Originally Posted By: andym
BTW, where does it show your MTU on the config page? (I assume you mean the page on clueless?).

Yeah. Its the page on clueless that you're thinking of. Its the same place you set LCPFix. It is just above where the log at the bottom of the page is.

Start 26 Dec 13:42:22 Latest Today 16:00:00 Session 0000000000000000000000 a.gormless Login xxx@q.1 Bytes 493M/10.7G Pkts 4.61M/7.79M 26.0Mb/s mru1500

My line had LCPFix turned on already and I can't remember when or what turned it on. I had to configure another Mikrotik on FTTC for somebody else and it wouldn't work at all for 1500 MTU unless I turned on LCPFix. The Firebrick 6000 manual mentions about BT sometimes not sending the correct value and there being the LCPFix option to make it work properly.

You can see what BT is telling A&A in the RADIUS log page for your line on clueless.

Dec 26 13:42:23 newclueless radius-auth: BBEU00000000 BT Accept x.x.x.x x.x.x.x xxx@q.1 a.gormless LCP-restart Premium txrate=26000000bps linerate=30478000/1000 MTU=1492
Dec 26 13:42:31 newclueless radius-acct: BBEU00000000 Start xxx@q.1 x.x.x.x MRU=1500 linerate=26000000/1000 I/F=00:00:00:00:00:00:00:07