It is currently Thu Jan 21, 2021 8:59 am
All times are UTC + 8 hours

How to Change MTU Manually?

Share your awesome tips and tricks here.

How to Change MTU Manually?

Postby Zaragosa » Wed Nov 27, 2019 8:24 am

Currently using latest version, 3.4.5.RBJ3, prior to ADM update I was able to set MTU to any value. The values listed are now hard; 1500, 2000, 3000, 4000, 5000, 6000, 7000, 8000, and 9000.

How do I change the MTU size to a value not listed under Settings->Network->Network Interface-><Configure>? I want to set the MTU to 1492.

Thanks in advance
Zaragosa
 
Posts: 32
Joined: Thu May 08, 2014 6:27 pm

Re: How to Change MTU Manually?

Postby father.mande » Wed Nov 27, 2019 4:01 pm

Hi,
Zaragosa wrote:Currently using latest version, 3.4.5.RBJ3, prior to ADM update I was able to set MTU to any value. The values listed are now hard; 1500, 2000, 3000, 4000, 5000, 6000, 7000, 8000, and 9000.
How do I change the MTU size to a value not listed under Settings->Network->Network Interface-><Configure>? I want to set the MTU to 1492.
Thanks in advance


MTU is by definition a maximum, so negotiated by the 2 end points
... so if on point propose 1492 the other 1500 the real used MTU is 1492

MTU have multiple definition due to change in link support
... for ex. 1492 and 1500 are same if one implementation use the definition (as for ADSL) without I.P. headers (8) or with include headers ... so 1500 (I repeat negotiated) is a current proposal to support each case

In all case you can try to set the MTU you want ... if the hardware (Ethernet chip) and the software (network stack) support it by using the command ip
... ip link set or down / set / up (use a script and start it in a screen or tmux to avoid terminal ssh / telnet disconnection)

Take care if something goes wrong ... you can lost network access, so
... test on one Ethernet if you have multiple Ethernet (and configure the second to keep an access)
... or use a short reset to return to basic network and password configuration without loosing data and application.

I suppose a script exist somewhere in /usr/builtin/etc ... but I have no time to search it ...

Philippe.
AS5202T /AS5002T / AS202TE / AS1002T
My Blog specific to my APKG : https://blog.father-mande.ovh/
User avatar
father.mande
 
Posts: 1063
Joined: Sat Sep 12, 2015 2:55 am

Return to Tips & Tricks

  • You cannot post new topics in this forum
    You cannot reply to topics in this forum
    You cannot edit your posts in this forum
    You cannot delete your posts in this forum
    You cannot post attachments in this forum
  • Who is online

    Users browsing this forum: No registered users and 1 guest