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From: =?UTF-8?Q?Arne_Vajh=c3=b8j?= <arne@vajhoej.dk>
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Subject: Re: InetAddress.isReachable() ?
Date: Fri, 23 Oct 2020 13:14:36 -0400
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On 10/23/2020 12:50 PM, Knute Johnson wrote:
> InetAddress.isReachable() only works if I run Java as root.  Any idea 
> how to make it work with a regular user?  The docs say "A typical 
> implementation will use ICMP ECHO REQUESTs if the privilege can be 
> obtained".  I'm assuming that's why it won't work as a regular user.

Is it worth it?

The method can return false and the service you want to use
can be available (firewall blocking ICMP and Echo but not application
protocol).

The method can return true and the service you want to use
can be unavailable (OS running but server application down).

I think you would be better of connecting to the service
you want to use and handle errors there.

Arne