Hi Arno, Do you have some pointers on how I can investigate that? In my previous setup, I had my luks device directly on top of my iscsi device. That worked great in the beginning, but after a power failure on the iscsi server, my volume was destroyed. Since the luks device was the only contents on the iscsi device, there was not much testing/investigating that I could do. So I changed the setup: I created an LVM volume on my iscsi device, and the luks device inside the LVM volume. That way, I thought, I would at least know what part of the setup caused the malfunction. I mean, if the iscsi device itself would become corrupted, I wouldn't be able to activate the LVM volume anymore, but if dm-crypt were to make some mistake, I would expect to still be able to activate the LVM volume, but then not be able to read the luks volume. Right? Well, it turns out I can still activate the LVM volume just fine, so apparently there are no media errors / overwritten headers, at least no overwritten LVM headers. But then, after I activated the LVM volume, dm-crypt can't read the luks volume. So apparently -only- the luks volume is damaged in some way. So... how can I investigate this further? Kind regards, Erik. On 03/04/2013 03:04 PM, Arno Wagner wrote: > Hi Erik, > > first, you can make a header-backup, see the FAQ. Second, you can > investigate what destroys the header. The same thing could > well destroy a filesystem, RAID-superblock, etc. > Or put differently: Something is very, very wrong in > your set-up. Loss of the LUKS header can only happen if > einther the user does it (directly or indirectly) or > somethign is broken. > > Arno > > On Mon, Mar 04, 2013 at 01:58:31PM +0100, Erik Logtenberg wrote: >> Hi all, >> >> I've been using dm-crypt for quite some years now, and every now and >> then I am very unpleasantly surprised by the message that my entire >> volume can no longer be read: >> >> Device /dev/disk/by-path/ip-foo.bar:mainstorage-lun-1 is not a valid >> LUKS device. >> >> In this case the iscsi server was rebooted while the volume was still >> mounted. The volume is used for making backups and no backups were >> currently made, so no actual writes got lost. Nevertheless after reboot >> it no longer recognizes my luks volume. >> >> I've had this kind of malice before and at that time was unable to fix >> it. So in the end I gave up, created a new luks volume and started from >> scratch. >> >> However I hope that is not how every future power failure is going to >> end up. Is there anything I can do to fix this volume or anything I can >> do to prevent such a simple event from causing such catastrophic results? >> >> Kind regards, >> >> Erik. >> _______________________________________________ >> dm-crypt mailing list >> dm-crypt@xxxxxxxx >> http://www.saout.de/mailman/listinfo/dm-crypt > _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx http://www.saout.de/mailman/listinfo/dm-crypt
