[Ocfs2-users] any way to ignore quorum in a two node cluster with one node down?

[Andrew D. Ball]

Given that the change is non-trivial, would requiring at least three
nodes to be in the ocfs2 be a successful workaround?

Thanks for your help,
Andrew

On Fri, 2007-07-20 at 10:10 -0700, Sunil Mushran wrote:
> There are dlm bug fixes that should already be in SLES10 SP1.
> 
> The change for what you are looking for was not trivial and
> merging it in the 1.2 tree will not be either.
> 
> Some of the patches related to this are as follows:
> 
> Date:   Fri Sep 8 11:37:32 2006 -0700
> 
> commit 3384f3df5ed939a25135e1b2734fb7cdee1720a8
> ocfs2: Allow binary names in the DLM
> 
> commit ea5b3a187e2724fa9d08b2fbd3898c149ed95c6b
> ocfs2: Update dlmfs for new dlmlock() API
> 
> commit f0681062b8e369d9fb6f3ce10f4e3fc8cea5f910
> ocfs2: Update dlmglue for new dlmlock() API
> 
> commit d680efe9d8fe0eb99d9dd063a4def6b362cdb40d
> ocfs2: Add new cluster lock type
> 
> commit 80c05846f604bab6d61e9732c262420ee9f5f358
> ocfs2: Add dentry tracking API
> 
> commit 379dfe9d0db99ed33fb089fcb9c07f5f92566e9e
> ocfs2: Hook rest of the file system into dentry locking API
> 
> commit 1390334b4c697b7588d5661fcf6acaeec409cf4c
> ocfs2: Remove the dentry vote
> 
> commit 1ba9da2ffa54b56a6346746248bfa38124d499a6
> ocfs2: manually d_move() during ocfs2_rename()
> 
> Needless to add, this changes the dlm protocol.
> 
> Andrew D. Ball wrote:
> > Can you help me determine which patches need to be backported to SLES 10
> > SP1 to resolve this?  Someone in the LTC saw the following that looked
> > promising:
> >
> > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=2f5bf1f2d061dea5146aa283685ce2b00cea2f3d
> >   
> > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=78062cb2e54ffe0df811dce5e68b54da9b8c9025
> >   
> > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=b36c3f84988eebf38acaccc756e05f6b70e333ab
> >   
> > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=3fca0894a4b5e52c278421b04435b88e32b423ad
> >   
> > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=0dd82141b236ce36253e3056c6068ee3d5732196
> >   
> > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=e4968476a9bc5a6b30076076b4f3ce3e692e0d79
> >   
> > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=f3f854648de64c4b6f13f6f13113bc9525c621e5
> >   
> >
> > Thanks!
> > Andrew
> >
> > On Tue, 2007-07-17 at 16:17 -0700, Sunil Mushran wrote:
> >   
> >> Ahh... this is a 1.2 "feature". :)
> >>
> >> In 1.2, the fs does messaging (votes) for mount/umount, rename,
> >> unlink and delete. So the said operations can fail... if a node dies
> >> during the voting process.
> >>
> >> We have addressed this issue in mainline. Sometime in 2.6.18/19.
> >> As in, rename, unlink and delete now use the dlm and thus should
> >> no longer fail on a node death.
> >>
> >> Andrew D. Ball wrote:
> >>     
> >>> >From /var/log/messages:
> >>>
> >>> Jul 16 17:06:43 enva11 kernel: (29933,2):ocfs2_broadcast_vote:725 ERROR:
> >>> status 
> >>> = -107
> >>> Jul 16 17:06:43 enva11 kernel: (29933,2):ocfs2_do_request_vote:798
> >>> ERROR: status
> >>>  = -107
> >>> Jul 16 17:06:43 enva11 kernel: (29933,2):ocfs2_rename:1196 ERROR: status
> >>> = -107
> >>>
> >>> The userspace error is a failed invocation of the mv command.  I know
> >>> that the return code is not 0, but didn't capture it.  I can re-run
> >>> tomorrow if that would be helpful.
> >>>
> >>> Thanks for your prompt response!
> >>>
> >>> Peace,
> >>> Andrew
> >>>
> >>> On Tue, 2007-07-17 at 15:31 -0700, Sunil Mushran wrote:
> >>>   
> >>>       
> >>>> It should behavw as you expect it to. That's the idea.
> >>>> What are the errors when mkdir fails?
> >>>> As in, userspace and dmesg.
> >>>>
> >>>> Andrew D. Ball wrote:
> >>>>     
> >>>>         
> >>>>> I would really like to see the following behavior:
> >>>>>
> >>>>> (1) I start with a two-node cluster, both nodes online, with an ocfs2
> >>>>> filesystem mounted on both nodes.
> >>>>> (2) I power off one of the nodes without unmounting the filesystem.
> >>>>> (3) The node that is still powered on continues to use the filesystem
> >>>>> mounted read-write with no problems.
> >>>>>
> >>>>> I believe I'm seeing that the node that is still online fails to write
> >>>>> data to the filesystem.  Specifically, mkdir(2) is failing.
> >>>>>
> >>>>> This is related to having a quorum right?  Can the quorum requirements
> >>>>> be disabled?  I have a file-backed database on the filesystem and my
> >>>>> entire software stack will be broken if any surviving nodes cannot
> >>>>> update the database.  Is there any reason why ignoring the quorum would
> >>>>> be not a good idea?
> >>>>>
> >>>>> Thanks for your help,
> >>>>> Andrew
> >>>>>
> >>>>>
> >>>>> _______________________________________________
> >>>>> Ocfs2-users mailing list
> >>>>> Ocfs2-users at oss.oracle.com
> >>>>> http://oss.oracle.com/mailman/listinfo/ocfs2-users
> >>>>>   
> >>>>>       
> >>>>>           
> >>> _______________________________________________
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> >>> Ocfs2-users at oss.oracle.com
> >>> http://oss.oracle.com/mailman/listinfo/ocfs2-users
> >>>   
> >>>       
> >
> >   
>