C9800-CL multiple VLAN SVIs same mac

[Clem58]

Hello,

I've deployed a C9800-CL Hyperv VM, I have created 2 VLAN SVIs, they got the same mac address.

Is this something normal ?

Thanks by advance

[Scott Fella]

When I have deployed the 9800-CL, I only used one SVI and that was used for management and wireless.  What is the reason you need to have more than one?  I'm just curious.

[Clem58]

I need to add one for using central switching (guest access)

[Scott Fella]

So you are implementing FlexConnect, but you want to tunnel guest back to the 9800 VM?  Why not just keep the guest local and use vrf to isolate that traffic.

[Clem58]

There is no guest local, for 2 sites, so I need to use the guest where the
WLCs are connected.

Anyway we have the possibility to create multiple SVIs, so realizing they
have the same mac, I wonder if this is something intended by Cisco ?

[Scott Fella]

No idea because you typically don't need to configure an SVI on the 9800 for clients.  Just pass the vlan tag and let the upstream L3 do the routing.

https://www.cisco.com/c/en/us/products/collateral/wireless/catalyst-9800-series-wireless-controllers/guide-c07-743627.html#Wirelessclientinterfaces

[Clem58]

Ok yes you're right Scott, I wanted to add this svi to be able to ping the router that is in this VLAN, for checking, to be sure connectivity was working.

I saw this same mac for the both mgmt vlan and guest so that was my question

[Scott Fella · Accepted solution]

I would have to say that it is by default since you have seen it.  I have also added an SVI on my home lab 9800 and the Mac address is the same.

[Clem58]

Thanks Scott !