Symantec Netbackup keeps using same tape/media to write on

[Meritus]

Hi,

i have a Symantec Netbackup 7.1 Enterprise installed.

Problem is - Netbackup keeps overwritting / writing onto the same tape despite the entire list of free tapes/media (label as TAPE01 - TAPE20) i have in my volume pool.

Is there something that i am missing ?

my volume pool have > 20 tapes yet netbackup keeps writing on the very first tape (which is TAPE01) on the entire list instead.

I am on a auto loader with >20 tapes in the loader. Policy is set as Full backup with retention period of 2weeks

Any idea what am i missing ?

[Andy_Welburn]

until it is full, at which point it will utilise the next available media.

If your daily backup policies all use the same volume pool & all have the same retentions then they will use the same media each day until full.

[Marianne]

NetBackup is not overwriting your tapes - it keeps on appending until the tape is full. As long as the media server, pool, density and retention level are the same, it will keep on appending.

See this TN for detailed explanation: http://www.symantec.com/docs/HOWTO33982

[Meritus]

hi, thanks for all of the quick reply.

make it simple...

i want to do it this way

daily use 1 tape (mon-sat differential)

weekly use 1 tape (sun full backup)

is there a way to do it as the above?

i have a total cycle of 3 x 7 tapes. (thus retention period is about 2weeks for all of the tapes) - correct me if i am wrong.

Anyway what is catalog tape for and is it compulsory to have it ?

thanks.

[Meritus]

hi, thanks for the quick reply.

but i am still not clear to some of the following...

as of below.

[Andy_Welburn]

Have one volume pool for "Daily" & one for "Weekly" - tapes will be drawn from media within each pool.

Catalog backup is essential (can go to disk) - this backs up config & image catalog to restore your NetBackup environment in the case of a DR situation.

[Andy_Welburn]

but nice to see this detail is 'now' all in one tidy little T/N!

[Meritus]

hi,

thanks once again.

i have configured it as such but still it doesn't seem to move on to the next tape

eg.

it continues to write onto the same tape - for daily it should be (Tape01 to 06) and weekly will be (Tape07, 14, 21)

i have configured the schedule to run on sunday...

but for both Monday and Tueday it continues to write on Tape01 which is not what i want. It should be writing on Tape02 instead for Tuesday.

if i tested it with "manual backup", will i be able to see the results (if i hv performed it twice on the same daily policy?) - as to what i wanted?

thanks

[Andy_Welburn]

which is not what i want."

You would need to have a separate Volume Pool for each day.

***EDIT***

Volume Pool "Monday" - Tape01 - Monday Schedules in Policies set to use this volume pool
Volume Pool "Tuesday" - Tape02 - Tuesday Schedules in Policies set to use this volume pool
Volume Pool "Wednesday" etc etc etc

***end of EDIT***

Do you really need to micro-manage your tapes this way? We used to initially, but have now reduced the number of volume pools we utilise & let NB manage our tapes (that's what it's there for afterall!). The more volume pools you have the more tapes you will need - there must always be AVAILABLE tapes within each volume pool (or Scratch Pool from which they could be drawn) or jobs will start to fail with EC=96.

[Meritus]

Is Company's policy... they "want" this and that

all i can do is to follow and they are willing to spent (btw i have close to 50+ new LTO-4 tapes at my disposal) - and the company wants me to utilise them all, effectively.

but now it is not moving onto the next tape...

lets us just say, even if i create 6 more volume pool.. which covers from Mon - Sat

My current Monday Tapes:

Monday Tapes: Tape01, Tape08, Tape15

even if i set it to individual volume pool, when the 2nd Monday comes, it will continue to write on Tape01 instead of Tape08? Then this will not solve my problem....

[Andy_Welburn]

would be to remove the media or "suspend" it once written to. You would then have to ensure that you reloaded the media or un-suspended it prior to the next time it is required. This is obviously so open to mis-management & human error.......

Can you not put forward the argument that the money (a lot) has been spent on the software, let it do its job?

***EDIT***

"and the company wants me to utilise them all, effectively." - then you (they) need to let NetBackup off the reins!

[Marianne]

Another way is to take tapes out the robot on a daily basis and send it offsite or put in a safe for safekeeping.

Use Tape Summary report (with Verbose checked) to see when images on tapes expire. Only put tapes back in the robot after expiration.

With only 20 slots in the robot you will probably have to exject tapes because of the amount of tapes that will be needed to keep backups separate.

[Meritus]

no plans to do it at this point of time.

the auto loader we have can carry a maximum load of 50 tapes at any one time.

any ways to automate it without the need to eject the tapes?

[Meritus]

chill bro,

you have to ask my company the question and not me  - i am just an employee.

seems like netbackup is a wrong investment since i have to work with it and not it works like how i preferred it to be

so there is not way to automate it right ?

[Andy_Welburn]

on a specific day?

What happens, then, when Tape01 is FULL or has a failure & can no longer be written to - all the Monday  week1 backups will fail, unless NetBackup is given the option to utilise other tapes.

Personally, I do not think it is a good idea to be so restrictive with the application - let the software do the job it was bought for i.e. backups & tape management.

[Meritus]

so... you are saying...

eg, for Monday

i will have a Volume pool on Monday which comprises of only Tape01, 08 & 15...

so i just let netbackup to handle which tape to backup over until it max out ?

meaning i can set a even longer retention period for each daily backup right since if i set 2 weeks and my current data is a mere 100GB+ (set to increase as time goes by)

it will keeps overwriting onto the same tape if retention is not up and not full and else if full, it will move over to Tape08 if the retention period is not up right ?

thanks

[Andy_Welburn]

NetBackup will keep writing to tape until it is full, even if it takes a year!

It will not be able to write to that full tape until ALL of the images on it have expired - this will be based on the retention period of the last image(s) written (probably a further 2 weeks from what you are saying - but longer if you increase the retention period)

[Meritus]

apologize that i keeps saying its "overwrite" when it is actually appending... too used to using it to customers.

anyway thanks for the guide, somehow i feel that i will highlight this to my superior and see if we can find a agreement towards this.

thanks all once again.

[Marianne]

The need for separate tapes for each day really comes from MANY years ago when we were were first introduced to backups - we had to use OS commands, manually label the tapes (Monday, Tuesday ....) so that we knew which tape to load and overwrite every day.

Now that we invested lots of money in a superior product, there is no need for this kind of micro management. NBU knows which backups are written where on which tape - no need for backup admins to keep track.

Hope you can convince your management! Maybe show them this thread...

[J_H_Is_gone]

What are they really wanting?

You said they want to use the tapes effectively - well that could mean using the whole tape and not just a small part - so you append to the tape until full.

Do they have any DR plans - most people put one days backup to a tape in order to take the tape out and send it off site - so if your building is damaged some how - you can rebuild your NB server and have tapes to restore your other servers.  Leaving all backups on site - makes you afraid of fire or other disasters.  In the same vain this is why you should make a catalog backup each morning and send it off site as well so you can use the catalog tape to rebuild your NB server - so you can use those other tapes to restore your other servers.

So if you backup to any tape each night - eject and send off site - you are doing the best you can to keep data safe (think about encrypting the tapes).  Have the tapes come back after they reach their expiration date and put them back into the library to be written to again.  NB will keep track of what backups are on what tape you just need to know when each tape expires and have it come back when it does.  If you have a two week retention that you can easily say when you send the tape off to bring it back in two weeks.

Seems to me you are tying too hard - NB helps keep track of a lot of stuff for you - Like Marianne says in the old days we had to keep track of each Monday tape - will the NB software will tell you what tape the Monday backups are on.