RT-N66U - why no MTU/MRU adjust except on PPoE?

[tbessie]

Something I just noticed (tho' it was mentioned in the review here) was that the RT-N66U doesn't allow you to adjust the MTU/MRU value unless you're connecting to your ISP via PPoE. I'm using a static IP, so it won't let me change the MTU value.

I'd found that a specific MTU (1300 instead of 1500) got the best performance in my last router (WNDR3700); I was thinking that a Newer, Faster, Shinier router would have that feature... after all, most routers I've owned have allowed that; why would Asus tie an important feature like that to your WAN connection type? Anyone know? I'm not a network expert, but that seems completely arbitrary.

- Tim

 

[NobrakeS]

+1!
I'm on L2TP as recommended by my ISP for faster download rates. Also, the ISP recommends to use MTU 1460 and MRU 1500 for L2TP users.
Hense I checked this via Telnet & ifconfig in my RT-N66U and it showed 1500.
Is it crucial? Are there any ways to adjust this value?

 

[RMerlin]

+1!
I'm on L2TP as recommended by my ISP for faster download rates. Also, the ISP recommends to use MTU 1460 and MRU 1500 for L2TP users.
Hense I checked this via Telnet & ifconfig in my RT-N66U and it showed 1500.
Is it crucial? Are there any ways to adjust this value?

Sometimes path discovery will automatically take care of it for you. If not, you can always manually change it (but it won't survive a reboot, you would have to use my firmware and insert it in a user script):

ifconfig eth0 mtu 1460

This will however only affect the local ethernet port, I don't think it will do anything to your l2tp tunnel.