Groups > comp.lang.java.programmer > #39639

Re: InetAddress.isReachable() ?

Path	csiph.com!eternal-september.org!feeder.eternal-september.org!reader02.eternal-september.org!.POSTED!not-for-mail
From	Knute Johnson <knute2020@585ranch.com>
Newsgroups	comp.lang.java.programmer
Subject	Re: InetAddress.isReachable() ?
Date	Fri, 23 Oct 2020 18:10:09 -0500
Organization	A noiseless patient Spider
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On 10/23/20 12:14 PM, Arne Vajhøj wrote:
> 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?

Yes

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

No firewalls there.

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

No service to connect to.  Just want to see if there is a path to the 
router.

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

Again no service to connect to.

It's an internal network and I'm fielding calls all the time that 'we 
aren't getting updates to our data'.  If I can ask is the little box 
green or red I'll know with some certainty the status of their network 
connection.  I'm 1600 km from the site so I can't just pop over for a 
look see.  I can't ask them to ping the router, that's a step too far. 
The network service at the remote sites is interrupted on a fairly 
regular basis.

So yes I would really like to figure out how to make this work is it is 
possible.

Thread

InetAddress.isReachable() ? Knute Johnson <knute2020@585ranch.com> - 2020-10-23 11:50 -0500
  Re: InetAddress.isReachable() ? Arne Vajhøj <arne@vajhoej.dk> - 2020-10-23 13:14 -0400
    Re: InetAddress.isReachable() ? Knute Johnson <knute2020@585ranch.com> - 2020-10-23 18:10 -0500
      Re: InetAddress.isReachable() ? Arne Vajhøj <arne@vajhoej.dk> - 2020-10-23 20:30 -0400
        Re: InetAddress.isReachable() ? Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2020-10-23 19:38 -0500
          Re: InetAddress.isReachable() ? Martin Gregorie <martin@mydomain.invalid> - 2020-10-24 11:45 +0000
            Re: InetAddress.isReachable() ? Knute Johnson <nospam@rabbitbrush.frazmtn.com> - 2020-10-29 15:23 -0500
              Re: InetAddress.isReachable() ? Martin Gregorie <martin@mydomain.invalid> - 2020-10-29 21:36 +0000
              Re: InetAddress.isReachable() ? Arne Vajhøj <arne@vajhoej.dk> - 2020-10-29 21:47 -0400
                Re: InetAddress.isReachable() ? Knute Johnson <knute2020@585ranch.com> - 2020-11-01 10:30 -0600

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