Question : Net Telnet Cisco > script quits when host is non-responsive

Hello,

I'm using Net::Telnet::Cisco to update configs on multiple Cisco routers (all are 1841 model). The script reads from a CSV file that has the router IP, and commands to be entered. The script runs fine unless a router does not respond to telnet in which case the script does not continue to execute. I would like the script to skip an unresponsive host and write the unresponsive host to a file, then continue to the next host in the CSV file. Also, after a reload command is entered for a particular router, the script does not continue to execute. Any help would be greatly appreciated.

Example of my perl script:

#!/usr/bin/perl
#

use Net::Telnet::Cisco;

#Username for router
print "Enter username\n";
$user = ;
chomp($user);

#password for router
print "Enter password\n";
$pass = ;
chomp($pass);

#CSV file with router IP and commands
print "Enter filename\n";
$State = ;
chomp($State);

open (INDB, "./$State.csv") or
      die "cannot find file";

#reads every line in CSV file
while ()
      {
$SiteData = $_;
chomp ($SiteData);
($HostNumber, $loopback, $copytftpst, $tftpserver, $configpath, $deststcfg, $reload) =

split (/,/, $SiteData);

my $CISCO_IP = "$loopback";
my $username = "$user";
my $password = "$pass";
my $enable_password = "$pass";

my $session = Net::Telnet::Cisco->new(Host => $CISCO_IP, Input_log=> "$SiteNumber.txt", Timeout=> '120');

$session->login($username, $password);

my @output = "";
my @host = "";

# Enable mode
if ($session->enable($enable_password) )
{
@output = $session->cmd('show privilege');
@host = $session->cmd('sho run | include hostname');
print "@output for @host $loopback\n";
}
else
{
warn "Can't enable: " . $session->errmsg;
}

$session->cmd("$copytftpst\n$tftpserver\n$configpath\n$deststcfg\n$reload");
$session->close;

      }

Example of CSV file with hosts/commands:

rtr1, 10.1.1.1, copy tftp startup-config, 10.0.0.1, rtr1/rtr1.1800.txt, startup-config, reload
rtr2, 10.2.2.2, copy tftp startup-config, 10.0.0.1, rtr2/rtr2.1800.txt, startup-config, reload

Answer : Net Telnet Cisco > script quits when host is non-responsive

In the code you posted, line 36 is
my $enable_password = "$pass";
which is not causing the problem. I'll assume that your line 36 is:
my $session = Net::Telnet::Cisco->new(Host => $CISCO_IP, Input_log=> "$SiteNumber.txt", Timeout=> '120');

If this is the case, try this:

                       
             ...
my $enable_password = "$pass";
 
my $session;
eval {
    $session = Net::Telnet::Cisco->new(Host => $CISCO_IP, Input_log=> "$SiteNumber.txt", Timeout=> '120');
}
if($@) {
    warn "Could not connect to $CISCO_IP: $@\n";
    next;
}
 
$session->login($username, $password);
...

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