How to force MTU on PPPoE interface

« previous next »

Print

Pages: [1]

Author Topic: How to force MTU on PPPoE interface (Read 2342 times)

hushcoden

Hero Member
Posts: 544
Karma: 23

How to force MTU on PPPoE interface

« on: July 20, 2020, 09:27:53 pm »

I'd like to test MTU=1500 on my PPPoE interface, but if I enter the value on 'interfaces' -> 'wan' -> MTU and saving it doesn't actually change it (still 1492): is there a way perhaps through CLI to force the value to 1500?

Tia.

Logged

Alphabet Soup

Newbie
Posts: 47
Karma: 7

Re: How to force MTU on PPPoE interface

« Reply #1 on: July 21, 2020, 01:54:15 pm »

Haven't done it myself but this thread from when RFC 4638 support was added to OPNsense should give you something to try: https://forum.opnsense.org/index.php?topic=2238.0

Logged

franco

Administrator
Hero Member
Posts: 17656
Karma: 1611

Re: How to force MTU on PPPoE interface

« Reply #2 on: July 21, 2020, 04:01:03 pm »

If I recall correctly you actually have to input the oversize MTU of 1508 to reach the 1500 MTU?

Cheers,
Franco

Logged

franco

Administrator
Hero Member
Posts: 17656
Karma: 1611

Re: How to force MTU on PPPoE interface

« Reply #3 on: July 21, 2020, 04:11:23 pm »

PS: Now I remember 8 byte is the PPPoE header that needs to be subtracted anyway

Logged

hushcoden

Hero Member
Posts: 544
Karma: 23

Re: How to force MTU on PPPoE interface

« Reply #4 on: July 21, 2020, 04:59:18 pm »

Thank you both, with 1508 it works

Logged

Print

Pages: [1]

« previous next »