Question

What is the difference between webclient and httpclient?

Answer 1

Ping sends ICMP echo requests to the target machine. Many machines will not respond to these requests because firewalls. So this is an unreliable means of checking if a machine is running, let alone running the service you're interested in connecting to.

The best way to check if a service is running is to try and use it (without any kind of pre-check) in the way that the service provider intends you to use it. If it doesn't work, then you can safely say that the service is down.

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