We have a Mikrotik RB 750GL and I can’t connect to it via Winbox or Http.
There is a PPTP connection (Running) between us (On Internet), That RB is PPTP Client.
Winbox stops on retrieving preferences and then disconnect. and Http webpage doesn’t load. But I can connect to it via SSH or Telnet remotely and ping it !
and a local client can connect via Winbox or Http.
also I can’t conncet to DVR (which connected to that RB).
None of these solutions work for me:
-Frameware Upgrade
-RouterOS Update
-Try L2TP Conncection
-Change MTU
-Change MRRU
-Another Winbox Version
-disable all Firewall Rules
-RB Client Reset Configuration(!)
-secure mode Winbox
-IP>Services: port and address
I need your help
It is my correct solution which I found in https://serverfault.com/questions/827051/cant-connect-to-mikrotik-via-winbox-or-http:
It may be mss problem; as in Tunnels this is most common problem. Please make sure your packages are Clamped like this:
Put these rules on top on the mangle table.
ip firewall mangle add chain=forward action=change-mss new-mss=1440 tcp-flags=syn protocol=tcp out-interface=all-ppp tcp-mss=1441-65535
ip firewall mangle add chain=forward action=change-mss new-mss=1390 tcp-flags=syn protocol=tcp in-interface=all-ppp tcp-mss=1391-65535
Here is the same rules for Input and Output (which affects mikrotik itself)
ip firewall mangle add chain=input action=change-mss new-mss=1440 tcp-flags=syn protocol=tcp out-interface=all-ppp tcp-mss=1441-65535
ip firewall mangle add chain=input action=change-mss new-mss=1390 tcp-flags=syn protocol=tcp in-interface=all-ppp tcp-mss=1391-65535
ip firewall mangle add chain=output action=change-mss new-mss=1440 tcp-flags=syn protocol=tcp out-interface=all-ppp tcp-mss=1441-65535
ip firewall mangle add chain=output action=change-mss new-mss=1390 tcp-flags=syn protocol=tcp in-interface=all-ppp tcp-mss=1391-65535