LOL. I just went though this the other day. my site was intermittently non-accessible. DNS was the last thing I thought it was until I ran a crawler on my site and spotted some 404 errors. Found that my non-www. url was pointed at the wrong IP and I forgot to update it when I transfered my domain to a new host.
whoa whoa whoa.. slow down! you dont just leap to "It's DNS"... you have to try to blame everything else first before you get to DNS. it's like foreplay!
(Or, as I recently encountered, it can also be a McAfee corporate firewall trying to be helpful by showing a download progress bar in place of an HTTP SSE stream. I was sure that was being caused by MTU, but alas no.)
I had _just_ pushed an updated actions workflow, saw that it began to run, and noticed that my entire repository was 404-ing. Not gonna point fingers, but uh, sorry everybody.
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