VM-VM affinity rule and port mirroring

[frigomiam2]

Hi,

I went through  http://blogs.vmware.com/vsphere/2013/01/vsphere-5-1-vds-feature-enhancements-port-mirroring-part-1.h...

At the bottom yan asked :

"What options are there for mirroring traffic from the VMs that are dynamically assigned to the hosts? In other words, what are the options for mirroring traffic when application mobility exists?"

and kalev answered :

"you may create DRS rule to keep source and destination VM-s together"

I don't find this info anywhere else in the vsphere 5.5 networking guide for example. It says only :

"

However, if the

source and destination move

to the same host, port

mirroring works."

I don't have lab right now to test that,

so does "Distributed Port Mirroring" works ok for vmotion if DRS VM affinity rule is used ? VMs will keep network connectivity to eachothers and traffic be mirrored continuously accross vmotions ?

thanks

[rcporto]

SPAN requires that source and destination port on the same host and you can accomplish this creating a VM Affinity (Keep Virtual Machines Together) in your DRS cluster... and about vMotion, if both VMs (source and destination) goes to the same host, the SPAN will works... anyway you cannot vMotion VMs in a VM Affinity rule to different host, DRS will not allow.

Thanks vickyvision2020 🙂

[vThinkBeyondVM]

Just one clarification on DRS rule:

VM-VM affinity is soft rule, if you want to migrate VM to other host, DRS will allow.

Only rule is must is VM-Host affinity must rule: This rule honored by HA even DRS is disabled.

Let me know if you need more info on rule.

[frigomiam2]

thanks for that,

one clarification again, will the "Distributed Port Mirroring" between these 2 VMs be continuous in an automated DRS cluster ? no interruption during vmotion of both VMs ..?

if I have DRS cluster and VM-VM affinity on 1 host, I understand that both VMs may be vMotioned to another host.as part of DRS calculation ?

Then during this vmotion, both VM will be registered at the same time on the other ESX, so the mirroring of traffic will be continuous ?

[vThinkBeyondVM]

As per me, port mirroring should continue to work even VMs are vMotioned.

Yes, if you have VM-VM affinity rule. These VMs can be vMotioned to some other host in order to balance the load by DRS. Load balancing has higer precedence over VM-VM affinity rules. Sometime, VM-VM affinity can be violated by DRS for balancing.