access ports to trunk ports - no (or minimal) downtime

[sdmikev]

Taking over for someone and not an expert yet, so forgive me if this is rather simple.  I've done a fair amount of searching and haven't seen an answer yet.

There are 4 hosts in a cluster - Nutanix - the NIC's are all into 1GB ports in one switch for one subnet (call it .128/25) currently configured as access ports - no VLAN ID is set on the vm network ports and we're using standard vswitches.  The port group is called "VM Network".

I have 8 new ports on both physical switches now configured with trunking with VLAN ID's and 4 VLANS that are going to be necessary in this cluster - hence the change.  One of the subnets will be the above .128/25 I noted.

If I vacate a host, move the cables and configure the port groups for each of the 4 subnets calling them prod1 through prod4, once the host starts tagging packets will I be able to vmotion to the newly configure host from one of the other three? 

Thank you,

Mike

[rcporto · Accepted solution]

Since you cannot vMotion VMs from one host to another if port group name differs, my recommendation is:

1. evacuate VMs from host that you want create the new port groups with VLAN tagging;

2. create the new port groups with appropriate names and VLANs;

3. on host without VLAN tagging, create same port groups but without VLANs;

4. change the VMs virtual network interface to the appropriate new port group;

5. vMotion the VMs to the new host.

[sdmikev]

Thank you, that makes sense.

When adding the new port groups to a host still containing VM's, I assume that without tagging, all the port groups (for the moment) will just use the existing subnet.  When I change the network to prod1 or whatever on the VM's, they'll just drop a few packets, then I can vmotion them.

[rcporto]

You're welcome,

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