Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On 16/08/2016 07:09, Craig Thompson wrote:
> Basic DRBD link not syncing
>
> First post to the list. I've tried using search engines to find this
> info but haven't so far.
>
>
> I have two servers. They each run Xen hypervisor to support guest
> virtual machines. They each have multiple LVMs for the underlying
> disk images of the virtual machines.
>
> I have set up Machine A to be the Primary for Guest1. Machine B is
> the Secondary for Guest1.
>
>
> The config I have for each looks like this:
>
>
> resource guest1 {
> net { protocol C; }
> device /dev/drbd3;
> disk /dev/vg0/guest3;
> meta-disk internal;
> syncer { verify-alg "md5" ; }
>
> on primary.host.domain {
> address 192.168.1.10:7789;
> }
>
> on secondary.host.domain {
> address 192.168.1.20:7789;
> }
> }
>
>
> I can use drbdadm and bring the resources up. I can force a primary.
> This initiates a full sync the first time.
>
>
> However, if I emulate an outage on Machine B (secondary) for minutes
> or hours and then bring it back online, the syncing doesn't continue
> automatically.
>
>
> I don't know what I'm missing in configuration(s). I may be missing
> something in the overall picture. But what I WANT to have happen is
> that DRBD sees when the link is down, pauses and then picks up syncing
> after an outage on the remote end.
>
>
> If I run a 'drbdadm verify guest1', then it will initiate a review,
> sync the out of sync blocks and then say it's up to date.
>
>
> But if I go to the Machine A and create a new file on guest1, then
> shut down guest1 so that no other changes are made, and then I go to
> Machine B and bring guest1 up, the newly created file is NOT there.
>
>
> So, I'm missing some key component that KEEPS things syncing after the
> initial sync is completed.
>
>
> Help? Documentation pointers? FAQs? How-Tos?
>
>
> Thanks in advance.
>
>
There was a similar question on the list just a few days ago, not sure
if that was you.
In any case, the best thing to check/verify is that your VM is accessing
/dev/drbd3 and that nothing (except DRBD itself) is accessing
/dev/vg0/guest3 (on both primary and secondary).
Any changes made to /dev/vg0/guest3 are unknown to DRBD, and so DRBD
will not know that they should be synced to the other node. It is the
same as creating a MD array with /dev/sda1 and /dev/sdb1 as /dev/md1 and
then writing to /dev/sda1 and complaining there is not consistent data
on /dev/sdb1.
I hope that helps, if not, please see if you can include a step by step
process, with all commands you entered, all output generated from each
step, which will show the problem.
Regards,
Adam
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20160817/eb157187/attachment.htm>