[Linux-cluster] Re: About CS global shutdown

[Alain Moulle]

Alain Moulle wrote:


>>>> Hi
>>>>
>>>> I wonder what is the best way to stop safely the CS 4 on a big amount
>>>> HA pairs, from a management node,  with the idea to shutdown
>>>> all nodes after that :
>>>>
>>>> Is it better to use :
>>>> 1/
>>>> pdsh "clusvcadm -l" launched on all nodes
>>>> then
>>>> pdsh "clushutdown" launched on all nodes
>>>> then
>>>> proceed to poweroff on all nodes.
>>>>
>>>> or
>>>> 2/
>>>> pdsh "service rgmanager stop" launched on all nodes
>>>> pdsh "service fenced stop" launched on all nodes
>>>> pdsh "service cman stop" launched on all nodes
>>>> pdsh "service ccsd stop" launched on all nodes
>>>>
>>>> I think that 1/ is more safe, because in 2/ some applications
>>>> could begin to failover just before the 2nd node of a pair
>>>> receives at its turn the stop commands .
>>>> The 1/ avoids any attempt to failover for nothing.
>>>>
>>>> Am I right ?
>>>> Thanks
>>>> Alain
>>>>


>> Hi Alain,

>> I'm kind of new to this (so I could be wrong), but here are my beliefs:

>> Option 1 only takes care of stopping the rgmanager services running on the
>> cluster.  (Besides, clushutdown already does a clusvcadm -l for you).  It
>> really doesn't inform the rest of the cluster the intent of the node
>> going down.

>> Option 2 shouldn't really be necessary, because reboot or halt should
>> execute the proper service shutdowns in the proper order.  However, it
>> also doesn't inform the rest of the cluster the intent of the node going
>> down.

>> You want to inform the rest of the cluster that they're going down,
>> otherwise
>> some of the nodes may start trying to fence the other nodes going down, etc.
>> Perhaps you should consider something like:

>> pdsh "clushutdown" launched on all nodes
>> pdsh "cman_tool leave remove" launched on all nodes
>> pdsh "shutdown" or "halt" launched on all nodes

>> Regards,

>> Bob Peterson
>> Red Hat Cluster Suite

Hi Bob
Thanks for you clarification . Nethertheless, several questions :

1/It seems that clushutdown is not packaged in the CS4 update 2 rpms whereas
the man is in package ...  is it missing for a special reason ?

2/ what does cman_tool leave remove does exactly ?
and would it be a workaround for the remaining problem about
"service cman stop" which fails 1 time for 5 (and in this case
lsmod lists a remaining user of the module, but without its name)

Regards
Alain Moullé