2.6.X File locking on NFS stil broken

2.6.X File locking on NFS stil broken

[Ruben Puettmann]

                hello,


I have a big iproblem with the nfs file locking on some 2.6 er kernel 

Kernel Server: 2.4.9
Kernel Client: 2.6.7-rc3-bk2
               2.6.6-rc3-mm2
               2.6.5

mount options :

10.0.0.149:/export     /mnt/server      nfs rw,auto,soft,bg,timeo=12,retrans=3,in tr,rsize=8192,wsize=8192,mountvers=3,nfsvers=3,udp  0  0

nfs-utils :  1.0.6

Both Server an Client Debian Sarge. Wiht kernel 2.4.21-pre5 the locking
runs very fine against the server.

This little testscript I  used ( got it from a friend):

#define _GNU_SOURCE
#include <unistd.h>
#include <stdio.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>

int main(int c, char **v)
{
    for (++v, --c; c--; ++v) {
        struct flock lck = {F_RDLCK, SEEK_SET, 0, 0}; /* whole file */
        int fd = open(*v, O_RDONLY);
        if ( fd < 0 )
            fprintf(stderr, "%s: %s\n", *v, strerror(errno));
        else {
            if ( fcntl(fd, F_SETLK, &lck) < 0 )
                fprintf(stderr, "%s[%d]: %s\n", *v, lck.l_pid, strerror(errno));
            else
                printf("%s..ok\n", *v);
            close(fd);
        }
    }
    return 0;
}


The programm hangs after executing ./script testfile. 


                        Ruben





-- 
Ruben Puettmann
ruben@puettmann.net
http://www.puettmann.net

Re: 2.6.X File locking on NFS stil broken

[Trond Myklebust]

P=E5 on , 09/06/2004 klokka 15:17, skreiv Ruben Puettmann:
>                 hello,
>=20
>=20
> I have a big iproblem with the nfs file locking on some 2.6 er kernel=
=20
>=20
> Kernel Server: 2.4.9
> Kernel Client: 2.6.7-rc3-bk2
>                2.6.6-rc3-mm2
>                2.6.5
<snip>
> This little testscript I  used ( got it from a friend):

That script works fine for me: I haven't seen any hangs on locking in
any of the 2.6 series kernels so far.

What does 'rpcinfo -p' show on the client and server?

Cheers,
  Trond

Re: 2.6.X File locking on NFS stil broken

[Ruben Puettmann]

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On Wed, Jun 09, 2004 at 05:13:43PM -0400, Trond Myklebust wrote:
> På on , 09/06/2004 klokka 17:03, skreiv Ruben Puettmann:
> 
> > attached the strace and one tcpdump from the testprogramm.
> 
> According to that tcpdump, the server is denying you the lock because it
> is still in its grace period. 
> 
> During that period only clients that held locks before the server
> rebooted are allowed to reclaim those locks. Your client will need to
> wait until that grace period is over (usually ~ 1 minute or so).
> 

I have done a reboot on teh server ( It was up for over 315 day's ;-( )
now all runs fine seems to be an race condition. I will take a look on
it if this happend again. 

Thanks for your help !!


                Ruben

-- 
Ruben Puettmann
ruben@puettmann.net
http://www.puettmann.net

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