Re: automating tbtape on Informix V5

Dana Lloyd (danal@austin.ibm.com) wrote: : Basically V5, aka tbtape, has a hard stop at 2.2GB. That's just the way : it is according to Informix. You have been misinformed. tbtape has a hard limit of 2TB. As far as I know (back to 4.x), tbtape has always had a limit of 2TB. I think there may have been a bug regarding ULIMIT (something like not resetting ULIMIT if backing up to disk), but even these should not affect backup to tape. The other limitation on tapesize for archives (besides 2TB) is that some OS flavors will count up the amount of data written between an open() and a close(), and since this is basically what tbtape uses, on these OS flavors, this can cause tbtape to fail at 2GB or 4GB (depending on whether the OS used a signed long or an unsigned long). So if you have a 7GB tape (is that where this originally started? I can't even find the original question), and you do NOT use one of those unfriendly OS flavors that cut you off at 2GB or 4GB, you can happily set your TAPESIZE to 7000000 (kbytes). (Although, we generally recommend setting it a bit lower than the advertised size, since tape manufacturers often don't measure very well...) If you remember who at Informix told you this, I'd be happy to set them straight :-} Maybe this should go in the FAQ. June ---- June Tong Informix Software ---- ---- Senior Consultant (415) 926-6140 ---- ---- International Support junet@informix.com ---- ---- Location-du-jour: Menlo Park ---- - - Please do not send me requests/questions by mail. When I have the knowledge - and time permits, I try to answer questions on comp.databases.informix, but - travel schedule, time, and volume make responding to personal requests - difficult and often slow. Please call your local Informix Technical Support - organization for assistance with technical issues.