[DRBD-user] Enabling two primaries break connection

Thomas Thrainer thomasth at google.com
Fri May 3 15:14:06 CEST 2013

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


Hi,

I just re-tested using Wheezy (Linux 3.2.0-4-amd64 #1 SMP Debian 3.2.41-2
x86_64 GNU/Linux) and DRBD 8.4.3.
I couldn't reproduce the original bug (having one side writing, and
toggling the other side between secondary/primary). However, if I try to
write on the "toggling" side to the disk when in primary mode, I could
still produce ProtocolError's.
As that's (fortunately) not required by Ganeti, we'll can probably ignore
this (although I will test some more of our use-cases with DRBD 8.4.3).

Can somebody confirm that the original behavior was a bug in DRBD 8.4.2
which was fixed in DRBD 8.4.3? Or could interactions with the kernel be the
problem?

Thanks,
Thomas


On Fri, May 3, 2013 at 2:56 PM, Louis <mailtolouis2020-forum at yahoo.com>wrote:

>
>
> Linux intel1 3.5.0-23-generic #35~precise1-Ubuntu SMP
>
>
>   ------------------------------
>  *From:* Luca Fornasari <luca.fornasari at gmail.com>
> *To:* DRBD <drbd-user at lists.linbit.com>
> *Sent:* Friday, May 3, 2013 1:01 PM
>
> *Subject:* Re: [DRBD-user] Enabling two primaries break connection
>
> Hi Louis,
>
> What kernel are yuo running?
>
> Cheers,
> Luca
>
>
> On Fri, May 3, 2013 at 1:41 PM, Louis <mailtolouis2020-forum at yahoo.com>wrote:
>
> Hi Thomas,
>
> I just tested your scenario on DRBD 8.4.3.  It seems fine, connection did
> not break.
> While doing the DD, I did change primary / secondary on bob node few
> times, but the  connection never break.
>
> The only thing I couldn't run this drbdadm --allow-two-primaries=yes
> <resource>, it give uknown command. But I do have allow-two-primaries setup
> in my drbd.conf, not sure that make any different?
>
> Regards
> Louis
>
>   ------------------------------
>  *From:* Thomas Thrainer <thomasth at google.com>
> *To:* Luca Fornasari <luca.fornasari at gmail.com>
> *Cc:* drbd-user at lists.linbit.com
> *Sent:* Friday, May 3, 2013 10:00 AM
> *Subject:* Re: [DRBD-user] Enabling two primaries break connection
>
> Hi,
>
> Given the fact that I could reproduce the bug regularly, I'm pretty sure
> that this is indeed a DRBD bug. Unfortunately I didn't find a bugtracker on
> the DRBD site. Is there one? If not, what's the official way to report bugs?
>
> For the record, here are the steps to reproduce:
>  * create a device with primary on alice and secondary on bob
>  * on alice: while true; do dd if=/dev/zero of=/dev/drbd0; done
>  * on bob: drbdadm --allow-two-primaries=yes <resource>; drbdadm primary
> <resource>
>  * you might have to drbdadm secondary <resource> on bob and then repeat
> the previous step in order to produce the bug
>
> Log files are as mentioned in the first mail of the thread.
>
> Cheers,
> Thomas
>
>
>
> On Tue, Apr 30, 2013 at 2:25 PM, Thomas Thrainer <thomasth at google.com>wrote:
>
> Hi Luca,
>
> I just reproduced the exact same problem using only drbdadm. I also
> inspected the output of the -d option, and drbdadm does the exact same
> thing as Ganeti in this regard.
>
> Thanks,
> Thomas
>
>
> On Tue, Apr 30, 2013 at 2:18 PM, Thomas Thrainer <thomasth at google.com>wrote:
>
> Hi Luca,
>
> I'll try the drbdadm method this as soon as I get to it. Right now I have
> no machines around which are already configured via drbdadm.
>
> Note that I have included both logs (secondary and primary) in my first
> email.
>
> I use DRBD 8.4.2 because 8.4.3 didn't compile against my kernel (3.2.27)
> and I didn't want to put much work into it. I this bug is known and fixed
> in 8.4.3, I'll might look into compiling against 3.2.27 again.
>
> Cheers,
> Thomas
>
> --
> Thomas Thrainer | Software Engineer | thomasth at google.com |
>
>  Google Germany GmbH
> Dienerstr. 12
> 80331 München
>
> Registergericht und -nummer: Hamburg, HRB 86891
> Sitz der Gesellschaft: Hamburg
> Geschäftsführer: Graham Law, Katherine Stephens
>
>
>
>
> --
> Thomas Thrainer | Software Engineer | thomasth at google.com |
>
>  Google Germany GmbH
> Dienerstr. 12
> 80331 München
>
> Registergericht und -nummer: Hamburg, HRB 86891
> Sitz der Gesellschaft: Hamburg
> Geschäftsführer: Graham Law, Katherine Stephens
>
>
>
>
> --
> Thomas Thrainer | Software Engineer | thomasth at google.com |
>
>  Google Germany GmbH
> Dienerstr. 12
> 80331 München
>
> Registergericht und -nummer: Hamburg, HRB 86891
> Sitz der Gesellschaft: Hamburg
> Geschäftsführer: Graham Law, Katherine Stephens
>
> _______________________________________________
> drbd-user mailing list
> drbd-user at lists.linbit.com
> http://lists.linbit.com/mailman/listinfo/drbd-user
>
>
>
> _______________________________________________
> drbd-user mailing list
> drbd-user at lists.linbit.com
> http://lists.linbit.com/mailman/listinfo/drbd-user
>
>
>
> _______________________________________________
> drbd-user mailing list
> drbd-user at lists.linbit.com
> http://lists.linbit.com/mailman/listinfo/drbd-user
>
>
>
> _______________________________________________
> drbd-user mailing list
> drbd-user at lists.linbit.com
> http://lists.linbit.com/mailman/listinfo/drbd-user
>
>


-- 
Thomas Thrainer | Software Engineer | thomasth at google.com |

Google Germany GmbH
Dienerstr. 12
80331 München

Registergericht und -nummer: Hamburg, HRB 86891
Sitz der Gesellschaft: Hamburg
Geschäftsführer: Graham Law, Katherine Stephens
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.linbit.com/pipermail/drbd-user/attachments/20130503/d570b40f/attachment.htm>


More information about the drbd-user mailing list