Edit MTU VPN s2s

[NicolasBou]

Hi all,

I would like to modify the default MTU from 1500 to 1270 to avoid fragment on one of my VPN tunnel.

This tunnel is set up on vlan used by a lot of critical equipment.

Can i change the MTU for this tunnel specifically or have to do it on the VLAN Interface ?

i would like to avoid to disconnect those equipement during the operation.

Thanks for your help,

N.B

[Flavio Miranda]

Hi @NicolasBou

 As per ASA documentation you can change the MTU for an Interface. The problem is that you probably use the Outside interface for VPN and Internet traffic, so, if you change it, this will affect any traffic trans-passing that interface. Unless you have a dedicated interface for VPN traffic.

-If I helped you somehow, please, rate it as useful.-

[NicolasBou]

Yeah the VPN interface is using the outside interface :/

So i have to change it on the hardware interface (outside) and not on the logical interface (VLAN interface) ?

Thanks for your answer Flavio ;)

[Flavio Miranda · Accepted solution]

Yes. You can see this through the command:

mtu interface_name bytes

-If I helped you somehow, please, rate it as useful.-

[NicolasBou]

okay thanks !