Re: mirrored chunks

Hi Stephanie, First, I'd call Informix Tech. Support. If appropriate, them you have a 'Production System Down'. This will escallate your case within the Tech. Support organization to get immediate attention. Your mirroring should switch over upon error on the primary chunk. There is not manual intervention required (which would kind of defeat the purpose of mirroring IMHO). I have some fundamental questions for you. Were the primary and mirror chunks on different physical disks? They should be. Were they on separate controllers/channels? Separate would be preferable. If you answered 'yes' to the first question it's possible the system shutdown more than one drive after a disk error was experienced. I've seen this happen before on some systems. You may also want to look to see if a connection to an external drive was disturbed or if the drive(s) were physically shocked. What is the state of your OnLine instance? Are you still online? You may want to try to perform a backup on a new tape (don't overwrite an existing backup tape in case you need it). Check your online log file (specified by the MSGPATH parameter in the TBCONFIG file) for messages which may give you some add'l information. If your OnLine instance is running and you don't see any reason why the mirrored chunk would be marked down, try bringing it online via tbmonitor's Dbspaces/Status option (or via tbspaces -s at the command line). Regards, Bob Colombo CSE, Informix Boston # Std. disclaimers apply. In article <Cw6rHs.to@primenet.com> sco@jcm.com (Stephanie Valencia) writes: >Help please. > >We are running Online 5.02 for Interactive Unix. >All of our database chunks (we have 11) are mirrored. >Twice in the past four months, chunks have gone off line >and we have had to restore from tape. > >Why would the mirrored chunk not have been used instead? >When the chunk goes off line, is it supposed to take the mirrored >one with it? > >Is there something special needed to get the mirrored chunk to >be used when the regular one goes off line? > >-- >Stephanie Valencia >NTT >sco@mchr.nteltec.com