On Fri, 22 Jul 2011 13:24:22 +0200 Michael Schwartzkopff <misch@xxxxxxxxxxxxxxxxx> wrote: > > On Thu, 21 Jul 2011 15:40:05 +0200 > > > > Michael Schwartzkopff <misch@xxxxxxxxxxxxxxxxx> wrote: > > > Hi, > > > > > > setting up a linux NFS server cluster I experience a strange problem > > > during a failover. A client can access a file only after 60 to 90 > > > seconds. On the line I see a NFS4ERR_GRACE from the server to the > > > client. > > > > > > I already set the /proc/fs/nfsd/nfsv4leastime to 10. > > > > > > Any other idea? > > > > > > For the tests I have a simple setup: > > > > > > One host with a simple script that simulates failover: > > > > > > #!/bin/bash > > > > > > ip a d 1.2.3.4/24 dev eth0 > > > exportfs -u *:/srv/nfs/home > > > exportfs -u *:/srv/nfs > > > /etc/init.d/nfsserver stop > > > # > > > /etc/init.d/nfsserver start > > > exportfs -o fsid=0,rw,crossmnt,no_root_squash *:/srv/nfs > > > exportfs -o fsid=1000,rw,mountpoint,no_root_squash *:/srv/nfs/home > > > ip a a 1.2.3.4/24 dev eth0 > > > > This is normal. The grace period is there to allow clients to reclaim > > their state without other clients racing in and grabbing their locks on > > the new server, etc. > > Ok. But this is the same client that cannot its own data. > That may be the case in your situation, but the protocol has to allow for that. > > You can play with /proc/fs/nfsd/nfsv4gracetime too but I'd be very > > leery of setting that too low. It should never be lower than the > > previous leasetime (see the comments on write_gracetime in the kernel). > > I did already set this to 10 seconds without success. The client still has to > wait 60 seconds to access its data. > You may need to restart the server and remount the clients in order for it to work. > By the way: Is there a nice way to set this during startup of the nfsserver, > i.e. a mount option for nfsd? > Not currently, but a module parm for this would seem to make more sense than this file in /proc. -- Jeff Layton <jlayton@xxxxxxxxxx> -- 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
