From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wendy Cheng Date: Mon, 07 Aug 2006 17:03:11 -0400 Subject: [Cluster-devel] Re: [NFS] [PATCH 0/3] NLM lock failover In-Reply-To: <44D79F26.B93E5C00@sgi.com> References: <44A41246.2070106@redhat.com> <1154397341.3378.10.camel@localhost.localdomain> <1154683665.21040.2431.camel@hole.melbourne.sgi.com> <1154698079.3378.2.camel@localhost.localdomain> <1154703362.3378.45.camel@localhost.localdomain> <1154706709.4727.21.camel@localhost> <1154756682.3384.34.camel@localhost.localdomain> <1154923557.29877.106.camel@hole.melbourne.sgi.com> <44D79F26.B93E5C00@sgi.com> Message-ID: <44D7AA8F.4020109@redhat.com> List-Id: To: cluster-devel.redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit James Yarbrough wrote: >>>take-over server: >>>B-1. mount the subject filesystem >>>B-2. "echo 1234 > /proc/fs/nfsd/nlm_set_ip_grace" >>>B-3. "rpc.statd -n 10.10.1.1 -N -P /shared_storage/sm_10.10.1.1" >>>B-4. bring up 10.10.1.1 >>>B-5. re-export the filesystem >>> >>> >>Umm, don't you want to do B-3 after B-4 and B-5 ? Otherwise >>clients might racily fail on the first try. >> >> > >I don't think they will necessrily fail. It depends on whether the >server sends ICMP unreachable messages and how the client responds to >those. In any case, I think the ordering should be B-5, B-4, and B-3 >last. One can argue about the ordering of B-3 and B-4, but if exporting >(B-5) does not happen before bringing up the IP address (B-4), clients >can get ESTALE replies. For better transparency, it's probably best >to avoid ESTALE. > >It's probably OK to do step B-3 after bringing up the IP address since >that will mimic what happens during boot. > > Yes, you and Greg are mostly right - that was an oversight from my test script. But our user mode RHCS script (Lon wrote that piece of code) does it correctly. He did B-5, B-4, and B-3 last. Adding export: *:/mnt/tank1 (fsid=9468,rw) Adding export: *:/mnt/tank2 (fsid=661,rw) Link for eth0: Detected Adding IPv4 address 10.15.89.203 to eth0 Sending gratuitous ARP: 10.15.89.203 00:30:48:27:92:d6 brd ff:ff:ff:ff:ff:ff Sending reclaim notifications via tank-02 Start of nfs1 complete -- Wendy