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Trying to recover Secondary using ontape -l

Posted in 2003

Topics: High Availability & Replication, Backup & Restore, Logging & Checkpoints, Versions, Editions & End-of-Life

antzz — — source: Usenet: comp.databases.informix

I have an HDR setup (IDS 7.31 on SCO UNIX). As an experiment, I shutdown the Secondary for the weekend. I have logical log backups every hour on the Primary using a disk file. On the first workday, I restarted the Secondary and it went into Fast Recovery(Sec) mode. The message log prompted me to start recovery from tape (i.e. the logs have already cycled on the Primary). I redirected the first disk file backup to my LTAPEDEV device and started ontape -l. It stated that I have to roll forward using log number 21270 and prompted me to insert another tape? Now, I know that the disk file I have contains log number 21270. Why isn't ontape detecting this??? Is there a trick or special way to recover from disk files? -- Posted via http://dbforums.com

↪ replying to antzz
Jonathan Leffler — — source: Usenet: comp.databases.informix

antzz wrote: > I have an HDR setup (IDS 7.31 on SCO UNIX). As an experiment, I > shutdown the Secondary for the weekend. I have logical log backups > every hour on the Primary using a disk file. On the first workday, I > restarted the Secondary and it went into Fast Recovery(Sec) mode. The > message log prompted me to start recovery from tape (i.e. the logs have > already cycled on the Primary). I redirected the first disk file backup > to my LTAPEDEV device and started ontape -l. It stated that I have to > roll forward using log number 21270 and prompted me to insert another > tape? Now, I know that the disk file I have contains log number 21270. You've got that information in the records you keep, haven't you? > Why isn't ontape detecting this??? You have to be very careful - it doesn't expect the device name to change during recovery, IIRC. So, normally, you have two windows open. One runs the recovery using a symbolic link as the 'tape device'. The other is used to 'switch tapes' by repointing the symlink to the correct new log file each time the recovery asks for the next 'tape'. > Is there a trick or special way to recover from disk files? Yes; see above. Note that it is a good idea to practice these things - preferably moderately often and in a variety of states (level 0, level 1, level 2 backups, with and without extra log files), just to make sure you have the recovery process sorted out completely. -- Jonathan Leffler #include <disclaimer.h> Email: jleffler@earthlink.net, jleffler@us.ibm.com Guardian of DBD::Informix v2003.04 -- http://dbi.perl.org/

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