I have had a M0n0wall site-to-site IPsec VPN working for several months on a static IP via an ADSL router.
We've just switched to a fibre (FTTC) connection, and M0n0wall has now been configured to connect to the ISP using PPPoE via a VDSL modem. This presumably means our PPP server is assigning our (new, different) static IP (and IP range). All other settings are unchanged, but the IPsec tunnel now no longer comes up.
racoon: ERROR: none message must be encrypted and:
racoon: ERROR: phase1 negotiation failed due to time up. in the logs, but all within a single second.
There's some suggestion this may be to do with the difference between routed DSL and the way VDSL works, but nothing clear.
Any ideas why VDSL might get in the way of IPsec?