07-05-2019 06:03 AM
We have two NetBackup 5240 appliances running 3.1.2 (NB 8.1.2). Each appliance has dual FC ports for tape backups. We also have a tape library with 6 tape drives and each drive also has dual ports. All these are in a SAN First port from each appliance is zoned to East Swtich & Second port from each appliance is zoned to West switch. Same way one port from each tape drive is zoned to East Switch & second port from each drive is zoned to west switch.
In simple terms, each appliance can see 6 drives in two different paths. Is there a path policy setting like round robin on the NetBackup side so that both NetBackup appliance ports are used for load balancing ?Although there are two ports on the appliance side and each can see 6 drives, at any given time only one appliance port is being effectively used and other one is idle.
The above design was done keeping in mind redundancy at each level.
07-05-2019 06:10 AM
We use SLPs for tape duplication , so backups always happen from appliance to tapes.
07-08-2019 01:30 AM
NetBackup does not provide automatic SAN path failover for tape drives connected through multiple paths.
This applies to BYO media servers as well as Appliances.
See https://www.veritas.com/support/en_US/article.100012111
As far as I know, nothing has changed since the TN was published in 2014.
07-08-2019 03:10 AM
Hi Marianne,
Thanks for your response. We are actually looking for load balancing not path failover. Although both the appliance ports are zoned and can see all drives in both the paths, during duplication only one port is used which is showing up more load on one particualr port of SAN switch (which is obvious). Do we have any path policy like Round Robin or Least recently used etc while using tape drives if there are multiple paths available so that all ports of appliance are effectively used.
07-08-2019 04:46 AM
Path failover as well as load balancing is part of multipathing capabilities.
NetBackup does have built-in multipathing software or support 3rd-party tape multipathing sotware.
These old forum posts still apply (bearing in mind that Veritas is not developing anything new for tape):
https://vox.veritas.com/t5/NetBackup/multipathing-fiber-switches-in-NetBackup/m-p/441749#M96863
https://vox.veritas.com/t5/NetBackup/Zoning-of-tape-drives-with-Media-Server/td-p/770232
https://vox.veritas.com/t5/NetBackup/DRIVE-LOAD-balance/td-p/524732
Please ignore any Symantec URLs in above posts - they do not redirect.