[DRBD-user] Switching from internal to external meta-disk

Felix Frank ff at mpexnet.de
Wed Jul 11 09:32:45 CEST 2012

Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.


On 07/10/2012 06:59 PM, Jean-Baptiste wrote:
>  9. Doing drbdadm -- --overwrite-data-of-peer primary <RES> (from the
>     primary node)
> 10. Let synchronize process ending
> 11. Done
> At this step everything is fine, my SGBD was restarted without any
> warning, nothing seems to go wrong.
> But ... I was lost 11 days of data in my SGBD.

we've seen similar effects on several occasions on this list. So far, it
has always (iirc) been a case of "diskless primary".

Have you retained logs from 11 days ago? I'd expect you to find a note
around that time stating that your primary detached its backing device.

*If* this assumption is correct, here's what's happened then: You
primary happily kept writing data, but it never reached its local HDD.
Instead, all changes were written to the secondary's disk only. When you
did your changes and overwrote the data of the secondary, you killed
your data.

Bottom line is, it's crucial to be mindful of the health state of your
resources. Ideally, monitoring should report whenever your disks are not
UpToDate/UpToDate, among other possible problems.


More information about the drbd-user mailing list