Re: Restoring database using logs

In <X-Informix-List-Id: <news.1505> > Mark Herbert describes a disaster: > > We have Informix on an HP-UX 8.0 system. After rebooting the system > we tried to bring Informix back on-line and got an error message > indicating a corrupt database. We restored the raw device from the > last backup, and then started playing the log files back to bring the > database up to date. However, it stopped when it hit an error in the > log file. Apparently, several days ago we had a write error and a > message was written to the message log which we failed to see. The > applications using the databse have been working fine, but now we > cannot restore the database because of the error. Informix here says > they can't help, that there is nothing we can do. > > I find it hard to believe that the applications worked for the last week > but now Informix says it is all lost. > > Can someone verify that indeed it is not possible to get the information > in the log files back when an error in the database has occurred? If > it is possible, can someone give us some advise on what to do? > > Thanks for the help, > > - Mark - > ------------------------------------------------------------------------- > Mark Herbert > InterNet: mrh@guug.de > Mueller-BBM GmbH, Planegg b. Muenchen, Germany > Hello Mark, The best response I can give you is to suggest that you 'phone Informix Customer Service in Menlo Park. Assuming that your system will permit it, they can dial your system up and then reproduce your logs up to the point of the recorded write failure. The problem is that the backup will only be good up to the point in time of the problem being detected in the log. At issue is the question of how much this will save you. If the logs can be edited, and no data integrity problems are found, then it might be possible for the log file to be edited and permit more of the log to be entered into the database. Only you can answer that one. It appears that the log's problem is that the hardware found a problem that remained undetected by the application(s) that was running. It also seems that the system log files weren't being inspected as clarefully as they might have been, as running a Level 0 backup at the point of the failure might well have prevented this from occuring. I'm indebted to David Coburn of Informix, Inc, for technical assistance on this topic. I hope that this helps...let me know if I can do anything further. Cheers, Roger D. Parks Data/Database Admin ________________________________________________________________________ Roger D. Parks, Sc.D. 'A night without a day; a day without a night...' rogerp@amgen.com (or) uunet!amgen!rogerp vox: 800-9-AMGEN-9 ext 4584 Amgen might rent the mind and body, but all opinions are the owner's...