We moved most of our stuff to a new machine, but not our mail server of Mailman mailing list system: www.gtalug.org has address 138.197.153.212 gtalug.org has address 138.197.153.212 gtalug.org mail is handled by 0 penguin.gtalug.org. penguin.gtalug.org has address 69.164.222.247 But penguin thinks that it is gtalug.org and www.gtalug.org. and mailman thinks that it is running on gtalug.org or www.gtalug.org. Those are no longer true. What won't work: - links to the mailman web pages - mailing list archives - (maybe) access to our Wiki Even if you reference these by IP address rather than domain name, they won't work because the certificate validation will fail. This is wrong but it may be a while before it is fixed. Horrible work-around: add this line to /etc/hosts 69.164.222.247 gtalug.org www.gtalug.org But remove it as soon as you are done: it will block access to our new website. (Thank BC Ron for this suggestion.)