27/08/2021, 1:54 pm
I run my own mail server, I have done for a few years. Before I moved I was with Virgin and although I didn't have a fixed IP address, it only changed about three times in nearly 20 years, as whenever I upgraded my router, I always cloned the MAC from the previous one so it always looked like the same router was connecting. Since the move into a more rural area I'm outside of Virgin's service area, so I had to go with BT. They don't supply static IPs on home connections, just as an option for business (= more expensive + payment for the static IP), so I'm using a DDNS service set up in the router to keep everything in line.
This is fine most of the time until one day I found my outbound emails were failing. It turns out the IP address that had been assigned this time was on a blocklist so gmail and others were rejecting my emails. Problem with the BT service is that although my router is on 24/7, it can still get reassigned a new IP address at will. When the current lease expires it rarely gets renewed with the same one, so it is entirely random - they are all from a wild variation of IP blocks, so there's no telling what I will get next time or who had it before me or how they used it.
This is fine most of the time until one day I found my outbound emails were failing. It turns out the IP address that had been assigned this time was on a blocklist so gmail and others were rejecting my emails. Problem with the BT service is that although my router is on 24/7, it can still get reassigned a new IP address at will. When the current lease expires it rarely gets renewed with the same one, so it is entirely random - they are all from a wild variation of IP blocks, so there's no telling what I will get next time or who had it before me or how they used it.
Acorn since 1981, RISC OS since 1988