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$NetBSD: MESSAGE,v 1.2 2013/02/18 20:32:09 imil Exp $

Consider adding something like following lines to /etc/newsyslog.conf:

/var/log/nginx/access.log nginx:nginx 640 7 * 24 Z  /var/run/nginx.pid SIGUSR1
/var/log/nginx/error.log  nginx:nginx 640 7 * 24 Z  /var/run/nginx.pid SIGUSR1

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