I'm attempting to use Net::OpenSSH to connect to a remote linux host and execute a tcpdump command in the background while then executing a ping, stopping the tcpdump and printing the result to the screen. I realize that each command runs in it's own session but I thought I could use nohup and & to create a background process that wouldn't exit. I know that Expect can be used for a more interactive process but I was wondering what the best/recommended way to do this would be (without using Expect).
#!/usr/bin/perl

use strict;
use warnings;
use Data::Dumper;
use Net::OpenSSH;

my $username = 'username';
my $password = 'password';
my $params;
my $session_obj;

$session_obj = Net::OpenSSH->new("10.2.200.12", user => $username, pas
+sword => $password, strict_mode => 0,master_opts => [ -o => "StrictHo
+stKeyChecking=no"]);
$session_obj->error and die "ssh failed: " . $session_obj->error;
print Dumper($session_obj);
# Each command runs in its own session
my ($out,$err) = $session_obj->capture2('nohup /usr/sbin/tcpdump -i et
+h1 -s 1500 -w /tmp/tmp.pcap &');
print "THE OUT IS $out\nTHE ERROR IS $err\n";
($out,$err) = $session_obj->capture2('ping -I eth1 -c 3 192.168.107.25
+4');
print "THE OUT IS $out\nTHE ERROR IS $err\n";
($out,$err) = $session_obj->capture2('killall tcpdump');
print "THE OUT IS $out\nTHE ERROR IS $err\n";
($out,$err) = $session_obj->capture2('tcpdump -r /tmp/tmp.pcap');
print "THE OUT IS $out\nTHE ERROR IS $err\n";

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In reply to Net::OpenSSH and background process by josh803316

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