 1048576 520384 525096 50% /tmp
/dev/vg00/lvol6 3915776 2291448 1611656 59% /opt
/dev/vg00/lvol5 32768 22272 10464 68% /home
/dev/vg01/lvol10 41943040 24648893 16213331 60% /app
ihshp6:/DLT 79515648 74105912 5409736 93% /NFSHP6

Here is my graph file:
i /
i /stand
i /var
i /usr
i /tmp
i /opt
i /home
i /app
e /u01
e /u02
e /u03
e /u04
e /u05
e /u06
e /u07
e /u08
e /u09
e /cdrom
e /net
e /NFSHP6

Here is my backup command:
/usr/sbin/fbackup -0 -f /dev/rmt/c4t1d0BEST -g /root/bin/graph_ltcps1

[Robert-Jan Goossens]

Hi Robert,

Total backup is about 32 GB. Maximum capacity of a DDS4 is 40 GB compressed 2:1. Actual capacity is between 20 and 40 GB, depending on how much compression you can get on your files, old or new tapes, how often you clean your drive etc etc etc. I your case the actual max capacity is lower.

There are more threads in the forum, search google itrc dds4 capacity

http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=880530

Check Bill's answer.

Hope this helps a bit.
Robert-Jan

[A. Clay Stephenson · Accepted solution]

Note that /app alone is 24.6GB. The native capacity of a 150m DDS4 cartridge is 20GB. Your result is not at all surprising. The 2:1 compression ratio that is the industry "standard" is nothing more than a marketing guess. Some data compress far more than 2:1 and some data compress far less. Whenever you are calculating media requirements, it's always prudent to assume native capacity and if you get more than that, it's gravy.

[Nobody's Hero]

Ok,
Then how would you recommend backing this up, without going to a DAT72?

Can you pipe fbackup to some kind of compression?

[A. Clay Stephenson]

Yes, fbackup can write to stdout so you could feed compress via a pipe BUT you are missing the point. What makes you thing that an external compression command will do a significantly better (or worse) job on your data than the hardware compression on your drive?

You have several options:
1) Divide and conquer so that your existing backups will fit on a single tape. Of course, this would require 2 fbackup runs.
2) Larger capacity tape drive
3) Multiple tape drives. Note that fbackup does allow multiple -f xxx options so that when the first medium is full, the remainder of the output is shifting to the next -f device specified.

[Bill Thorsteinson]

You shouldn't need to backup /tmp. It should
contain nothing required after a reboot.

/, /stand, /usr/, /opt/ could be covered on
an ignite recovery tape. These directories should be stable. Redo after each
software installation or configuration
change in /etc.

That leaves you with /app, /home, /var.

If you using NFS to get home directories
from another server, then you should be able
to included /home on the ignite tape.

You are then down to backing up /app and /var.

Depending on how vital log files are
considered, you can move this to ignite.
/var/spool should have stable content
except for crontabs if you use them.