Slow Replication

[jon hatton-brown]

Hello, I've been following the guide to setup "synchronus volume replicaiton with failover over a lan" But when I get to the point when I start the replication task, the replication runs at about 500kB/s

I'm runnig DSS on the following hardware:

DSS1
HP Proliant DL180 G6
6GB Ram
twelve 600GB 15k SAS in Raid 5
two onboard 1GB Nic's
one dualport 1GB Nic's

DSS2
HP Proliant DL180 G6
6GB Ram
twelve 1TB 7.2k SATA in Raid 5
two onboard 1GB Nic's
one dualport 1GB Nic's

I've tried installing windows on them both and copying files from one to the other and it works at 125MB/s.

In DSS I tried creating NAS volumes on each of the DSS's and copying files onto them, and again it works at 125MB/s.

I've tried replication on both block and file volumes (both replicate at an average of 500kB/s).

Any ideas would be greatly appreciated.

[jon hatton-brown]

Update

I've tried installing Hyper-V Server on both the DL180 G6's and running DSS as a virtual machine thats set up in the same way. When running DSS in this way, I get no performance issues. I'm guessing this rules out hardware issues.

Anyone got any ideas?

[jon hatton-brown]

Hello,

I'm still having troubles with replication. I've tried installing Hyper-V on the two DL180 G6's, creating DSS v6 virtual machines, and re-testing. In this environment replication runs at high speeds.

So here are my findings so far

--Baremetal installation of DSS--

DSS1 to DSS2 - Slow replication

DSS2 to DSS1 - Slow replication

--Virtualised environment--
(Hyper-v installed in the DL180's, then DSS insalled as virtual machines)

DSS1 to DSS2 - Fast replication

DSS2 to DSS1 - Fast replication

--I then built a third DSS server (DSS3) on a desktop PC to test replication--

DSS1 to DSS3 - Fast replication

DSS3 to DSS1 - Slow replication

DSS2 to DSS3 - Fast replication

DSS3 to DSS2 - Slow replication

My thoughts on this are that reading from the DL180's works normally but DSS writing to either of them is verry slow. After installing windows on the hardware, I can file copy between the servers at high speeds.

[symm]

did you try to Set MaxRecvDataSegmentLength and MaxXmitDataSegmentLength to 65536
From the console CTRL-ALT-W, Tuning options, iSCSI Daemon options, Target
Options

[jon hatton-brown]

Thank you for your reply.

I've not got as far as creating an iSCSI target yet. It's the replication that is running slowly.

I looked at the page on the console, but it tells me that I have not created an iSCSI target.

[symm]

What kind of nic's do you have?
I had good luck with the intel pro/1000 nics