[Samba] File integrity in Samba/NFS environment

[tim clusters]

Hi,

I have a two server setup that acts as SMB as well as NFS servers in
active/active configuration managed by CTDB(http://ctdb.samba.org/).

When a file is updated by SMB clients(followed by file-close), other SMB
clients can see and modify the file. But when a NFS client (same user)
updates the same file(followed by file-close), only one SMB server can see
the updates. The clients mounting from other SMB server sees the file
corrupted. BUT, when you again update the file from any CIFS
clients(mounting from SMB server that can see the updates), the updates are
visible on all the CIFS clients.

My first suspect was to do with NFS and SMB caching. I forced NFS server to
export with sync option and same with SMB with the following, but does not
help:

strict allocate = yes
strict locking = yes
strict sync = yes
sync always = yes

NFS exports:
/mnt/gpfs/nfsexport *(rw,no_root_squash,sync,fsid=222)

Tried NFS mount with sync:
node1:/mnt/gpfs/nfsexport       /mnt/nfs        nfs
rw,tcp,hard,intr,sync,rsize=32768,wsize=32768,vers=3       0 0
smb.conf
[global]
        workgroup = TESTDOMAIN2
        realm = TESTDOMAIN2.LOCAL
        netbios name = CTDB-NAS
        server string = Clustered CIFS
        security = ADS
        auth methods = winbind, sam
        password server = 172.16.2.25
        private dir = /mnt/gpfs/CTDB_AD
        passdb backend = tdbsam
        client NTLMv2 auth = Yes
        log level = 3 winbind:5 auth:10 passdb:5
        syslog = 0
        log file = /var/log/samba/log.%m
        max log size = 10000
        deadtime = 15
        socket options = TCP_NODELAY SO_RCVBUF=16384 SO_SNDBUF=16384
        use mmap = No
        clustering = Yes
        machine password timeout = 999999999
        local master = No
        dns proxy = No
        ldap admin dn = cn=ldap,cn=Users,dc=testdomain2,dc=local
        ldap idmap suffix = dc=testdomain2,dc=local
        ldap suffix = dc=testdomain2,dc=local
        idmap backend = ad
        idmap uid = 5000-100000000
        idmap gid = 5000-100000000
        template homedir = /home/%D+%U
        template shell = /bin/bash
        winbind separator = +
        winbind enum users = Yes
        winbind enum groups = Yes
        nfs4:acedup = merge
        nfs4:chown = yes
        nfs4:mode = special
        gpfs:sharemodes = no
        fileid:mapping = fsname
        force unknown acl user = Yes
        strict allocate = Yes
        strict sync = Yes
        sync always = Yes
        blocking locks = No
        strict locking = Yes
        vfs objects = gpfs, fileid
[global-share]
        comment = GPFS File Share
        path = /mnt/gpfs/nfsexport
        read only = No
        inherit permissions = Yes
        inherit acls = Yes
Any idea to what I may be doing wrong?

Thanks in Advance,
-Tim