ISCSI Slow Performance with 2003 SBS

[nsc]

Hi,

I have two servers connected directly by a switch to OpenE for iSCSI LAN, both at Gigabit.

One is a Windows 2008 Server, i have good performance when copying file on the ISCSI volume (80 - 90 Mo / s write).

Second is a Windows 2003 SBS and i have really bad performance.

The ISCSI Target have the same option on OpenE (C+A+W Iscsi Daemon Options Max Values possible), Jumbo Frame are OFF.

When copying data on my OpenE with SMB using ISCSI LAN from Windows 2003, i have really good performance, it's look like only my ISCSI from Windows 2003 is slow.

Any idea ?

Thanks

NSC

[symm]

hi nsc

Check the firmware on the nic in the 2003 box, make sure it is up to date.

[nsc]

Hy,

i did a full update of the server (IBM xSeries 346), reboot and no change...

Really strange.

[enealDC]

You may need to tune your TCP params. Windows by default uses Naggle algo on 2003/2000. Disable that. See the MS iSCSI User Guide under:

"Addressing Slow Performance with iSCSI Clusters"

[nsc]

Ok thanks, i did, it's better now

Now i have another question, looks like Bonding is useless. I try RR, XOR and TLB, i get better performance with Active-Backup (Best at 90Mo / s).

Any info about that ? Look like with 2 servers, i have to break my bonding and use dedicated NIC for each server right ?

[budy]

That depends also on the switches and how they cope with bonding. There're several posts about this "issue". Bonding had been originally desinged for fault-tolerance, not speed.

I couldn't get more performance out of a bond as well, so I devided indeed to wire the server through dedicated links to my DSS, or in my case: run multiple links in different networks from my server to my DSS.

I am starting to seriously thinking of getting a pile of 10 GbE gear.

Cheers,
budy