VSA design and performance

[cheazell]

Regarding splitting out the VM from the iSCSI are you guys using both eth0 and eth1 on the vsa for this? I'm feeling that I'm missing something here. I've disabled eth1 and have the VSA and the vmkernel ports on the same vswitch. Are you suggesting I change this? If so I assume they'd be on the same subnet? Here is a screen cap of my current vSwitch. Any pointers greatly appreciated!

Chris

[ialyoshin]

From my practice I would go with active/standby uplink config for VSA, it's more stable.

Also, almost in any case you won't get more than 1Gb. It is by design (1 working i/f at VSA, ESX iSCSI initiator going through 1 link,  VMware load balancing algorithm etc).

Also remember that you will have replication traffic between VSAs (but 1Gb full duplex helps). 

But this is virtual appliance. I thing 1Gb is quite ok for its normal tasks. Even 100Mb looks like to work )

Also I doubt you will have much more from 10Gb uplink. Taking 10Gb bandwidth from VM without root password and tuning is quite complex :).

I've written some notes on VSA here  , probably will be useful ..

[Sbrown]

I found the e1000e interface without flow control can easily push 10gbps in windows, even being a gigabit virtual interface that does not limit its speed but the flow control is not dialed in properly.

MY question is if you have two nodes, plus a 3rd for quorum, with esxi does the 3third node ever take requests and relay them? If so that would be a serious choke point since it has no data.

If esxi would only access two nodes, then vm's running on the same host as the VSA would have a 100% read hit rate locally but have to write to both nodes.?

[oikjn]

assuming your third node is a FOM....  no it will not have any data requests from your initiators.  Only nodes INSIDE the cluster will handle iSCSI requests and only for the LUNs inside that cluster.

[Sbrown]

so two nodes would be faster with a vm on a VSA node since you have a 100% chance of reading all data from localhost and 100% chance of writing all data to localhost (but have to way for 2nd host to ACK write).

I'd be curious how this works out compared to using more nodes where the remote data percentage would go way up?

[Prakash Singh_1]

Hi, For P4000 SAN solutions querries you can also visit the HP Guided troubleshooting tree. Below is the link for HPGT: http://h20180.www2.hp.com/apps/Nav?h_pagetype=s-905&h_lang=en&h_cc=us&h_product=304617&h_audience=smb&h_client=s-h-e010-1&h_audiencerestrict=true〈=en&cc=us