The nginx_access syslog tag added in #37 (feat/emily-incident-logging)
used tag=nginx-access. nginx's syslog sink only accepts alphanumeric
characters and underscores in the tag field, so the generated
nginx.conf failed its config test on linode:
nginx: [emerg] syslog "tag" only allows alphanumeric characters
and underscore in .../nginx.conf:114
Because nginx-pre-start failed, nginx.service crash-looped until it
hit systemd's start-limit-hit and gave up entirely. Since Nextcloud is
proxied through nginx (127.0.0.1:8080, fronted by haproxy's 'next'
backend), this took next.thehellings.com down with a 503 from haproxy
(phpfpm-nextcloud/postgresql/redis backends were all healthy and
unaffected - purely an nginx config parse failure).
Fix: use an underscore (nginx_access) instead of a hyphen.
emily