Question To Mikrotik Team

Hi everyone,
I had a lot of problems with RB133 boards, When we buy them the ROS was 3.0.
After that there were ne versions, and I upgraded them to 3.1 , 3.2, 3.3 … to 3.6,
After the last upgrade (to 3.6) My PPTP and PPPOE clients could not connect to internet. They connected to NAS (2.9.51)
but there was no TCP traffic, they have ping to all servers, but there was no HTTP, no ICQ.
Who can explain why?
After the downgrade to 3.5 then 3.4 … , 3.1, and at last 2.9.51, they began to work.
Where did I make a mistake, or there was something wrong with the Routerboard

They connected to NAS (2.9.51)
but there was no TCP traffic, they have ping to all servers, but there was no HTTP, no ICQ.

Probably there are problems with “path MTU discovery” and you need to adjust mss for packets going over PPPoE link,
http://www.mikrotik.com/testdocs/ros/2.9/interface/pppoe_content.php#5.28.8

Where did I make a mistake, or there was something wrong with the Routerboard

No, this problem certainly is not RotuerBOARD specific.

Sergejs Thanks For Reply.
Now I have put the default settings for the PPPoE Server,
But the sameproblem I have on 2.9.51.

Do you have change-mss rule enabled?
Make sure that you have decreased max-mtu and max-mru [accordingly to documentation or even with lower values]
and change-tcp-mss=yes for used PPPoE profile.

Sorry to jump in, Sergej but wasn’t there problems with tcp-mss=yes?, i remember topic about that and everybody said that chang-tcp-mss should be no and that the best is to put separate firewall rules to change mss.

I’m Lost

B/R
Michal