SAN config having both physical tape and VTL

[turdb0]

How would you design the backup environment with the following:

Two (2) SAN switches: SwitchA and SwitchB

One (1) TSMserver: fcs0 and fcs1
Four (4) AIX servers (DB2): fcs0 and fcs1

One (1) TS3310 Library with Two (2) 3580 drives --
3580 Drive1: fiber port1
3580 Drive2: fiber port1

One (1) Data Domain DD610(with VTL) with 2 ports: hba0 and hba1


I want to backup to disk(DD610 VTL option) over SAN, and also keep a copy on tape(TS3310) over SAN. I read that the DISK and TAPE should be on separate ports. Easiest would be to Zone all "disk" related through one SwitchA and zone all "tape" through the other SwitchB, right?

What do you guys recommend?

 

[Mikey D]

Best practices would be to have each switch act as a separate fabric, run half the cables for the VTL to switchA and the other half to switchB, same with the disk and tape library. To do this though you'd need four HBA ports on each server for tape and vtl, add in SAN disk and you'd need another two ports unless you're doing stuff with vio already.

Having these switches in separate racks too with separate power is the best idea.

 

[turdb0]

In a perfect world, i'd consider what you said. But I'm left do with what I have now. So i'm just planning to put the physical tape drives on switchA and the VTL device on SwitchB. The power redundancy is being achieved using separate PDU's.
Thanks.

 

[jharris]

I'm not 100% familiar with the DD610 product as we're a total IBM shop here and use the Protectier VTL. But if the DD610 has the software running VTL emulation then effectively it's a tape library, not a disk storage device (even though the volumes are virtual and stored on disk).

So the primary reason to seperate disk and storage I/O onto different HBA ports is that the nature of the traffic and packet sizes differ. But, when communicating with a VTL, the nature of the traffic should be similar to that of your LTO library.

Hence, there is no reason to really seperate the VTL from the LTO onto different HBA ports.

You have 2 switches, for SAN redundancy, each server has two HBA ports, allowing a foot print in both SANS and you can setup TSM to have primary storage pools defined on the VTL with migration to a secondary storage pool on the LTO. Alternatively, if you have enough storage with the deduplication feature of the VTL, you can keep your primaries in the VTL and make copies of those volumes to the LTO (not sure if its offsite or onsite).

Does that make sense?

 

[jharris]

Additionally, to my post above ... if all of the servers have been zoned into the DD610 and have the device drivers installed for the VTL emulation, then you could install lan-free storage agents on your TSM clients and send their backup data via SAN (not via ethernet through the TSM server) to primary storage pools on the DD610. This could again be later copied or migrated via a TSM housekeeping process to the LTO tapes.

This may be necessary if your TSM server ethernet interfaces are a bottleneck for your nightly backup requirements.