zfs, nfs and zil

[Claus Guttesen]

>> It's a supermicro server with dual igb-nics on the mainboard. I did
>> try other cables and other ports on the switch (hp procurve). I don't
>> have access to the server atm. but I'll get the chip-info in a day or
>> two. Both ip-addresses are on same subnet.
>>
>> Speed is autonegotiated to 1 GB full duplex on server and switch. No
>> errors detected using netstat or on switch.
>
> Something tells me (gut feeling) the virtualisation part is probably
> somehow responsible for the problem, quote:
>
>> I'm mounting the FreeBSD-server from a couple of vmware esxi 4.1
>> servers using nfs, but when there is alot of i/o the server becomes
>> unresponsive, easily triggered by installing ie. ms-sql. The server
>> itself is up but is not reachable from the network. When I take the
>> nic down and up again connection to the network is reestablished
>> (ip-wise).
>
> Can you remove ESXi from the picture and see if the problem continues?
> If it does, we should probably pull Jack Vogel into the discussion, as
> Supermicro predominantly uses Intel-based NICs.  He'll need output from
> "pciconf -lvcb" and "dmesg" to assist.
>
> But before pulling him in, please see if you can remove ESXi from the
> picture.

I've done some testing i Feb. when I initially installed the server
with samba and iscsi from a windows 7 client and managed to get
approx. 118 MB/s on plain GB nics. I copied some 30-40 GB and never
had a hickup. Then I mounted iscsi from vmware and migrated some
windows-servers and it behaved well.

When we moved to nfs the peculiar problems began to arise. I will redo
my testing from my windows 7 client to verify that my memory do not
put a spell on me!

I've also begun to move some virtual windows-servers back to iscsi and
mount the iscsi-volume from several vmware-servers. Vmfs is
cluster-aware and should handle it just fine. In a few days I'll move
a server I know causes problems to iscsi and I'll post the results.

Thank you for your input! :-)

-- 
regards
Claus

When lenity and cruelty play for a kingdom,
the gentler gamester is the soonest winner.

Shakespeare

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