Webfig error when adding a change MSS rule

RouterOS General
1

Hello,

i have a RouterBoard RB450G OS 5.7 and latest firmware. I was trying to add the following rule using webfig:

ip firewall mangle add out-interface=ether1 action=change-mss new-mss=1440 chain=forward protocol=tcp tcp-flags=syn

i clicked: ip->firewall->mangle->Add New->
chain: forward
protocol: 6 (tcp)
Out.Interface: ppoe-out
TCP flags: syn
Action: Change MSS
New TCP MSS: 1440
Passthrough: yes

clicking ok gives the following error message:

Couldn’t change Mangle Rule <> - tcp mss change works only on tcp syn packets (6)

So i did the same using Winbox, the rule was accepted. But when i went back to webfig and clicked the rule the TCP flags option was WRONG:

TCP flags became:
TCP flags: rst

is this a bug with webfig??

2

That rule adds to mangle fine on mine, but I’m using newer than 5.7. Try updating.

3

Thank you jandafields. i have upgraded to 5.8 and now it’s working properly.