[Hawkular-dev] Availability vs uptime for URL "ping"

[Thomas Heute]

In the most simplistic form of monitoring we're looking at pinging 
website and report up/down and response time from the initiator of the 
HTTP HEAD/GET

We've discussed a bit about availability vs uptime.

First question:	Do we need to distinguish ? Is it important for someone 
who wants to know if his website is accessible to really separate the 2 
concepts. (Details vs simplicity)

Second question: If we separate the 2, how do we do distinguish ? A 
suggestion:
   * HTTP Code 2xx and 3xx -> URL is up and available
   * HTTP Code 4xx -> The server may reject the request (it may not like 
bots, user entered a wrong url (should be checked upfront), or resource 
has been deleted)... Server is up, availability is unknown
   * HTTP Code 5xx -> URL is up but not available
   * Timeout -> URL is down and not available
Couldn't resolve host 'www.fffffffffefwefdwdf.com' -> Domain name is 
deleted: URL is down and not available

4xx is likely the most debatable, it's a client issue and likely needs 
either code fix or user intervention... (And we can't unfortunately 
expect servers to fully respect the codes)

Thoughts ?

Thomas