Systemd

Noticed these lines in journalctl when nginx didn’t start after a reboot:

Dec 10 17:43:30 mail1 nginx[3485]: nginx: [warn] "ssl_stapling" ignored, host not found in OCSP responder "ocsp.int-x3.letsencrypt.org" in the certificate "/etc/letsencrypt/live/www.example.com/fullchain.pem"
Dec 10 17:43:30 mail1 nginx[3485]: nginx: [emerg] bind() to [<IPv6 address>]:80 failed (99: Cannot assign requested address)
Dec 10 17:43:30 mail1 nginx[3485]: nginx: configuration file /etc/nginx/nginx.conf test failed
Dec 10 17:43:30 mail1 systemd[1]: nginx.service: Control process exited, code=exited status=1
Dec 10 17:43:30 mail1 systemd[1]: nginx.service: Unit entered failed state.
Dec 10 17:43:30 mail1 systemd[1]: nginx.service: Failed with result 'exit-code'.
Dec 10 17:52:35 mail1 systemd[1]: nginx.service: Failed to read PID from file /run/nginx.pid: Invalid argument

Hmmm…

I ran into a problem with NGINX failing to start on boot/reboot on my Debian 8 (Jessie) server. After reviewing what seemed like a hundred sites to try to find a fix, I stumbled across one solution that worked, but was incredibly inelegant. This was to add:

RestartSec=30s
Restart=on-failure

to nginx.service in the [Service] section using the override.conf. It worked but didn’t fix the underlying problem.

A quick look using journalctl -u nginx showed that the service was failing because the IPv6 address hadn’t been assigned to the network adaptor yet. This caused nginx to fail because it couldn’t bind to the IPv6 port. Here are the log lines: