Windows – Mongo forcing a log rotation on Windows

I believe it's the content of the state file, which is my case is /var/lib/logrotate.status. Each file has one line, which is the date on which it was last rotated; if you run logrotate on such a date that a given file is due for rotation, given the number of days between current date and the date in the file (1 for daily, 7 for weekly, etc.), the file will be rotated.

logrotate doesn't seem to care at what time of day it's run; even if it usually runs at 2355, if you were to run it at 0130 instead, it would still rotate files marked daily and last done yesterday; but having done so it would put today's date into the state file (against any rotated files), so a second run at 2355 would do nothing.

It has become a sort-of informal semi-standard among Unix daemons that they flush and/or rotate their log files, when you send them a hangup signal (SIGHUP). Nginx doesn't follow this convention to the letter, but it responds to the USR1 signal the same way, as is documented on the Nginx website under the title Log Rotation.

So, you could try something like

kill -s USR1 `pidof nginx`