Use 'ifstat -z' to zero the stats and see if the errors are still currently occurring.  If they are occurring, and if still CRC's, check hardware starting with the easiest first: cable.

This would be why UDP *seems* to work while TCP "blows the whistle" on the errors.


----- Original Message -----
From: James Beal <james.beal@sanger.ac.uk>
To: Webster, Stetson
Cc: dh3@sanger.ac.uk <dh3@sanger.ac.uk>; toasters@mathworks.com <toasters@mathworks.com>; Blakemore, Steven
Sent: Wed Jun 11 13:40:52 2008
Subject: Re: strange behaviour, Linux and NFS on NTFS qtree

Webster, Stetson wrote:
>
> Any errors or strange numbers in 'ifstat -av' ?
>
netapp1a*> ifstat -v e4a

-- interface  e4a  (7 days, 10 hours, 23 minutes, 16 seconds) --

RECEIVE
 Frames/second:     311  | Bytes/second:     2251k | Errors/minute:    4864
 Discards/minute:     0  | Total frames:      277m | Total bytes:     63451m
 Total errors:    36939k | Total discards:      0  | Multi/broadcast:   108k
 No buffers:          0  | Non-primary u/c:   101k | Tag drop:            0
 Vlan tag drop:       0  | Vlan untag drop:     0  | Mac octets:        132g
 UCast pkts:       1187m | MCast pkts:      17000  | BCast pkts:      91533
 CRC errors:      36939k | Bus overrun:         0  | Alignment errors:    0
 Long frames:         0  | Jabber:              0  | Pause frames:        0
 Runt frames:         0  | Symbol errors:       0  | Jumbo frames:        0
TRANSMIT
 Frames/second:     433  | Bytes/second:     1506k | Errors/minute:       0
 Discards/minute:     0  | Total frames:      563m | Total bytes:      3323g
 Total errors:        0  | Total discards:      0  | Multi/broadcast:  7559
 Queue overflows:     0  | No buffers:          0  | Frames queued:       0
 Buffer coalesces:    4  | MTUs too big:        0  | Mac octets:       3462g
 UCast pkts:       2452m | MCast pkts:       2922  | BCast pkts:       4637
 Bus underruns:       0  | Pause frames:        0  | Jumbo frames:        0
LINK_INFO
 Current state:       up | Up to downs:         1  | Speed:           10000m
 Duplex:            full | Flowcontrol:       full

It's using a 10Gig card with no vif's ( I believe ) . When we stress the
system we see the following on the console , although when we do this
test we don't see the problem ( We see it when I throw about 1000 cores
at the system and the 10Gig card is at about 60% and the CPU is around
100% ). I have asked our presales engineer about this.

>>
>>
>> XXX restart_tx
>> restart_offloadq
>> XXX restart_tx
>> XXX restart_tx
>> restart_offloadq
>> XXX restart_tx
>> XXX restart_tx


>
> ----- Original Message -----
> From: Dave Holland <dh3@sanger.ac.uk>
> To: Webster, Stetson
> Cc: toasters@mathworks.com <toasters@mathworks.com>
> Sent: Wed Jun 11 11:58:38 2008
> Subject: Re: strange behaviour, Linux and NFS on NTFS qtree
>
> On Wed, Jun 11, 2008 at 11:30:22AM -0400, Webster, Stetson wrote:
> > What ONTAP release, what Linux kernel, what NFS mount options?
>
> I knew I'd missed things...
>
> It's ONTAP 7.2.4. I can upgrade to 7.2.5 if that'll help.
>
> The Linux kernel is 2.6.18-6-686 (Debian 4.0, 2.6.18.dfsg.1-18etch4),
> and the problem also shows with 2.6.8-2-686-smp and
> 2.6.5--286tg3susesfs.
>
> I noticed this when mounting with proto=tcp,vers=3,rsize=8192,wsize=8192.
> I'd also tried UDP, and the problem persisted.
>
> But after your email I tried vers=2 and the problem goes away (with both
> TCP and UDP) which is interesting indeed. Although with the crazy size
> files and filesystems around here, NFSv3 is very desirable.
>

--
james beal


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