nfs mount locally exported directories in a Red HAt Cluster (v3)?

[Rick Stevens]

evdhn at advalvas.be wrote:
>>>>>In a Red Hat HA Cluster (v3), how can you nfs mount a directory
>>>>>exported
>>>>>by a cluster service that is currently local to the cluster member?
>>>>>I keep getting permission denied errors.  It works fine when I move the
>>>>>cluster service to the other cluster member.  The firewall has been
>>>>>stoppped, just to make sure it wasn't part of the problem.
>>>>
>>>>Make sure you have portmapper and nfslock running on both the client and
>>>>server.  That's the most common problem.
>>>>----------------------------------------------------------------------
>>>>- Rick Stevens, Senior Systems Engineer     rstevens at vitalstream.com -
>>>>----------------------------------------------------------------------
>>>
>>>Thanks for your answer Rick, but apparently I explained poorly.
>>>
>>>This is a two-member cluster with hostnames arneb and nihal and services
>>>lepusbb and lepustl.
>>>When service lepusbb runs on arneb, I cannot nfs mount its device on
>>>arneb
>>>using the service name.  I.e.
>>># mount -t nfs lepusbb:/usr/local/lepus-bb /usr/local/bb
>>>does not work on arneb, but it does work on nihal.
>>>Similarly, I can mount lepustl:/usr/local/lepus-tl on arneb but not on
>>>nihal.
>>>
>>>I meanwhile found that
>>># mount -t nfs arneb:/usr/local/lepus-bb /usr/local/bb
>>>does work, so I'm currently using that as a workaround, but obviously,
>>>when a failover would occur while the devices are locally mounted, my
>>>scripts wil be in trouble.
>>>
>>>And yes, portmapper and nfslock are running:
>>># ps auxw | egrep -e lock -e portm | grep -v grep
>>>rpc       3109  0.0  0.0  1672  608 ?        S    10:36   0:00 portmap
>>>root      3314  0.0  0.0     0    0 ?        SW   10:36   0:00 [lockd]
>>>root      3453  0.0  0.0  3064 3064 ?        S<L  10:36   0:00
>>>/usr/sbin/clulockd
>>
>>First, are you sure the device is being exported by arneb and that arneb
>>is permitted to mount it?  A "showmount -e arneb" will show what's being
>>exported and who's allowed to look at it.
>>
>>I'm not familiar with RH's HA (high availability) structure so I can't
>>speak to the details, but generally it's something along those lines.
>>----------------------------------------------------------------------
>>- Rick Stevens, Senior Systems Engineer     rstevens at vitalstream.com -
>>----------------------------------------------------------------------
> 
> 
> It must be a RH HA thing then.
> 
> # showmount -e arneb
> Export list for arneb:
> /usr/local/lepus-bb                          arneb,nihal
> /usr/local/lepus-bb/server                   gienah,albireo,sair,ruchba
> /usr/local/lepus-bb/content                  gienah,albireo,sair,ruchba
> /usr/local/lepus-bb/sessions                 gienah,albireo,sair,ruchba
> /usr/local/lepus-bb/course_image_main_images gienah,albireo,sair,ruchba
> 
> Even when I specify that all nodes ("*") should have access, it still
> won't work. :-(

I'm not certain what HA means by "service", but generally, NFS mounts
specify the remote end as "nodename:/export", not as "service:/export".
Try:

	mount -t nfs arneb:/usr/local/lepus-bb /usr/local/bb

on nihal and see if that works.  It should.  Also make sure that the
server (arneb) is running nfsd.  The existance of an exports file should
trigger it.
----------------------------------------------------------------------
- Rick Stevens, Senior Systems Engineer     rstevens at vitalstream.com -
- VitalStream, Inc.                       http://www.vitalstream.com -
-                                                                    -
-      We are born naked, wet and hungry. Then things get worse.     -
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