Feature Request: Support non-HTTP (ICMP, TCP connect) measurements

[eric]

There are a lot of cases where I would like to monitor basic connectivity via ICMP (I am currently using smokeping with fping).

Are other protocols something you're considering doing?

[gorsuch]

That's a fantastic idea, and yes, sounds wonderful to me. Once I finish up on #6, we can investigate how we might extend the interfaces (if necessary) to handle other protocols.

It would also be cool if we could express these definitions as URLs (icmp://192.168.1.1, tcp://192.168.1.1:10000, etc).

[eric]

Another fun trick/hack I've thought about is testing the time it takes to get a "Connection Refused" response back from a server.

The thing that's nice about ICMP is that it doesn't require a service to be running and listening to get a response. Unfortunately, sending ICMP requires the process be run by root (or otherwise setuid as root).

I have had an idea that if you try to open a TCP connection to a port that isn't listening and time how long it takes to get the "Connection Refused" back, it should give you reasonable network timing without using ICMP.