Greetings Wise Monks,

I am having a very strange problem. I have a script which uses LWP::UserAgent to connect to web pages. It has functioned properly for quite some time, but started failing last week, and LWP::UserAgent reports a 500 error. From this node, I learned that a 500 error does not necessarily come from the server, and that LWP will report 500 even if it does not reach the server. Following a great suggestion I got from this node, I Data::Dumpered the value returned by $ua->request(), discovering that I am getting the message:

Can't connect to <domain>:80 (Bad Hostname '<domain>')

This only happens when the code is run as a CGI.
It works properly from command line, whether as root or the apache user. This script is on several servers, and is functioning properly on one of them, failing on most. I have compared the code between the working server and the rest, and found no differences. LWP::UserAgent is the same on both (2.003) and so is HTTP::Request (1.30). Both machines are running FreeBSD 4.8, and /etc/resolv.conf is the same for both. Our sysadmins made no recent changes to these servers.

Update: Using an IP address instead of the domain name works. Also, forgot to mention that from command line, I can ping and ssh to other domains. Also, mod_perl is involved here.

The code does not seem to be the issue here, but I here is the relevant snippet anyway (not mine): 
   my $qurl = 'legitmate url (tested -- fails for many)';
   my $uasnd = new HTTP::Request ('GET', $qurl);
   $uasnd->header('Accept' => 'text/html');
   my $res = $ua->request($uasnd);
   use Data::Dumper;
   print STDERR "RES:  ".Dumper( $res )."\n";
   my $code= $res->code;  # RETURNS 500
   my $content= $res->content;  # NADA

[download]
Output is: 
RES:  $VAR1 = bless( {
        '_content' => '',
        '_rc' => 500,
        '_headers' => bless( {
                                'client-date' => 'Wed, 03 Mar 2004 17:
+37:09 GMT'
                             }, 'HTTP::Headers' ),
        '_msg' => 'Can\'t connect to domainname.net:80 (Bad hostname \
+'domainname.net\')',
        '_request' => bless( {
                                '_content' => '',
                                '_uri' => bless( do{\(my $o = 'http://
+domainname.net/?param1=1&param2=2')}, 'URI::http' ),
                                '_headers' => bless( {
                                                      'user-agent' => 
+'libwww-perl/5.69',
                                                      'accept' => 'tex
+t/html'
                                                     }, 'HTTP::Headers
+' ),
                                '_method' => 'GET'
                             }, 'HTTP::Request' )
      }, 'HTTP::Response' );

[download]
Something tells me this is going to be something stupid that I have forgotten, but I have asked several others about this. Anyone had a similar experience or know what this could be? As always, your time and assistance is much appreciated.

bassplayer

In reply to LWP::UserAgent connection problem as CGI by bassplayer

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