Re: informix restore

Right. When you do a cold restore (of everything), then it will ask about log salvage (at least when it is finding the logs themselves, which depends on some internal information being available). This is sensible (or necessary), because with this kind of restore you are about to overwrite with the restore itself the dbspace on disk which possibly contains log files worth salvaging. So this salvage is the last opportunity to save that log data before overwriting it with the restore ... Warm restore can only be done for non-critical dbspaces. But since the dbspace(s) containing log files are critical, it is clear that a warm restore of a non-critical dbspace cannot overwrite log files on disk. Therefore log salvage is not strictly urgent for this operation, so ontape doesn't ask about it during a warm restore. Regards, Martin -- Martin Fuerderer IBM Informix Development Munich, Germany Information Management owner-informix-list@iiug.org wrote on 31.05.2005 16:34:53: > I saw it asking (pretty sure about it) to backup logical logs when > you do a full restore not just one dbspace. Or at least I cannot > remember asking for backing up logs when I did a dbspace restore > > On 5/30/05, Martin Fuerderer <MARTINFU@de.ibm.com> wrote: > > Hi, > > > > my testing with 9.40.UC6 did not exhibit this behaviour, i.e. > > it did not ask for log salvage. > > > > Instead it simply stops after physical restore of the down dbspace, > > because I had to say "n" when it asked for logs to restore as I > > had not backed them up yet. Also, saying "y", but not providing > > backed up logs only did abort the logical recovery. I.e. it did not > > take the logs from disk (even though they are there). > > > > You can do this logical restore in a second step, but before that > > you have to do "ontape -a" to first backup the logs. > > Then you can do "ontape -l" to restore them and get the dbspace > > to recover logically. After this it should be on-line. > > > > With that, you can do the "ontape -a" before starting the warm > > restore of the dbspace. Then you have them backed up already > > and you can say "y" when the restore asks for log tapes to > > restore. With that it will do the full recovery of the dbspace in > > one go. > > > > Using the last nightly logs (in your case), i.e. those that have been > > backed up together with the archive, will not really help. This is > > because they were actually filled the day before, but that "data" > > is already contained in the (physical) archive of the dbspace itself. > > > > During the restore you may still need the last log from nightly log > > backup, depending on whether you did the archive first and then > > the log backup or the other way round. (That means in general you > > may have to restore the log that was the current log at time of the > > archive operation.) So don't be too quick with removing "old" log > > backups. > > > > I would keep the backups of the logs for the whole week at least. > > That way you have a choice when restoring. You always need a > > level-0 archive for restore. But then you can either rely on any of > > the level-1 archives you did after the level-0 and use backed up > > logs to get current, or use only backed up logs (without any > > level-1 archive). > > > > I hope this helps, > > Martin > > -- > > Martin Fuerderer > > IBM Informix Development Munich, Germany > > Information Management > > > > owner-informix-list@iiug.org wrote on 30.05.2005 00:07:03: > > > > > > It will read the entries from disk only if you back them up... > > > > > > When you do the restore with ontape -r you are > > > prompted :- > > > > > > Do you want to back up the logs? (y/n) > > > > > > This then salvages the logs from on disk and puts them on tape. > > > i.e. performs a 'log salvage'. > > > > > > Note you MUST put in a fresh tape for this backup. > > > > > > Check the manual at > > > http://publib.boulder.ibm.com/infocenter/ids9help/index.jsp > > > > > > owner-informix-list@iiug.org wrote on 27.05.2005 21:22:22: > > > I did a cold restore and worked as a charm. > > > > > > Thank you so much. > > > > > > When I restore just a dbspace you are saying that I need to restore > > > the logical logs as well. > > > One more question: > > > Let say that the last backup ontape -s and ontape -a was done last > > > night at midnight. Now I need to restore just a dbspace that is having > > > problems. Where can I find the latest logs ? > > > Do I need to do a ontape -a before I do the partial restore ? > > > Using the last night's logs wouldn't help in this case right ? I > > > actually believe that they cannot be used at all in this case, right ? > > > > > > Thanks a lot > > > > > > On 5/27/05, Martin Fuerderer <MARTINFU@de.ibm.com> wrote: > > > > Hi, > > > > > > > > if I understood you correctly, then you did a so called "warm restore" > > > > of this one dbspace ? I.e. the database server was still running with > > > > all other dbspaces being OK ? > > > > In that case you have to restore logical logs. The logical logs need > > > > to be applied to this one restored dbspace to "let it catch up" with > > > > the rest of the system, so that the whole system will be consistent > > > > again. > > > > Without logical log restore, the dbspace (only physically restored) > > > > has the state of the time when the backup was done. But since the > > > > system has moved on in the meantime (i.e. some work was done > > > > in the other dbspaces), this physiaclly restored dbspace is not in > > > > sync with the rest. Logical restore is needed to get it there. > > > > > > > > If you do not have logical logs backed up, then you are at a loss at > > > > this point. In this case all you can do is restore the complete system > > > > (i.e. a cold restore), so that everything gets to the same state and > > > > thus will be in sync. Of course that means you will loose the work > > > > done since the last backup (level-0 or level-1) that is restored. > > > > If you want to recover such work also, you need to backup and keep > > > > logical logs so that you can restore them ... > > > > > > > > The zipping and unzipping that you did with the backup sounds > > > > about right. This should not be the problem. > > > > > > > > Regards, > > > > Martin > > > > -- > > > > Martin Fuerderer > > > > IBM Informix Development Munich, Germany > > > > Information Management > > > > > > > > owner-informix-list@iiug.org wrote on 26.05.2005 19:33:22: > > > > > onstat -d shows ) free space> > > > > > > > > > On 5/26/05, Gentian Hila <genti.tech@gmail.com> wrote: > > > > > > I run a backup ontape -s which was saved to a file and then zipped > > it > > > > > > through gzip and then unzipped it and restored through: > > > > > > > > > > > > ontape -r -D dbsdata> > > > > > > > > > > > but I didn't restore any logical logs ? Should I have restored > > them. > > > > > > > > > > > > Now dbsdata shows as Disabled in