Foreman Maintain

I like the idea of a maintenance mode, but I think it is more user-friendly to redirect them to a status page which tells them about maintenance instead of simply disabling access.

Status page could be one internal landing page which is presented instead of Foreman just telling there is some maintenance ongoing. This would require the command to create a redirect in the webserver configuration and a static page for maintenance. This could be advanced with the command taking a comment to include in the webpage or reading the same from configuration file.

Another option would be just route the traffic to an external, already existing status page. This could be done in a similar way like disabling the access by adding firewall rules (and toggling a kernel parameter). The example below would redirect the traffic to the github status page for example. This would require the status page to have some webserver configuration which catches all URLs and redirects them to the status page.

sysctl net.ipv4.ip_forward=1
iptables -t nat -A PREROUTING -p tcp --dport 443 -j DNAT --to-destination 54.243.144.116:443
iptables -t nat -A POSTROUTING -j MASQUERADE

Both use cases are valid I think, but having both implemented would perhaps bloat the code to much, so I would be happy seeing one implemented. Or if you tell me which one is preferred I can try to implement and contributed it.