Recently I had the need to show the MTU of an Fortinet Fortigate firewall interface. By default, if there are no changes the MTU will be 1500. But in this case I needed to be able to show that the MTU was 1500.
Few commands I tried did not show the exact info I needed, for example- Get hardware nic port1 – showed lots of great info but not the MTU.
To get this info I needed to do an Ifconfig from the Fortigate. to do this I ran the command:
fnsysctl ifconfig -a port1 Port1 being the port I needed to get the info for. Check out the screenshot below. Lots of other great info such as dropped packets and MAC.
source: https://travelingpacket.com/2017/08/25/fortigate-finding-mtu-of-an-interface/
