So in your setup is each tape drive has both ports used, with each to a separate san's. You mentioned 4 HBA's - is that 2 into each SAN? If so, then do you have 4 RMT devices for each tape drive?
Rick -----Original Message----- From: ADSM: Dist Stor Manager [mailto:ADSM-L@VM.MARIST.EDU] On Behalf Of Steven Harris Sent: Wednesday, October 15, 2014 8:24 AM To: ADSM-L@VM.MARIST.EDU Subject: Re: Load balancing when you have many virtual tapes? Rick I have a recent set up, TSM 6.3.4.300 on AIX 7.1, LTO5s and I too always thought that the atape driver did load balancing. However I have one port on each drive connected to one SAN and one port connected to a second SAN and I can see what port is being used because of which HBA the traffic goes down: in my environment I don't have access to the switches to be able to monitor there. All of the TSM paths were defined using devices on the same SAN as I thought load balancing meant this would not matter. As it turns out the one I chose has a performance issue. Looking closer I saw that all the traffic was going down the devices as defined in the path, and none on the other SAN. When I rmdev-ed the device on the SAN with the performance issue, there was a message that the device had changed, the TSM path was updated to the alternate device (which I did not expect) and subsequent mounts have been on the alternate path. HTH Steve Steven Harris TSM Admin Canberra Australia On 14/10/2014 4:08 AM, Rhodes, Richard L. wrote: > What kind of drive are they emulating? Are they emulating IBM > drives with Atape driver? My understanding (I've been trusting > this for years) will auto load balance across hba's. > > Rick > > > > -----Original Message----- From: ADSM: Dist Stor Manager > [mailto:ADSM-L@VM.MARIST.EDU] On Behalf Of Erwann Simon Sent: > Monday, October 13, 2014 12:36 PM To: ADSM-L@VM.MARIST.EDU Subject: > Re: Load balancing when you have many virtual tapes? > > Hello Wanda, > > As TSM allocates drives in order, you have to distribute drive > between the HBAs in a round robin way (with 4 hba : drive 1 on hba > 1, drive 2 on hba... drive 5 on hba 1 and so on). I prefer doing > this at VTL level using mapping policy (i.e access groups on Data > Domain). > > Le 13 octobre 2014 18:28:36 CEST, "Prather, Wanda" > <wanda.prat...@icfi.com> a écrit : >> TSM 7.1.1 on AIX So I have a customer putting in a VTL, which >> will have 96 virtual drives. Those virtual drives will be spread >> across 4 HBA's. >> >> What sort of strategies to people use to keep TSM from starting >> a BACKUP stgpool process and picking 4 virtual drives all on the >> same HBA? Is it dependent on the order you do your DEFINE DRIVE >> commands? Better to set up multiple virtual libraries? >> >> Any suggestions appreciated. >> >> Wanda >> >> >> Wanda Prather | Senior Technical Specialist | >> wanda.prat...@icfi.com<mailto:wanda.prat...@icfi.com> | >> www.icfi.com<http://www.icfi.com/> | 410-868-4872 (m) ICF >> International | 7125 Thomas Edison Dr., Suite 100, Columbia, Md >> |443-718-4900 (o) > ----------------------------------------- The information contained in this message is intended only for the personal and confidential use of the recipient(s) named above. If the reader of this message is not the intended recipient or an agent responsible for delivering it to the intended recipient, you are hereby notified that you have received this document in error and that any review, dissemination, distribution, or copying of this message is strictly prohibited. If you have received this communication in error, please notify us immediately, and delete the original message.