Firewall Mangle rule order will change unexpectedly

Mine is PPPoE cleint. There are 2 mangle rules “change MSS” at the top. Sometimes, for unknown reason, they were moved to the bottom.
Without them, some of the web pages can not be visited. When this happened, I have to move them to the top manually.
Is it a bug? Is there anyway to ALWAYS stick them at the top?


Normal





Few days later

I have noticed this too. Took me a while to figure out what had happened because it was working just fine.
( RB433AH ROS 5.2)

You should raise a bug report with support@mikrotik.com.

Those mangle rules that change position are automatically created ones for PPP interfaces.

Mine always stays at the bottom of my firewall table. I’m using an Intel x86 machine with ROS v5.2, and PPPoE & PPTP clients.

I haven’t tried moving those dynamic/automatically created ‘change MSS’ rules to the top though.
Perhaps you should try to create those ‘Change MSS’ rules manually?

I did that, but it still happened. I’ve upgraded to V5.4, no help at all. A bug report was sent, hope they can fix it.

Phuang3 Hello, I have exactly the same problem. Have you received a reply from mikrotik about it?

Same issue does exist in 6.12 temporary solved it by creating manual change MSS rules for my pppoe interface.

If there are no other mangle rules in the froward chain, the position of those rules doesn’t matter and they will work no matter what.
That’s why they usually work.
One can do packet marking in the prerouting chain instead of forward, so they don’t interfere.

Same problem spotted in 6.19

I have other mangle rules that don’t have passthrough marked, so when these drop to the bottom they don’t get reached…

I see that my routers have 2 Change MSS rules that apply to all PPP interfaces in 6.19, so I’d guess that this problem is solved for me.

@Sinbad:
Do you have a reason why you cannot simply add those 2 Change MSS rules manually and place them first with ROS 6.19?