If I tick "Change TCP MSS" in the PPP profile, things work much better. E.g. YouTube videos start and skip faster.
But loading of Telegram Media like Images is very slow, e.g. take 10-15 seconds.
By adding a mangle rule into IPv6 things work well:
Code: Select all
/interface list
add comment="Clamp TCP MSS on these interfaces" name=CLAMP
/interface list member
add interface=WG1 list=CLAMP
add interface=TELEKOM list=CLAMP
/ipv6 firewall mangle
add action=change-mss chain=forward comment="Clamp TCP MSS to interface MTU" log-prefix="CLAMP FWD6" new-mss=clamp-to-pmtu out-interface-list=CLAMP passthrough=yes \
protocol=tcp tcp-flags=syn
add action=change-mss chain=forward in-interface-list=CLAMP log-prefix="CLAMP FWD6" new-mss=clamp-to-pmtu passthrough=yes protocol=tcp tcp-flags=syn
Finally, I have the feeling that the "Change TCP MSS" option in the PPP profiles only works on IPv4.
Can somebody confirm this?