On a Fedora 22 box I have in rc.local: 
#!/bin/sh
/var/tmp/DiaPixie.sh  &
/var/tmp/DiaPixie.pl  &
exit 0

[download]
And the scripts contain: 
#!/bin/sh
while : ; do
  r=`wget -O - "http://myip.dtdns.com" 2>/dev/null | head -1`
  logger -t DiaPixie.sh "Got: $r"
  sleep 180
done

[download]
And: 
#!/usr/bin/env perl
use strict;
use warnings;
use LWP::Simple;
use Sys::Syslog;
while (1) {
  if( defined(my $Address=get("http://myip.dtdns.com")) ) {
    syslog("info","Got: $Address")
  }
  else {
    syslog("info","Got: "        )
  }
  sleep 180
}

[download]
So I'd expect them both to generate similar messages. But the shell script fails to get an address the first time (as we might expect), and the Perl script (when initiated from rc.local) fails every time. What's going on here?

In reply to Systemd Network Problem by Anonymous Monk

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