[pve-devel] Default cache mode for VM hard drives

[Dietmar Maurer]

> > It is also quite curious that DRBD layer has checks that detect this
> > problem (but doesn't attempt to fix it).
> >
> 
> DRBD does not catch this by default but:
> - it detects checksum mismatch if data-integrity-alg is enabled
> (disabled by default and recommended to be disabled in production)
> - the issue can be discovered during drbdadm verify

I can see that it is bad if RAID devices contains different data (not
really acceptable for me). But in this case, it is due to wrong behavior 
inside the application, so the application cannot expect to read back
"correct" data. So my question is what errors/problems do you get with
those VMs? RAID data is inconsistent, but does those VMs show any errors
or problems?