Add checks for secondary link.

Signed-off-by: Daniel Díaz <yosoy@danieldiaz.org>
Use configurable route command.

Can be set to use a remote host's route command.

Signed-off-by: Daniel Díaz <yosoy@danieldiaz.org>
Ping's latency is in seconds, not milliseconds.

Signed-off-by: Daniel Díaz <yosoy@danieldiaz.org>