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

[jon hatton-brown]

I've been using HP NC360T's, which use the Intel 82571EB chipset.
I've also tried the HP NC362i (not sure which chipset they are)

[jon hatton-brown]

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

The Intel pro/1000's I have access to are PCI-X, the DL180 G6 only has PCI-E slots.

[King-Dude]

Hi,

I dont think its the hardware, i can help you out for a small fee, just drop me a mail and we can talk over there if you want to. alias_the_dude (at) live.se

You can see my previus post. http://forum.open-e.com/showthread.php?t=1737

[symm]

Hey King-Dude

What happened to the spirit of helping one another, That is what the forums are for!
If you want to make some money, Setup your own website and stop leaching.



jon hatton-brown

you may want to try downloading the logs and send them to open-e support.
They have free support

also check other post on the this forum to see what others have done to improve the replication speed.