Video Screencast Help

SSO limitations and Usage

Created: 28 Jun 2011 • Updated: 12 Jul 2011 | 4 comments
This issue has been solved. See solution.

Hi all,

Just some small query regarding SSO in netbackup.I know that the license are required for the number of drives we want to share among multiple media servers but is there a limit on number of media severs that can be connected to one Drive. I am planning to connect about 30-40 on each drive. and what can be the impact of doing this even if this is possible. any best practices please share.



Comments 4 CommentsJump to latest comment

Nathan Kippen's picture

I don't know of any restriction on how many servers can share a tape drive.. though 30-40 sounds a bit crazy..  One of those 30-40 servers is the scan host which tells everybody else if the resource is available or not...   so everybody has to be able to talk to each other... 

I have up to 7 servers sharing a drive.

Symantec Certified Specialist
Don't forget to vote or mark solution!

J.H Is gone's picture

do you have 30 to 40 drives for all these servers to use?

Once one server starts using the drive - no other server can use it until it is done with it.

as you asked " limit on number of media severs that can be connected to one Drive "

this is yes if you say " connected at one time"  - only one media server can use a drive at one time.

As to the number of servers that can be SSO-ed to the drives on the robot - I don't know of a limit.

I don't have to know how to spell....I work on Unix.
NetBackup 7.0.1 - AIX & Windows

PraveenCH's picture

Hi Gaurav,

I think there is no limit to share a tape drive if you have SSO enabled.

But is it not sugested to share a single drive on 30- 40 servers, as if 1 media server is using this tape drive then rest all will be waiting for the tape drive till it is free. In this case there will be very high wait time for media servers. I dont think its a best practice to manage 30-40 media servers with 1 tape drive.

I suggest to make others a clients so that you can run multiplestreams at a time.


Anton Panyushkin's picture

Here is an excerpt from quite useful article that regards SSO limitations.

Don't go nuts with SSO! Among the myriad things Veritas doesn't tell you unless you know the right people is that at around 250 instances of devices you will have weird device problems (25 tape drives shared among 10 media servers would make 250 instances). The safe number is closer to 150. Ignore this at your peril.

Article Source: