MTU Per vlan or Port base

[KarstenA]

Is it possible to run Jumbo frames 9K only on switchport or VLAN basis. Need this for a closed SAN network.

There are user vlans on that switch as well, change the default MTU size on the switch is no plausible 

[CptnCrnch]

You could run Jumbo Frames switch-wide and have all ports but the SAN ones have the standard MTU. Unfortunately, that‘s not possible with Meraki. 😞

[NolanHerring]

Maybe I've always misunderstood how this works. The default MTU size on switch settings is 9578. Isn't that already doing what you want?

I was always a little surprised to see that value, cause I thought I would have seen 1500 or 1522 there instead.

All my sites now that I think about it have that default value of jumbo frame enabled at the 9578. Starting to wonder if I should change it now lol

[PhilipDAth]

@NolanHerring  is right - Jumbo frames are enabled by default on Meraki switches.

With dynamic buffer management I don't see any point in changing it.

[KarstenA]

The problem is that the packets get fragmented at the firewall (ASA 5512-X) we got some issue with Microsoft Teams / Voice when fragmented

[KarstenA]

But that did not answer my question, is it possible for Meraki Support Engineer to change MTU by Port and VLAN basis

[PhilipDAth · Accepted solution]

No.