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From: ejm@riscit.NOC.Vitalink.COM (Erik J. Murrey)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: Testing if a host is up
Message-ID: <46@prang.TEST.Vitalink.COM>
Date: 19 Feb 91 22:10:18 GMT
References: <1991Feb16.041439.1038@Think.COM> <529@trux.UUCP>
Sender: usenet@prang.TEST.Vitalink.COM
Reply-To: ejm@riscit.NOC.Vitalink.COM (Erik J. Murrey)
Lines: 25
Nntp-Posting-Host: riscit.noc.vitalink.com

In article <1991Feb16.041439.1038@Think.COM>, barmar@think.com (Barry
Margolin) writes:
> In article <529@trux.UUCP> car@trux.UUCP (Chris Rende) writes:
> >I need a way to put a test ahead of the FTP that will determine whether
> >or not the other host is "up".
> >Here is what I have so far:
> 
> ># hostup - Written 01/30/91 by Chris Rende
> [Script omitted]
> 
> Except for the exact text of the message printed, the ping command does
> exactly what your shell script does.  It returns 0 status if the host is
> up, and non-zero when the host is down.
> 

Also, more as a heads up...  Some SLIP-ed or PPP-ed hosts have ICMP
messages filetered out specifically to prevent pings from clogging
low-speed links.  Although I don't necessarily agree with this, I do
see that the SLIP/PPP code allows this.

... Erik
---
Erik J. Murrey
Vitalink Communications NOC
ejm@NOC.Vitalink.COM	...!uunet!NOC.Vitalink.COM!ejm