Marc, My experience is with the HP library, but DLT instead of LTO. The issues we ran into are not media or drive specific.
TSM 4.1.5.0 on AIX 4.3.3 ML 8. HP SureStore 4/40 DLT 8000, four drives, diff SCSI We've seen two serious problems that you'll have to watch out for: 1) Library firmware and TSM "adsmtape" driver can get out of sync. This causes total failure of the library in TSM. 2) The library controller cannot handle the flood of data passing through it when it is in the middle of the SCSI chain. Details: 1) On initial setup or our HP library, we ran into lots of problems because the "adsmtape" driver shipped with early version of TSM 4.1 received more data from the library firmware than it was expecting and that caused the library to be literally unusable with TSM, despite its being listed on the "supported devices" list and passing its own diagnostic tests. Investigation revealed that the TSM driver had been certified with the base release of the library firmware. HP Tech Support gave us the secret password to down-level the library firmware to what the driver supported until TSM development provided an updated driver with TSM 4.1.4. Then we went back to the current firmware release and everything has been working fine since. But there is nothing that says this situation cannot recur. 2) We initially cabled our library like: TSM Server -> lib ctlr -> drv 1 -> ... -> drv 4 -> term. That's how all of our IBM libraries are cabled (with no problems). But the HP had numerous problems that usually showed up as I/O failures on drive #1, and which continued even when the drive was replaced. I finally fixed the problem by cabling as: TSM Server -> drv 4 -> ... -> drv 1 -> lib ctlr -> term. That way the controller is at the end of the SCSI chain and the drive data does not pass through it. HP Tech Support thanked me for the info and admitted that that scheme might solve several nagging problems they had been fighting with. Operationally, it has been a good unit since we got the problems above solved. We DID have to replace the picker assembly two months ago, but over the last six months we lost the pickers in all four of our libraries (two 3575s, a 3583, and the HP 4/40). We use our library for creation of offsite tapes. It is VERY handy for that because you can open any or all of the tape magazines while the unit is in operation. And the "Map" function of the front panel shows the location of every tape on a tier at one time, so in our case, I can inspect the entire library with two button presses. There is no comparable function on any of our IBM libraries. One other thing to be aware of is the synchronization between the library and "replies" to TSM. When you pull a tape from the HP, then close the magazine that carries the "mail slot" (I/O slot), the library rescans the slot and the status light is red. If you "reply" to TSM while the libary is in that state, TSM will accept the reply, but the library will ignore the subsequent "move" command forcing you to pull the next tape via the library front panel. This is something we worked around via procedure, saying "wait until the icon view returns to the library LCD front panel." The odd thing is that the library continues to accept data while that light is red. Hope all of this helps. Tab Trepagnier TSM Administrator Laitram Corporation "Marc D. Taylor" <[EMAIL PROTECTED]>@VM.MARIST.EDU> on 06/13/2002 11:37:29 AM Please respond to "ADSM: Dist Stor Manager" <[EMAIL PROTECTED]> Sent by: "ADSM: Dist Stor Manager" <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] cc: Subject: LTO Offerings (was Library Survey) Hello Again, Before this thread gets away from me, let me say a few things. 1. From the email postings to this group it appears that the IBM LTO drive is what most people use if they are using LTO. I understand that IBM makes a fine product and it gives me warm and fuzzies if I had a chance to choose the IBM LTO drive. Also from the postings, IBM has had it share of teething pains in the earlier days of this technology. 2. I guess I would really like to hear from the people on this list (whoever you are) who chose a library with the Seagate or the HP LTO drives and what their experiences have been, good or bad. If no one on this list has purchased tape libraries with Seagate or HP LTO drives then that is telling also. Sorry if my previous post was not focused enough. Marc Taylor
