Migrating to a new physical switch - any tips?

[JoshRountree]

We currently have 2 Cisco 3560, and are migrating to 2 Cisco 3850 in a stack.

We have 2 hosts, each with 8 physical NICs

• vSwitch0
  • nic0, nic4
  • vMotion and MGMT
• vSwitch2
  • VM network
  • nic1, nic2, nic5, nic6
• vSwitch3
  • SAN/storage
  • nic3, nic7

We have an EMC VNXe3100 SAN with dual storage processors

I think everything will fail over accordingly, but our VCenter server is on the same subnet as our VM network, so if I disconnect the gateway VCenter won't be able to communicate with the hosts. I doubt this will be a big deal, but wondered if anyone had any tips?

Thanks

[rcporto]

The new switches are already connected to the network ? Which teaming load balance you're using on ESXi ?

[JoshRountree]

They're not connected yet, 1 of the 3560 is the default gateway for the subnet that the VMs are on as well as VCenter.

We'll be migrating the default gateway to one of the 3850s.

Shutting everything down, converting over, and then powering back up is an option, but not my favorite...

[rcporto · Accepted solution]

You forgot to told me which teaming load balance you're using on ESXi ? Anyway, if you aren't using the IP Hash, you can do the following:

1. connect the new switch to the old, using a trunk port (allowing all VLANs);

2. configure the ports on the new switch to support the connections from the old switch;

3. configure the VLAN interface (including the IP) but do not enable this interface;

4. move all ESXi uplinks to the new switch, try move one by one and verify connectivity between each move;

5. move all other connections from the old to new switch;

6. shutdown the VLAN interface on old switch and enable the VLAN interface on new switch.

[JoshRountree]

Dang, sorry, but we aren't using IP hash.

We are using explicit failover on the vmotion, mgmt, and storage vswitches/portgroups. We are using virtual port ID on the VM port group.

This is a HUGE help and makes a ton of sense, thank you!

[rcporto]

You're welcome and let me know any additional doubt.

[jrmunday]

On a side note ... Given the number of uplinks you're using, I assume they are all 1GB? If you're not already doing so, you could consider doing multi-nic vmotion (for the cost of 1 additional IP address).

Additionally, if you're licensed with Enterprise Plus consider the use of distributed virtual switches as you can do load based teaming.

With 1GB uplinks, I find that trunking all networking to all ports gives me a great deal of flexibility to cater for any requirements.

Cheers,

Jon