Not a very descriptive error, is it?
bind(0.0.0.0) failed (22: Invalid argument) while connecting to upstream
Let me tell you, this is caused (or at least in the setup I was tasked with fixing it was) by proxy_bind directive. In the case of the error above, it was set to 0.0.0.0.
But why does it cause the error? Because the upstream is or resolves to an IPv6 address. And that’s incompatible with a connection coming from 0.0.0.0 (i.e., any IPv4 address available)! In most cases, you don’t actually need the proxy_bind directive at all, so remove it, probably you just copy-pasted it anyway. ;·)
For more details, you might want to read this bugreport.
HEADS-UP! If you’re tempted to “just disable IPv6 altogether,” be aware that the world is shifting to IPv6-only. So disabling IPv4 altogether seems like the better option to me (in that case be sure to let me know, I’ll add your website to the list! :·)).
BTW, if you want to keep using nginx instead of Apache, I suggest switching to freenginx. Read more about it in its announcement.
Tagged with: nginx
Written: 2024-03-19