![Linux Uptime](https://i2.wp.com/www.stevejenkins.com/blog/wp-content/uploads/2012/10/uptime-pic.jpg?resize=570%2C300&ssl=1)
After upgrading from Nagios 4.0 to 4.0.1, I attempted to manually reschedule a check of all services on a particular host, I received the following error: Error: Could not open command file ‘/usr/local/nagios/var/rw/nagios.cmd’ for update! The source of the problem turned out to be a permissions issue with the nagios.cmd […]