Re: Question on the Archive TAPEDEV size

This may be hardware specific -- I am running HP-UX 10.20 with online 7.22 and have 4gig tape -- when running onarchive and went over the 2 gig amount the tape died (onconfig set at 4096000 -- yes - 4 Gig) -- gave no error and no prompt for another tape. I called Informix and they said that they do not support tape size greater than 2 gig -- the exact number they gave me was 2147483647 (Clifton -- case # 679169). I hope that the 2 GB limit for HP would be eliminated in the future -- and it is great that it does not seem to be a problem elsewhere. Have you ever restored from beyond the 2 GB mark to make sure it is really there? Nils Myklebust wrote: > > I have the tape size set to 4000000 which means 4 Gigabyte. > That works fine. > > It's claimed here in c.d.i. from time to time that the max size of the > tape drive is 2 GB. That is wrong. What do you think all the people > with DLT or other large tape drives do? > > See further comments below: > > Tom Grenier <tomg@biztravel.com> wrote: > > :Hi Suj, > :I'm not sure if I understand you question correctly, but INFORMIX will > :only recognize up to a 2 Gig tape size. We had our onconfig size set to > :4 Gig (what our tapes will handle using compression). When I went > :beyond 2 Gig the tape just stopped -- no prompt to enter new tape -- > :nothing. Only changing the onconfig parameter worked. > : > :I have the exact number Informix gave me at the office -- if you want it > :let me know (it is a little greater than 2000000K). I know of no > :problem stating a larger number than the capacity in the onconfig file > :-- but if you go over the 2 Gig mark (in onconfig) and you really feed > :more than 2 Gig to a tape you are in trouble. > : > :sujata_soman_at_omm-la2-infotech-001@internet.omm.com wrote: > :> > :> Hi everybody, > :> I have a unique problem. I am being forced to increase the size of my > :> TAPESIZE variable in the onconfig file to something greater than the actual > :> capacity of the TAPE, if I need my regular backup ( ontape -s ) to work fine. > :> Well, this restriction is being forced by some @#$@$ system administration tool > :> that is installed on top of UNIX. ( Don't look at me, the decision was not mine > :> to take, and besides, I was not here ). Anyway, this tool was working fine until > :> version 7.13, and last weekend we upgraded to 7.23, and we don't have a backup > :> since then! > > Does this tool then switch tape automatically when one is full? If it > can manage that in a way that is compatible with ontape you do in fact > have a "logical" tape drive of larger capacity than your fysical > drive. In this case it should work fine to set the tapesize to > anything. The fact that it doesn't work any more may be due to some > change in how ontape work that your tool doesn't handle properly. > > :> According to their support staff, we have to disable Informix from > :> detecting the end of tape, and let the tool do it. > > Well, ontape doesn't detect the end of tape. That is the problem with > ontape in this respect. (Informix claims there are problems with > detecting end of tape on some platforms. I suspect this to be a very > old problem that is now resolved on any reasonable platform, so they > should realy change ontape to work accordingly.) > You in effect have to tell ontape via the TAPESIZE parameter how much > data the tape is guaranteed to take BEFORE end of tape is reached. > When this much data is written ontape will simply ask for another tape > whether the current one is full or not. > If ontape ever reaches the end of the tape it will crash and you will > have no backup. > The only thing I can understand such a tool could do is to be some > kind of device driver for the tape that would detect the end of tape, > but then not report it back but instead switch automatically to > another tape either on another drive or via an autochanger. I think > the BMP tools (formerly ztools) are doing something like this. > > :> The question I have is as follows:- > :> Somewhere deep in this user group mail, I remember reading that if you > :> actually set the tapesize to more than the capacity of the tape, it might crash > :> the server. > :> My environment is IBM AIX 4.1.4, Informix ODS ver 7.123 UC1,and for anyone who > :> wants the name of the #$@#$ system administration tool, e-mail me !! > :> Anybody know anything about this ?? Will it cause serious problems if I do > :> this? > :> > :> ******************************************************************************** > :> ****************************** > :> * Sujata Soman > :> * > :> * E-Mail: ssoman@omm.com > :> * > :> * Database Administrator ( Informix ) > :> * > :> * O'Melveny & Myers, Los Angeles > :> * > :> ******************************************************************************** > :> ****************************** > : > :-- > :Tom Grenier ########################################################### > :# Home: Office: # > :# BizTravel.com # > :# The Internet company for frequent # > :# business travelers(sm.) # > :# Phone: (800) 497-1969 (617) 621-3919 x115 # > :# e-mail: tom@sqlman.com tomg@biztravel.com # > :# web page: http://www.sqlman.com http://www.biztravel.com # > :######################################################################## > > Nils.Myklebust@idg.no > NM Data AS, P.O.Box 9090 Gronland, N-0133 Oslo, Norway > My opinions are those of my company > The Informix FAQ is at http://www.iiug.org -- Tom Grenier, DBA Biztravel.com