PPPoE server MTU with netonix switch and ubiquiti AP/CPE

RouterOS General
1

Hi, i need some help with this topology. In need pass full frame MTU, but i don’t understanding where i could change the values.

This is my topology and MTU values:

More details:

And this is the PING with do-not-fragment from the customer laptop. Like you can see i be able to pass 1452 packet sizes.

C:>ping 10.15.15.254 -f -t -l 1452

Pinging 10.15.15.254 with 1452 bytes of data:
Reply from 10.15.15.254: bytes=1452 time=7ms TTL=63
Reply from 10.15.15.254: bytes=1452 time=27ms TTL=63
Reply from 10.15.15.254: bytes=1452 time=38ms TTL=63
Reply from 10.15.15.254: bytes=1452 time=4ms TTL=63
Reply from 10.15.15.254: bytes=1452 time=54ms TTL=63
Reply from 10.15.15.254: bytes=1452 time=6ms TTL=63

Ping statistics for 10.15.15.254:
Packets: Sent = 6, Received = 6, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 4ms, Maximum = 54ms, Average = 22ms
Control-C
^C
C:>ping 10.15.15.254 -f -t -l 1453

Pinging 10.15.15.254 with 1453 bytes of data:
Reply from 10.100.5.1: Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.
Packet needs to be fragmented but DF set.

Ping statistics for 10.15.15.254:
Packets: Sent = 6, Received = 1, Lost = 5 (83% loss),
Control-C
^C

I am a bit confused, what i should do?

2

Does the Customer Wifi Router support full frames on PPPoE ?

3

There are a lot of Tp-Link, Linksys, Tenda, and a few Mikrotik, but i think, smalls home routers don’t support jumbo frames. Only the big switches. I am wrong?.

I am using ROS v6.39rc55. Could be this a problem?. The PPP was completely rewritten and it has an algorithm to select the best MTU in order CPU age.

4

PPPoE adds 8 bytes. Is the Netonix MTU of 1528 including L2 MTU?

Either way you need at least 1508 over the entire path if you want to provide 1500 to your customer.

This would mean increasing the MTU on the CCR1016 (not sure if you can do it just for a single VLAN), you may need to adjust the MTU on the Netonix up 8 bytes, not sure with that platform. You’ll need to up the wireless bridge to 1508.

Good luck.