[Samba] Samba on top of NFS question

[Ryan Taylor]

Thank you for the reply, its nice to know someone else is in the same boat.

Unfortunately our servers are also in production and therefore we can't try
the patch.  We also have not found a good way to reproduce without throwing
all the users on the system.

One interesting fact I have noticed since we have moved our data to the
local samba machine: netstat -s -u returns
# netstat -s -u
Udp:
    50898 packets received
    16 packets to unknown port received.
    0 packet receive errors
    17163 packets sent
#
Where as before when on NFS we had 50%-75% of the number of "packets
received" in "packet receive errors"

I am beginning to believe you are right, NFS cannot handle the locking
required by Samba?

I am confused in two directions.  We use Whitebox4 and have noticed a
newer version of nfs.utils.el4 rpm released but requires (because of two
many dependencies) for use to upgrade to CentOS4... 2) We are using AMD X2's
so are running the SMP kernel as well.  Could it be just a SMP issue? Which
is why I am curious if anyone else had samba working in an environment
similar to ours.


On 2/27/06, Fermin Molina <fermin at asic.udl.es> wrote:
>
> On Mon, 2006-02-27 at 15:11 -0500, Ryan Taylor wrote:
> > I am sorry for the long *involved* post, however we are at wits end and
> > advice would be greatly appreciated.
> >
> > Background: We have three servers in this example.  Two of the servers
> (we
> > will call Server A & B) each have a 2.7T raid 5 array that is mirrored
> with
> > DRBD and monitored for failover with Heartbeat.  NFS is running and
> > exporting the array on Heartbeats virtual IP.
> > "Server C" mounts the export, and is a Samba PDC.  The mount contains
> all
> > project data which samba hands out to ~250 windows boxes.  There are at
> > least ~1600 files open(locked) at any given time throughout the day.  It
> > works, kinda.  The users can work and everything is fine except we get
> > somewhat random, usually 2 freezes a day.  The windows boxes freeze up
> for a
> > few minutes then resume working like nothing happened.  The servers go
> idle
> > during this "freeze", and sometimes we get the " lock.d can't reach
> server"
> > then "ok" messages in dmesg, but other times not.
>
>
> Look the thread "Samba daemons hang trying to lock locking.tdb", about
> Jan 25 in this list.
>
>
> > The post is long enough without telling you all that we have tried.
> (long
> > list including network drivers, nfs mount options, samba locking
> options,
> > etc..).  We now have data on "Server C" and Samba hosting it off it's
> local
> > drives.. It's only been one day so far, but so far (knock on wood) no
> > freezes.  In addition samba runs much smoother on the clients end, such
> as
> > (*right-click*properties boxes etc...) Segue to question...
>
>
> I've solved the problem reducing the amount of data shared with NFS
> (making it "local" to the machine I run samba).
>
> It's a problem (I think) with linux kernel and file looking. Have a look
> to the thread "kernel BUG at fs/locks.c:1932!" of linux-kernel list,
> about Fri, 17 Feb 2006.
>
> I use latest kernels from FC4. Can you try the patch to linux kernel
> from "Trond Myklebust"? I cannot try it, because my server is in
> production.
>
> I will post to this list my conclusions when I finish the investigations
> about this behaviour.
>
>
> > Question(s):  Does Samba not work on top of NFS? Is there any better way
> for
> > Samba to access the data on the failover pair of servers than NFS?  Is
> it
> > locking that is causing us problems? What is the correct 'Samba' way to
> get
> > remote data shared to multiple samba front ends?  I guess my ultimate
> > question and why I am posting, is because I have tried TONS of things
> and am
> > curious if anyone else has this particular setup working?
>
>
> I have used FC3 (with latest updates) with samba 3.0.14a, and the same
> configuration (NFS, etc) and all was working ok. When I changed the
> server and begin to use the latest FC4 with last versions of linux
> kernel and samba, all goes very very bad.
>
> Cheers,
>
> --
> Fermin Molina Ibarz
> Tècnic sistemes - ASIC
> Universitat de Lleida
> Tel: +34 973 702151
> GPG: 0x060F857A
>
>
>


--
Ryan Taylor
Micro Consultants
770-789-2072
rtaylor82 at gmail.com
"Until I see everything working right, I will be apprehensive."  Pamela
Klabbers