Hello Wendy. On Friday 25 April 2008 15:47:03 Wendy Cheng wrote: > Bernd Schubert wrote: > > Hello, > > > > on servers with heartbeat managed resources one rather often has the > > situation one exports different directories from different resources. > > > > It now may happen all resources are running on one host, but they can > > also run from different hosts. The situation gets even more complicated > > if the server is also a nfs client. > > > > In principle having different nfs resources works fine, only the statd > > state directory is a problem. Or in principle the statd concept at all. > > Actually we would need to have several instances of statd running using > > different directories. These then would have to be migrated from one > > server to the other on resource movement. > > However, as far I understand it, there does not even exist the basic > > concept for this, doesn't it? > > The efforts have been attempted (to remedy this issue) and a complete > set of patches have been (kept) submitting for the past two years. The > patch acceptance progress is very slow (I guess people just don't want > to get bothered with cluster issues ?). Well, I think people are just ignorant. I did see your discussions about NLM in the past on the NFS mailing list, but actually I didn't understand the entire point of discussion ;) I was simply used to active-passive services (mostly due to heartbeat-1.x) and there we just had /var/lib/nfs linked to the exported directory. After I started to work here, I was confronted with the fact we do have working active-active clusters here, but nobody besides me ever cared about the locking problem :( NFS failovers just are done ignoring file locks. Seems so far also nobody run into a problem, but maybe the result was so obscure that nobody ever bothered to complain... I'm just afraid most admins will simply do like this... > > Anyway, the kernel side has the basic infrastructure to handle the > problem (it stores the incoming clients IP address as part of its > book-keeping record) - just a little bit tweak will do the job. However, > the user side statd directory needs to get re-structured. I didn't > publish the user side directory structure script during my last round of > submission. Forking statd into multiple threads do not solve all the > issues. Check out: > https://www.redhat.com/archives/cluster-devel/2007-April/msg00028.html Thanks, I will read this! Thanks again, Bernd -- Bernd Schubert Q-Leap Networks GmbH -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
