400GB Tape

[Amaraa]

Hello there,

We are using 400Gb tape for backup. Our backup size is approximated 370Gb.
400-370=30Gb Free space. it is true or not 30Gb space used for file system.

[Ivan Ferreira]

>>> it is true or not 30Gb space used for file system.

¿Can you explain a little better your question?

[Amaraa]

Our backup size full 370 and we left about 30Gb space.
I'm try to backup incremental backup to 30Gb space. Incremental backup size is 200Mb or 1Gb something like that. But cannot backup to 30Gb

Sorry my poor english

[Aneesh Mohan]

Hi,

Which software you are using for backup ? Is it Dataprotector or some other backup software ,if so you can use the entire capacity of the media.

Aneesh

[Amaraa]

We are using on linux OS.
uname -a
Linux AAA2 2.6.5-7.244-bigsmp #1 SMP Mon Dec 12 18:32:25 UTC 2005 i686 i686 i386 GNU/Linux

Backup software is just script.
Our backup schedule.

Mon - Incremental
Tue - Incremental
Wed - Incremental
Thu - Incremental
Fri - Full new tape
Sat - Incremental
Sun - Incremental

Full backup size is 370Gb. Our tape is HP Ultrum C7972A. Tape Size is 400GB.
Sat and Sun incremental backup is always failed.

[Amaraa]

AAA2:~ # df -h
Filesystem Size Used Avail Use% Mounted on
/dev/cciss/c0d0p4 19G 611M 17G 4% /
tmpfs 1.5G 52K 1.5G 1% /dev/shm
/dev/cciss/c0d0p1 198M 11M 178M 6% /boot
/dev/cciss/c0d0p7 5.0G 635M 4.1G 14% /opt
/dev/cciss/c0d0p8 3.0G 909M 2.0G 32% /tmp
/dev/cciss/c0d0p5 5.0G 1.6G 3.2G 33% /usr
/dev/cciss/c0d0p6 30G 2.0G 27G 7% /var
/dev/evms/POOL1
411G 340G 71G 83% /opt/novell/nss/mnt/.pools/POOL1
admin 4.0M 0 4.0M 0% /_admin
SITEFS 250G 238G 13G 96% /media/nss/FS
SITEHOME 150G 101G 50G 68% /media/nss/HOME

[Torsten.]

Your tapes have only 200GB native - 400GB is marketing assuming a compression of 2:1. If your data cannot be compressed that much, you cannot store this theoretical amount of 400GB, but less.

[Wei Jung]

With a script, it wont backup system state. That is depending of the backup software.

So are they 200/400GB tapes or 400/800GB tapes?
Because indeed, those compressed capacity are assuming 2:1 compression ratio, which sometimes cannot be achieved, or sometimes can be higher than that, depending of the type of data being backed up.

[Amaraa]

On the tape cover HP Ultrium 400Gb Data cartridge C7972A. Also

*Assuming 2:1 compression

This is mean 200/400Gb or 400/800Gb?
i think this 200/400Gb?
That's right?

Thanks
Amaraa

[Torsten.]

C7972A is ultrium-2 200GB native 400GB compressed with 2:1 (in real life typically less).