On Mon, May 5, 2008 at 11:58 AM, J. Bruce Fields <bfields@xxxxxxxxxxxx> wrote: > > So the let the user worry approach. Statd does not > > notify anyone and user is supposed to do it with > > sm-notify manually. > > We should modify distro startup scripts to run sm-notify and add -L to > statd, following the recommendations in nfs-utils/README. > > That will leave the -v option to sm-notify, which will need to be added > somehow to handle the highly-available-nfs case. Humm ... imho this does not add anything to current 1.1.* tree. Exactly same things happen when -n is being used. > > This will work, but -n looks cleaner me.. > > I've lost the thread here a little. Let me try to summarize, and tell > me what I've forgotten: > > So we've got multiple nfs servers that may serve the same export. Only > one serves a given export at a time. > > To keep the clients from having to understand this, we tell them to > mount a single "floating" ip address, and when we want to use a > different server, we move that floating ip address, and the clients > automatically follow it. The only problem is that the new server > doesn't know about locks held on the old server. We solve that problem > by telling clients that the server has rebooted, and that they must > reclaim locks. > > To make that work, we need to ensure that statd notifies the clients > that "floating-ip" has rebooted. (They will get confused if they are > notified that "some-other-ip" has rebooted, where "some-other-ip" is > just some random ip that the new server happens to use on a different > interface.) Exactly right. > The statd -n option has actually *never* worked, in any previous version > of nfs-utils--with it specified, statd can no longer communicate with > the nfs server on the same host. That means the server won't find out > when a client reboots. (But I guess even the broken -n may still have > been sufficient to allow clients to monitor the server and find out when > the server reboots.) -n may work as is in 1.1.* tree: a) It will bind to ANY, so kernel lockd will see packets coming in from LO. 1.0.x bound the -n interface which will break. b) sm-notify is run with -v and correct name (that will bind to correct IP and use the right name) So the only thing missing would be to limit the port visibility of long-standing sockets; but this should probably be discussed in another thread if you think it's worth it? -- // Janne -- 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
