VMotion network

[filcap]

Hello!

I have a cluster of 4 servers; I don't have a GigaBit switch (it's just 100Mb)...

I can use 6 nics for each server. I want network redundancy.

Until yesterday I had 2 servers in the cluster and I used 2 nics to connect the servers by a couple of cross cables. With the virtual switch connected to the team of these two nics I implemented an internal network and the vmotion network.

What is the best way to implement the vmotion network in the new configuration with 4 servers? (I know that the best would be to buy a GigaBit switch, but it is not possible at present...)

Can I implement several "point to point " vmotion networks each one between 2 servers??

Any help will be really aprecicated!

Filippo

[max_inglis · Accepted solution]

I believe the best practice is to have the VMotion network sharing the same 2 nics as your service console, but have them using opposite primary NICs, with the other for failover.

vswitch0 will have port groups for "Service Console" and "VMotion". Assign 2 of your NICs to the vswitch. Then for Service Console port group, assign 1 nic as active, and the other to standby. Assign the opposite nic to active on VMotion port group, and use the rest of your NICs for guest traffic.

[Texiwill]

Hello,

I believe the best practice is to have the VMotion network sharing the same 2 nics as your service console, but have them using opposite primary NICs, with the other for failover.

This is an acceptable practice is it NOT a best practice. Best practice would be to have a separate vSwitch just for VMotion.

If you only have two nodes then you can use a cross over cable for VMotion, but not if you have more than 2. Then you need a vSwitch.

Best regards,

Edward L. Haletky

VMware Communities User Moderator

====

Author of the book 'VMWare ESX Server in the Enterprise: Planning and Securing Virtualization Servers', Copyright 2008 Pearson Education.

SearchVMware Blog: http://itknowledgeexchange.techtarget.com/virtualization-pro/

Blue Gears Blogs - http://www.itworld.com/ and http://www.networkworld.com/community/haletky

As well as the Virtualization Wiki at http://www.astroarch.com/wiki/index.php/Virtualization

[max_inglis]

Hrm well the VMware professional services person who was here last week told me that was the best practice. I'll keep their name out of it if they really were wrong. I think obviously if you can spare the NICs then separating everything is best regardless. They may have been talking about situations where you are limited in NICs.

On that tangent, how do you separate VMotion and vmkernel traffic onto different vswitches? When you try to assign NFS how does it know not to use the VMkernel port assigned to VMotion? Is it the act of checking off "Use for VMotion" that makes it not be used for anthing else?

[Texiwill]

Hello,

Hrm well the VMware professional services person who was here last week told me that was the best practice. I'll keep their name out of it if they really were wrong. I think obviously if you can spare the NICs then separating everything is best regardless. They may have been talking about situations where you are limited in NICs.

It is a best practice in that situation.

On that tangent, how do you separate VMotion and vmkernel traffic onto different vswitches? When you try to assign NFS how does it know not to use the VMkernel port assigned to VMotion? Is it the act of checking off "Use for VMotion" that makes it not be used for anthing else?

Given:

SC: 10.100.100.1

VMotion: 10.200.100.1

NFS: 10.300.100.1

Gateway: 10.100.100.254

vmkernel Gateway: 10.200.100.254 traditionally for VMotion.

NFS tries to use network 10.300.100.0 so if your NFS server is on that network then everything should be fine. All access to this network is over the NFS vmknic. If it is not on this network it will attempt the vmkernel gateway which may or may not be on the same network. If it is not, then you get failures due to netmask issues. The SC is uninvolved in this process.

Best regards,

Edward L. Haletky

VMware Communities User Moderator

====

Author of the book 'VMWare ESX Server in the Enterprise: Planning and Securing Virtualization Servers', Copyright 2008 Pearson Education.

SearchVMware Blog: http://itknowledgeexchange.techtarget.com/virtualization-pro/

Blue Gears Blogs - http://www.itworld.com/ and http://www.networkworld.com/community/haletky

As well as the Virtualization Wiki at http://www.astroarch.com/wiki/index.php/Virtualization

[max_inglis]

Thats what I wanted to be sure of so I design the NFS portion of our network correctly. Thanks for the info.

Max.

http://ITangst.blogspot.com