Am 30.10.2008 14:27 Uhr schrieb "Lars Marowsky-Bree" unter <[EMAIL PROTECTED]>:

> On 2008-10-30T12:40:43, Annette Jäkel <[EMAIL PROTECTED]> wrote:
> 
>> But my problem is that specific order of the nfsserver resource after all
>> filesystem resources. This works fine until one of the file system crashes.
>> Then nfsserver stops and the whole system doesnt work. Thats not what I
>> want. If a file system crashes, for example because physical device was
>> broken, the remaining devices and file systems should work and exported to
>> clients. So maybe the nfsserver should start without any order? But I'm not
>> shure that this is a good idea. I also dont want to run NFS, if there is no
>> device it can manage.
> 
> Ah, OK, so the interleaving is not your highest priority.
> 
> I think rsc_order/_colocation constraints with score=0 achieve exactly
> what you need.

I think, I have to learn more about individual scores. Until now I use
heartbeats default scores, never set a score manually. Meanwhile I read the
linux-HA score basics docs. I understand your proposal this way: score=0
mean, that nothing occurs because no score is changed. So if a filesystem
resource fails, nfsserver resource should still run. Thats fine. But whats
with the starting order of the resources? Does this occur in the right order
if score of order=0? And what with the condition, that mounted filesystems
and nfsserver MUST run on the same node? Does'nt this mean that colocation
score should be INFINITY?

BTW: All order constraints in my current cib.xml are written without a
score. Regarding to score documentation score then defaults to 0. All
colocation constraints defaults to INFINITY.

I will test the case on a testcluster with explicit setting of score=0.

> 
>> Meanwhile I read within Michael Schwartzkopff's Linux-HA book. He presented
>> an example NFS service with DRBD devices and if I understand all setup steps
>> right, there is really no order from any resource to nfsserver. I dont
>> understand this.
> 
> That would be wrong.
> 
>> Within this context I think about setting up a group of all filesystem
>> resources, setting attribute "ordered" to "false" and define a single
>> resource of nfsserver ordered after the group - but dont wait for the
>> complete start of the group, but starts if any resource of the group is
>> running.
> 
> Well, that is the interleave part, which is not necessarily required for
> correctness, but for speeding up the start. That is not currently
> possible.
> 
> I'm also not sure if it is indeed what you want; you want to have tried
> starting everything before bringing online "nfsserver", I think, so that
> they are all present to be exported - but not not start nfsserver if
> just one of them has failed to start.
>

Think you're right. But does'nt this sounds like a scenario for a
on_fail=ignore|block for the start and monitor operation of every filesystem
resource?
Regards,
Annette

>> In another thread (HA-NFS strategic question) Xinwei Hu suggested not to
>> manage nfs but the step of exporting the devices, but seems theres no RA for
>> this specific task. Until now I write /etc/exports by hand and call
>> "exportfs -a" from outside heartbeat, if I add or delete a filesystem.
> 
> Yes, this is currently missing I think. Even Xinwei's nfsserver RA is
> "global" and doesn't support managing individual exports. It would be
> great if this was added.
> 
> 
> Regards,
>     Lars


_______________________________________________
Linux-HA mailing list
[email protected]
http://lists.linux-ha.org/mailman/listinfo/linux-ha
See also: http://linux-ha.org/ReportingProblems

Reply via email to