A perl script which detects running nodes in networks. It also can get MIB. It is necessary to specify conf file(detectNodes.conf) and binary of Snmpwalk.java.

detectNodes.conf

IPaddr: 192.168.0.1-20
IPaddr: 192.168.0.30-40
oid: .1.3.6.1.2.1.1.3
com: public

detectNodes.pl

use strict;
use warnings;
use Net::Ping;

#----------------------------
# Global defs.
#----------------------------
my %CONF;
my $SNMP_WALK_CMD = 'Snmpwalk';

#----------------------------
# Main
#----------------------------
print "### detectNodes Starts. ###\n";

%CONF = readConfFile('detectNodes.conf');
my @targetIpAddrs = makeTargetIpAddrList($CONF{'ipAddrRanges'});
my @aliveNodes = execPing(@targetIpAddrs);
execSnmpwalk(@aliveNodes);

print "### detectNodes Ends. ###\n";

#----------------------------
# sub functions
#----------------------------
sub readConfFile{
  my $confFile = shift;
  open(FILE, $confFile) or die "$!";
  
  my %conf;
  my @ipAddrRanges;
  while (my $line = <FILE>) {
    if($line =~ /^\s*#/){
      next;
    }
    chomp($line);
    
    if($line =~ /IPaddr:/){
      my @work = split(/:/, $line);
      push(@ipAddrRanges, $work[1]);
    }
    if($line =~ /oid:/){
      my @work = split(/:/, $line);
      $conf{'oid'} = $work[1];
    }
    if($line =~ /com:/){
      my @work = split(/:/, $line);
      $conf{'com'} = $work[1];
    }
  }
  $conf{'ipAddrRanges'} = \@ipAddrRanges;
  close(FILE);
  return %conf;
}

sub makeTargetIpAddrList{
  my $ref_ipAddrRanges = shift;
  my @ipAddrRanges = @$ref_ipAddrRanges;
  my @targetIpAddrs;
  
  foreach my $ipAddrRange (@ipAddrRanges){
    my @octets = split(/\./, $ipAddrRange);
    my @fourthOctetRange = split(/-/, $octets[3]);
    my $startIP = $fourthOctetRange[0];
    my $endIP = $fourthOctetRange[1];
    
    for (my $i = $startIP;  $i <= $endIP;  $i++){
      my $targetIpAddr = $octets[0]."\.".$octets[1]."\.".$octets[2]."\.".$i;
      # Remove spaces for ping execution.
      $targetIpAddr =~ s/^\s*(.*?)\s*$/$1/; 
      push(@targetIpAddrs, $targetIpAddr);
    }
  }
  return @targetIpAddrs;
}

sub execPing{
  my @ipAddrs = @_;
  my @aliveNodes;
  my @downNodes;
  
  my $pingTimeout=2;
  my $pingObj = Net::Ping->new("icmp"); # cmd is need to be started as admin for ping execution.
  
  print("Exec ping...\n");
  foreach my $ipAddr (@ipAddrs){
    if($pingObj->ping($ipAddr, $pingTimeout)){
      print "$ipAddr is running.\n";
      push(@aliveNodes, $ipAddr);
    }
    else{
      push(@downNodes, $ipAddr);
    }
  }
  $pingObj->close();
  print("\n");
  return @aliveNodes;
}

sub execSnmpwalk{
  my @aliveNodes = @_;
  print("Exec snmpwalk...\n");
  foreach my $aliveNode (@aliveNodes){
    print(qq[------- Execute "$SNMP_WALK_CMD -c $CONF{'com'} $aliveNode $CONF{'oid'}" -------\n]);
    #system("$SNMP_WALK_CMD -c $CONF{'com'} $aliveNode $CONF{'oid'}");
    system("java -cp lib/snmp4j-2.1.0.jar;. $SNMP_WALK_CMD -c $CONF{'com'} $aliveNode $CONF{'oid'}");
    print("\n");
  }
}