[ClusterLabs] One volume is trimmable but the other is not?

[Klaus Wenninger]

On 01/26/2018 07:45 PM, Eric Robinson wrote:
>>> I sent this to the drbd list too, but it’s possible that someone here
>>> may know.
>>>
>>>
>>>
>>> This is a WEIRD one.
>>>
>>>
>>>
>>> Why would one drbd volume be trimmable and the other one not?
>>>
>> iirc drbd stores some of the config in the meta-data as well - like e.g. some
>> block-size I remember in particular - and that doesn't just depend on the
>> content of the current config-files but as well on the history (like already
>> connected and to whom).
>> Don't know if that helps in particular - just saying taking a look at differences
>> on the replication-partners might be worth while.
>>
>> I know that it shows the maximum discard block-size 0 on one of the drbds
>> but that might be a configuration passed down by the lvm layer as well.
>> (provisioning_mode?) So searching for differences in the volume-groups or
>> volumes might make sense as well.
>>
>> Regards,
>> Klaus
> Thanks for your reply, Klaus. However, I don't think it's possible that anything could be getting "passed down" from LVM because the drbd devices are built directly on top of the raid arrays, with no LVM layer between...
That is why I had written "passed down" as there is LVM on top of drbd and
not between raid and drbd ;-)

>
> {
>         on ha11a {
>                 device /dev/drbd1;
>                 disk /dev/md3;
>                 address 198.51.100.65:7789;
>                 meta-disk internal;
>         }
>
>         on ha11b {
>                 device /dev/drbd1;
>                 disk /dev/md3;
>                 address 198.51.100.66:7789;
>         meta-disk internal;
>         }
> }
>
> --Eric