Re: [Zope] ZODB data loss - help required
On Don, 2013-12-05 at 15:42 +1000, Tom Cameron wrote: Questions My main aim is to work out what happened. My best guess is that Zope was somehow connecting to a stale or outdated file pointer and updating that file all along while the Data.fs was pointing to an August 5 copy. But how could this situation eventuate and persist for so long? for my, it looks exactly like that Zope used an inode, which wasn't the Data.fs you expected. It used that as long as you restarted Zope. your backups were always copying the old Data.fs from the filesystem path, where you expected the correct one to be in. that happens, when the directory with your Data.fs is moved (e.g. $ mv ./var ./var-bak) and a new one copied back to the old place (e.g. $ cp -R ./var-bak ./var). that happens also, when the Data.fs is deleted. there are chances, that the correct Data.fs is still somewhere around (except when it was deleted, then a data recovery service might be able to help). just a wild guess: did your backup script screw this up? best, johannes The odd thing is that we had 2 very similar incidents on 2 different Zope servers a few months ago but both resulted in almost no data loss as the timeframes were shorter and I dismissed them as some odd user error. We have recently moved most of our Zope servers to Linode - could it be their file system? or could it be the new way we setup the buildouts and init scripts? Any clues at all would be welcomed. -- Tom Cameron Technical Director Mooball IT ___ Zope maillist - Zope@zope.org https://mail.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - https://mail.zope.org/mailman/listinfo/zope-announce https://mail.zope.org/mailman/listinfo/zope-dev ) ___ Zope maillist - Zope@zope.org https://mail.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - https://mail.zope.org/mailman/listinfo/zope-announce https://mail.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] ZODB data loss - help required
Le 05/12/2013 09:43, Johannes Raggam a écrit : On Don, 2013-12-05 at 15:42 +1000, Tom Cameron wrote: Questions My main aim is to work out what happened. My best guess is that Zope was somehow connecting to a stale or outdated file pointer and updating that file all along while the Data.fs was pointing to an August 5 copy. But how could this situation eventuate and persist for so long? for my, it looks exactly like that Zope used an inode, which wasn't the Data.fs you expected. It used that as long as you restarted Zope. your backups were always copying the old Data.fs from the filesystem path, where you expected the correct one to be in. that happens, when the directory with your Data.fs is moved (e.g. $ mv ./var ./var-bak) and a new one copied back to the old place (e.g. $ cp -R ./var-bak ./var). that happens also, when the Data.fs is deleted. I'm agree with this description. You can test this python behavior in a python shell: when a file is unlinked in the filesystem (move or deleted) python move the file descriptor into RAM and still use it there without warning. The file descriptor is destroyed when the python process end (Zope stop or restart). Your only way is to find a Data.fs.old from the last pack somewhere or to have a backup. -- Encolpe DEGOUTE http://encolpe.degoute.free.fr/ Logiciels libres, hockey sur glace et autres activités cérébrales ___ Zope maillist - Zope@zope.org https://mail.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - https://mail.zope.org/mailman/listinfo/zope-announce https://mail.zope.org/mailman/listinfo/zope-dev )
Re: [Zope] ZODB data loss - help required
Tom Cameron t...@mooball.net schrieb: Ive just had a very disturbing and odd experience with data loss in the Hi Tom, do you have any Zope / event.log Logs from the timeframe? Just an idea: Did you make the Zope restart BEFORE your system update/-grade (i assume that you mean the Cent OS packet manager yum)? Did you make shure that all of your Zopes python libs (not managed by your yum system - if you have some) got rebuild after the system upgrade - at least the ones with system library / binary context? 5th September sounds a relative large timeframe today, but is possibly not if there was not a lot of changes / operations to ZODB or the volume was small. best regards, Niels. -- Niels Dettenbach Syndicat ITInternet http://www.syndicat.com ___ Zope maillist - Zope@zope.org https://mail.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - https://mail.zope.org/mailman/listinfo/zope-announce https://mail.zope.org/mailman/listinfo/zope-dev )
