Forum Discussion

kabacsk's avatar
kabacsk
Level 3
10 years ago

tape selection for backup at diff inc. backup

Dear All,

I have label my tapes as standalone to my tape drive.
I have set the backups for diff inc , cum and full backup for two policies.
My problem is when I set a second diff inc backup in policy with retension 1 year to use the same tape on saturday diff inc and sunday full backup without changing tape (because same retension needed without tape change), The backup did not start becacuse according to logs it wanted a different tape. Can I solve this issue if I just set retension period to 8 =1 year on that tapes and on other tapes of weekday daily backups to 1 week. Shall it knows what tape to select? If I put in a tape for monday backup will it use or want a possible different tape to continue to use. I emphasise I do not use robot. Is there a startegy how to avoid tape reasource problem?

I hope I was clear.

thanks

Karoly

  • If there is still space left on tape for same retention, NBU may request this tape instead of using new tape. If you want to prevent NBU from requesting already used tape, Suspend it. Either from cmd or in the Media GUI.
  • Run one fixed retention for all backup types (full,inc,cinc) or enable "Allow Multiple Retentions per Media". Mixing multiple retensions on tape is usually not best practice, but since you have no robot, cutting corner is sometimes needed. Before enabling, read this blog about how Netbackup writes to tape to understand the implication:

    https://www-secure.symantec.com/connect/blogs/understanding-how-netbackup-writes-tape

    Best Regards

    Nicolai

  • Dear Nicolai,

    Thank you for your reply. I have different tape for every day with the same retention period. However in weekend I use differnet tape with also other retension period.

    My question is if I have 5 tapes with same retention period and I put into the drive the next tape what come will netbackup knows that tapes has to be applied (used to copy ) and do not turn to other tape that is not in drive? Or do I have to 'force' somehow the nb to allow only one that has to come to use? like suspend other tapes use diff volume pools for diff tapes?

    any advice would help

    regard

    Karoly
     

  • If there is still space left on tape for same retention, NBU may request this tape instead of using new tape. If you want to prevent NBU from requesting already used tape, Suspend it. Either from cmd or in the Media GUI.