check_ssh_login plugin incorrectly handles configured timeout

[atc0005]

Overview

By default the plugin is configured with a 10 seconds timeout intended to prevent connection attempts from hanging.

Today one the systems monitored by a Nagios XI system I manage went down and Nagios XI ended up forcefully terminating the service check after 300.01 seconds (300s global timeout value).

When I manually tested against a separate, confirmed down system I observed fast failure responses.

References

• Add custom timeout support #31
• https://stackoverflow.com/questions/64194870/getting-timeout-value-from-gos-context
• https://stackoverflow.com/questions/46279205/how-to-abort-a-net-dial-call-in-go

[atc0005]

After a brief review of the plugin code I found where the timeout is applied inconsistently. In particular, the net.Dial call lacks any configured timeout.

The supported timeout is supplied to other portions of the codebase as intended.

I should go back and ensure that a context is used as I believe I originally intended. This should make it easier to propagate the intended timeout value consistently.