[Ocfs2-users] bug resolve yet for export OCFS2 volume to NFS client ?

[Sérgio Surkamp]

Yes. The OCFS2 mount point become unaccessible if the bug
occur and the hanged OCFS2 node need to be rebooted to make it
available again. The other OCFS2 nodes will block until the hanged node
timeout or reboot, resuming normal operation after it. Any attempt to
read or write will block the attempting process in D state.

So disabling the READDIRPLUS on NFS clients is the safest option to
export the OCFS2 volume and avoid/workaround the bug.

Regards,
Sérgio

Em Wed, 23 Mar 2011 00:47:29 +0800 (GMT+08:00)
Thomas Lau <thomaslau at esun.com> escreveu:

> so READDIRPLUS will deadlock ocfs2 itself ?!
> 
> ----- Original Message -----
> From: "Sérgio Surkamp" <sergio at gruposinternet.com.br>
> To: "Thomas Lau" <thomaslau at esun.com>
> Sent: Wednesday, March 23, 2011 12:37:55 AM
> Subject: Re: [Ocfs2-users] bug resolve yet for export OCFS2 volume to
> NFS client ?
> 
> NFS READDIRPLUS bug:
> http://oss.oracle.com/bugzilla/show_bug.cgi?id=977
> 
> Fragmentation bug:
> http://oss.oracle.com/bugzilla/show_bug.cgi?id=1189
> 
> Regards,
> Sérgio
> 
> Em Tue, 22 Mar 2011 23:34:14 +0800 (GMT+08:00)
> Thomas Lau <thomaslau at esun.com> escreveu:
> 
> > 
> > what is exactly the bug is ?!
> > 
> > 
> > ----- Original Message -----
> > From: "Sérgio Surkamp" <sergio at gruposinternet.com.br>
> > To: ocfs2-users at oss.oracle.com
> > Sent: Tuesday, March 22, 2011 11:12:59 PM
> > Subject: Re: [Ocfs2-users] bug resolve yet for export OCFS2 volume
> > to NFS client ?
> > 
> > Hi,
> > 
> > Our NFS setup is running stable since we have disabled READDIRPLUS
> > on our FreeBSD clients. The OCFS2 cluster servers are with about
> > 200 days of uptime now and last reboot was to upgrade the kernel
> > version.
> > 
> > As a general recommendation, I suggest you to use the Oracle's
> > Unbreakable Linux kernel on top of CentOS 5.4 (or RedHat EL 5.4) and
> > OCFS2 1.6, also provided by Oracle, to avoid the known fragmentation
> > bug and to be able to enable the indexed directories feature for
> > improved performance.
> > 
> > If you are using only Linux NFS clients, you can try running with
> > READDIRPLUS enabled, but maybe you experience the same bug as
> > FreeBSD NFS client and disabling the READDIRPLUS call is the only
> > known way to avoid the problem.
> > 
> > To install the Unbreakable, fallow the instructions provided by
> > Oracle on its yum repository:
> > 
> > http://public-yum.oracle.com/
> > 
> > Regards,
> > Sérgio
> > 
> > Em Tue, 22 Mar 2011 14:52:11 +0800
> > Thomas Lau <thomaslau at esun.com> escreveu:
> > 
> > > I found this from ocfs1.4 document:
> > > g) NFS
> > > OCFS2 volumes can be exported as NFS volumes. This support is
> > > limited to NFS version 3, which translates to Linux kernel version
> > > 2.4 or later. Users must mount the NFS volumes on the clients
> > > using the nordirplus mount option. This disables the READDIRPLUS
> > > RPC call to workaround a bug in NFSD, detailed in the following
> > > link:
> > > http://oss.oracle.com/pipermail/ocfs2-announce/2008-June/000025.html
> > > Users running NFS version 2 can export the volume after having
> > > disabled subtree checking (mount option no_subtree_check). Be
> > > warned, disabling the check has security implications (documented
> > > in the exports(5) man page) that users must evaluate on their own.
> > > 
> > > is it being fixed with centos 5.3 (2.6.18-164.11.1.el5)?
> > > 
> > > anything I need to aware for exporting OCFS2 volume via NFS?
> > > 
> > 
> > 
> > 
> 
> 
> 



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