Distributed Networking - Increase Ports or add new dvSwitch/dvPortgroup

[Shocko]

Hi guys,

I'm wondering what criteria one uses when deciding to increase the number of ports as opposed to adding a new PortGroup or dvSwitch. Obviously, dvswitches cannot share uplinks so you would need a new dvSwitch if the bandwidth was saturated on those uplinks or if the upstream networking was different (i.e. DMZ  etc.).  When it comes to increasing ports though on either the PortGroup or the dvSwitch, would you only do that when you wanted VMs on that dvSwitch/PortGroup in order to inherit that config (NetFlow/Security etc. ) ? is there a performance overhead with increasing the number of ports?

[JPM300]

If you have a portgroup in your VDS that hasn't reached the max ports # yet and you want more systems to be on that port group there is no harm in increasing the port size.  The only thing you have to watch out for is to make sure your uplinks are not being saturated or won't become saturated with that port group being increased.  If that is not an issue there is no harm in increasing it.  However if you want more separation or want these new groups to go to different uplinks you would probably be better off creating a new port group and placing them there.

Here is the links to the maxims

http://www.vmware.com/pdf/vsphere5/r50/vsphere-50-configuration-maximums.pdf

Hope this has helped

[Shocko]

Thanks for the reply,

I should have mentioned my ESXi 5.1 hosts are behind HP Virtual connect Flex-10 so each up-link is running at least 3 GB. The entire HP enclosure egress/ingress is only averaging around 7-00 MB on 20 GB Shared Uplink sets  so should be no issues with saturation. I was more wondering if each dvSwitch introduced significant overhead on the hyper-visor. Finally, can you increase the port count on the fly without disruption?

[JPM300 · Accepted solution]

It appears it requires a reboot of the host to take effect

http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=200407...

So this may require some testing.  I haven't had to do it in forever, so you might want to test it out in a lab first