MTU size clarification at Interface and Sub-Interface level

[Sujanya]

Hi All, If we set mtu value as 9192 in interface and 9072 as sub-interface, which one the sub interface choose. If it will choose 9072, would that mean 9072 size packet can be sent. Similarly, If we set mtu value as 9192 in interface and kept the sub interface blank, what mtu will be choosen.

[kiwi]

Hi @Sujanya ,

Yes and if don't specify MTU value in the subinterface it will take default value (=1500).

Source: https://docs.paloaltonetworks.com/pan-os/11-0/pan-os-web-interface-help/network/network-interfaces/l...

Kind regards,

-Kiwi.

[Jean_Torres]

so even if you set the physical interface to 9142, you still have to set the sub-interface with the same MTU size? 

or since you set the physical interface to 9142 can you leave the sub-interface blank? or does it automatically take the default 1500?