Hard on the heels of the DDoS attack on Saturday, this site was inaccessible for much of Sunday. (In fact I still can’t get to it from my Mac back in my apartment.) Put it all down to planned work, bad luck on Steve’s part, and bad planning on mine.
For a variety of reasons, Steve decided to move grommit to a new co-location center. The move was scheduled for Sunday afternoon (PST), and we all had plenty of time to prepare for it. As Steve describes in his blog, the move itself went OK, but he was caught out by a couple of bad Solaris patches that he decided to install. However by about 9 o’clock everything was up and running.
Everything except geoffarnold.com.
I’d forgotten that our DNS address would be changing, and at 9 o’clock I was enjoying the Tallis Scholars‘ concert at the Town Hall when I received an email from Steve reminding me to update my DNS configuration. After the concert, I headed home, worrying as I went about whether I could remember my login for everydns.net (and hoping that my on-file email address wasn’t the geoffarnold.com one – or, even worse, my old Sun address!). Fortunately I was able to log in and make the changes without any difficulties.
So how come I still can’t access geoffarnold.com from home? Put it down to lack of foresight on my part. The DNS “A” (address) record for geoffarnold.com, the bit that tells other computers what my IP address is, has a TTL (time to live) of 86400. That’s 24 hours, expressed as seconds. So any DNS server that retrieved my address less than 24 hours before I made the change is perfectly entitled to use that copy until the TTL expires. This means that everybody should get the new address in about 14 hours from now. If I’d been thinking ahead, I would have logged in to everydns a couple of days ago and adjusted the TTL down to, say 3600 (one hour). That way, when I actually changed the address, I could be sure that the stale information would be gone within an hour.
Next time, next time.