You could get ARP info via Telnet or Web, but my preference is to get it via SNMP. Here is some code you can plagerize - lot of stuf you probably won't use, and you will need to remove database references, but it should get you a lot more than you wanted.

Sorry - Not the cleanest code -- I was still learning SNMP.

Concentrate on "sub ARPtable". 

#######################################################
## Bridgemac.pl
## Queries the main routers for the ARP table
## Queries E7 and Vertical horizon switches for 
## their Forwarding database (All Mac addresses).
## Stores info collected into the ARP table of the
## Hardware Database.
## The router ARP entries are queried for MAC <=> IP
## The Switch table gives Mac <=> Port/Switch info.
## All Equipment queries use SNMP.
##
## This is intended to run periodically as a scheduled
## job that updates the database.
## Database queries are done externally (Via web app)
## By Vijay Anand , March 2003 -Overhauled Sept2003
###########################################################
use strict;
use Net::SNMP qw(:snmp);
use DBInterface; # Vijay's homegrown DB module for Hardware Db

my $session;
my %SysInfo; # Contains {MaxPorts, manufacturer etc..};
my @FrontPorts; # Index by Maxports, gives last front-panel port numbe
+r

my @hosts=qw( 
  ### Enter a list of Switch IP addresses here ......<<<<<
               );
#########################################
### Program Starts #############

my $DB = DBInterface->new();
Query_Router_ARP_And_Update_DB('**IP address of ROUTER***');


foreach (@hosts){
        Query_Switch_And_Update_DB($_);
}
# ARP tables may have changed or be incomplete
# So run them again
Query_Router_ARP_And_Update_DB('**IP address of ROUTER**');
print "--Closing DB--\n";
$DB = undef; # Close
print "--end--\n";
###########################################
sub Query_Router_ARP_And_Update_DB{
  &connect( host =>  shift,
           comm => shift || 'public');
  my $ARPTable = ARPtable();
  print "Got " . %{$ARPTable} . " arp entries from $session->{Hostname
+}\n";
  my %myrec;
  $DB->{REC} = \%myrec;
  ##$DB->verbose(1);
  foreach (sort keys %$ARPTable){
     #print "   $ARPTable->{$_} : $_\n";
      $myrec{Mac} =$ARPTable->{$_};
      $myrec{IP}  = $_;
      $DB->Write_Rec();
  }

}
###########################################
sub Query_Switch_And_Update_DB{
  $session = undef;
  %SysInfo = {};
  &connect( host => shift,
           comm => shift || 'public');
  &Initial_Params;
  print "Front panel ports = $FrontPorts[$SysInfo{MaxPorts}]\n";
  my ($fdb, $PortName) = &queryfdb();


  # First, save this switch's Primary address
  my %myrec = (
        Mac => $SysInfo{Mac} ,
            IP => $SysInfo{Host} ,
            User => '' ,
            HostName =>$SysInfo{Host} ,
            SwitchName => $SysInfo{Model} ,
            SwitchPortIdx => 0,
            SwitchPortName => 'Internal',
            HostType => 'Switch' ,
            Notes => $SysInfo{Manufacturer} ,
            UpstreamID =>''
            );
  $DB->{REC} = \%myrec;
  my $SwitchRecId= $DB->Write_Rec();

  for (my $port = 1;$port < @{$fdb}; $port++){
          my $macs = $fdb->[$port] or next;
          $port > $FrontPorts[$SysInfo{MaxPorts}] and next; # Dont sho
+w uplinks
          print "PORT $port $PortName->[$port] Macs= @$macs\n";
          # $PortName->[$port] =~s/\s/_/g; # Db does not like spaces ?
          foreach (@$macs){
              %myrec =(
                    Mac=> $_,
                    IP=> '' ,
                    User=> '' ,
                    HostName =>'' ,
                    SwitchName => $SysInfo{Host} ,
                    SwitchPortIdx => $port,
                   ## SwitchPortName => $PortName->[$port],
                    HostType => '' ,
                    Notes => '' ,
                    UpstreamID =>$SwitchRecId
                    );
            $DB->Write_Rec();
          }#End For Each
  }#End For
} # End Main Loop
#################################################################
sub connect {
   my %cla = @_;
   $cla{comm} = "public" unless exists $cla{comm};
   $session = Net::SNMP->session(Hostname  => $cla{host},
                                 Community => $cla{comm});
   if (!defined($session)) {
      die "**SNMP Connect ERROR for %s: %s.\n",$_;
   }
}
#################################################################
sub Initial_Params{
    my    $sysUpTime                       ='1.3.6.1.2.1.1.3.0';
    my    $sysDescr                        =qq(1.3.6.1.2.1.1.1.0); #sy
+stem.sysDescr.0
    my    $ifNumber                        = qq(1.3.6.1.2.1.2.1.0);
    my    $dot1dStpTopChanges              =qq(1.3.6.1.2.1.17.2.4.0);
    my    $dot1dStpDesignatedRoot          =qq(1.3.6.1.2.1.17.2.5.0);
    my    $dot1dStpPortTable               =qq(1.3.6.1.2.1.17.2.15);
    my    $dot1dBaseNumPorts               =qq(1.3.6.1.2.1.17.1.2.0);
    my    $dot1dStpTimeSinceTopologyChange =qq(1.3.6.1.2.1.17.2.3.0);
    my    $dot1dBaseBridgeAddress          =qq(1.3.6.1.2.1.17.1.1.0);

    # Initialize Frontports to be the same as that reported
    for (my $i = 0; $i < 1024; $i++){
        $FrontPorts[$i] = 999999; # View ALL ports, by default
    }
    # Now do the special cases ..
    $FrontPorts[26] = 24; # Vh2402
    $FrontPorts[61] = 48; # 6h302-48
    $FrontPorts[19] = 06; # 6G306-06

    my $result = $session->get_request(
               -varbindlist => [$sysUpTime, $dot1dStpTopChanges, $sysD
+escr,
                              $dot1dStpDesignatedRoot, $dot1dBaseNumPo
+rts,
                              $dot1dStpTimeSinceTopologyChange,
                              $dot1dBaseBridgeAddress,$ifNumber  ]);

      if (!defined($result)) {
         die ("ERROR in initial request: %s.\n", $session->error);
      }

      #print( $session->hostname . " " .
      #      &showinfo($session,"TC_count",$dot1dStpTopChanges) .
      #      &showinfo($session,"rootBridge",$dot1dStpDesignatedRoot) 
+.
      #      &showinfo($session,"ports",$dot1dBaseNumPorts)   .
      #      &showinfo($session,"TC_Time",$dot1dStpTimeSinceTopologyCh
+ange) .
      #      &showinfo($session,"This-BridgeMac", $dot1dBaseBridgeAddr
+ess) .
      #      &showinfo($session,"This-Bridge", $sysDescr) .
      #        "\n"
      #      );
       $SysInfo{TCCount}=     $session->var_bind_list()->{$dot1dStpTop
+Changes};
       $SysInfo{TCTime}=     $session->var_bind_list()->{$dot1dStpTime
+SinceTopologyChange};
       $SysInfo{RootBridge} = $session->var_bind_list()->{$dot1dStpDes
+ignatedRoot};
       $SysInfo{RootBridge} =~ s/^0x//; # Zap the leading "0x"
       $SysInfo{MaxPorts}=    $session->var_bind_list()->{$dot1dBaseNu
+mPorts};
       if ($session->var_bind_list()->{$ifNumber} != $SysInfo{MaxPorts
+}){
          print "**Problem: Number of Interfaces reported("
                . $session->var_bind_list()->{$ifNumber}
                . ") Disagrees with number of Bridge ports($SysInfo{Ma
+xPorts})\n"
                ;
       }
       $SysInfo{Mac}=         $session->var_bind_list()->{$dot1dBaseBr
+idgeAddress};
       $SysInfo{Mac} =~ s/^0x//; # Zap the leading "0x"
       $SysInfo{Descr}=$session->var_bind_list()->{$sysDescr};
       $SysInfo{Descr}=~
           /([a-zA-Z ]+)\s.*\s([\w\-]*\d+[\w\-]*).*\s[V|R]E[V|R]\w*?\s
+([\w\.\(\)]+)/iso;
       $SysInfo{Manufacturer} = $1;
       $SysInfo{Model} = $2;
       $SysInfo{Version} = $3;
       if (! $SysInfo{Manufacturer}){
          # We did NOT get a Manufacturer - try to Re-parse for SSR, w
+hich is like
          #  6SSRM/6C107 - Enterasys Networks Firmware Version: E9.0.7
+.0 PROM Version: prom-
          $SysInfo{Descr}=~m/(\S+)[\s-]+(\S+).*?\s[V|R]E[V|R][\w:]*?\s
+([\w\.\(\)-]+)/iso;
          $SysInfo{Manufacturer} = $2;
          $SysInfo{Model} = $1;
          $SysInfo{Version} = $3;
       }

       $SysInfo{Host} = $session->hostname;
       # Vertical Horizon's dont report Manufacturer etc ..
       if ($SysInfo{Mac} =~m/^0001f4/ && $SysInfo{MaxPorts}== 26){
            $SysInfo{Manufacturer} = "Enterasys (Guess based on Mac)";
            $SysInfo{Model} = "VH2402";
            $SysInfo{Version} = "No way of knowing";
       }
       #SSR's report themselves differently
       if ($SysInfo{Descr} =~m/^6SSRM.*Version: (\w+)/){
            $SysInfo{Manufacturer} = "Enterasys";
            $SysInfo{Model} = "6SSRM/6C107";
            $SysInfo{Version} = $1;
       }
       while (my ($k, $v) = each %SysInfo){
             print "  SYSTEM $k=$v;\n";
       }
}
#################################################################
sub queryfdb {
   my ($key, $newkey);
   my @PortMacs; # An array of Array ref's
   my @PortDesc; # Description of each port
   my $dot1dBaseBridgeAddress = qq(1.3.6.1.2.1.17.1.1);
   my $dot1dBaseNumPorts      = qq(1.3.6.1.2.1.17.1.2);
   my $dot1dTpFdbAddress      = qq(1.3.6.1.2.1.17.4.3.1.1);
   my $dot1dTpFdbPort         = qq(1.3.6.1.2.1.17.4.3.1.2);
   my $dot1dBasePortIfIndex   = qq(1.3.6.1.2.1.17.1.4.1.2);
   my $ifName                 = qq(1.3.6.1.2.1.31.1.1.1.1);

   my $macref = $session->get_table($dot1dTpFdbAddress);

   $session->error and
      return {error => $session->error};

   #foreach my $oid (oid_lex_sort(keys(%{$macref}))){
   #        print "OID $oid  Mac " . $macref->{$oid} . "\n";
   #}

   my $portref = $session->get_table($dot1dTpFdbPort);
   $session->error and
      return {error => $session->error};

   my $portIfIndex = $session->get_table($dot1dBasePortIfIndex);
   $session->error and
      return {error => $session->error};

   #foreach my $p (oid_lex_sort(keys(%{$portIfIndex}))){
   #        print " PORTIDX $p  IFIDx " . $portIfIndex->{$p} . "\n";
   #}

   my $PortNameRef = $session->get_table($ifName);
   $session->error and
      return {error => $session->error};
   #foreach my $p (oid_lex_sort(keys(%{$PortNameRef}))){
   #        print " PORTNAME for Index $p  Name=" . $PortNameRef->{$p}
+ . ";\n";
   #}

  while (my($portkey,$port) = each %$portref) {
       ($newkey = $portkey) =~ s/$dot1dTpFdbPort\.//;
        # print "Pkey  Port " . $portref->{$portkey}
        #    #. " macKey $dot1dTpFdbAddress\.$newkey; Mac="
        #    . " mac " . $macref->{"$dot1dTpFdbAddress\.$newkey"}
        #    . "\n";
        $port > $FrontPorts[$SysInfo{MaxPorts}] and next; # Dont save 
+uplinks
        my $mac = $macref->{"$dot1dTpFdbAddress\.$newkey"};
        length($mac) < 14 and next ;
        $mac =~ s/0x//;
        my $ifIndex = $portIfIndex->{$dot1dBasePortIfIndex . "\." . $p
+ort};
        ##$ifIndex == $port or print "   IfIndex $ifIndex = Port $port
+ \n";
        push @{$PortMacs[$ifIndex]}, $mac;
        $PortDesc[$ifIndex] =$PortNameRef->{$ifName . "\." . $ifIndex}
+;
  }

   #print "**Port Count = " . scalar(%{$portref})
   #      . " Mac count = " . scalar(%{$macref})
   #      . " Portmac size=" . scalar(@PortMacs)
   #      . "\n";

   #for (my $i = 0; $i < @PortMacs; $i++) {
   #    $PortMacs[$i] or next;
   #    print "--Port $i MACS: @{$PortMacs[$i]} \n";
   #}
   return (\@PortMacs, \@PortDesc);
}
#################################################################
sub showinfo(){
    my ($session,$varname,$oid) = @_;
    my $format="%5d"; # Default format, if numeric
    my $val = $session->var_bind_list()->{$oid};
    if (length($val)> 5  or $val > 9999){
       return $varname . "=" . $val  . "; ";
    }
    return  $varname . "=" .
            sprintf("%6d",
                $val) . "; ";
}
#################################################################
#################################################################
sub ARPtable {
   my %MacbyIP; 
   my $ifName                 = qq(1.3.6.1.2.1.31.1.1.1.1);
   my $ipNetToMediaNetAddress = qq(1.3.6.1.2.1.4.22.1.3); #Idx=Instanc
+e, returns IP
   my $ipNetToMediaPhysAddress= qq(1.3.6.1.2.1.4.22.1.2); #Idx=Instanc
+, Returns Mac
   my $ipNetToMediaIfIndex    = qq(1.3.6.1.2.1.4.22.1.1); #Idx=Instanc
+e, returns IFIdx
   my $ipNetToMediaEntry      = qq(1.3.6.1.2.1.4.22.1); # Entire ARP t
+able (Unused)
   my $ifIndex                = qq(1.3.6.1.2.1.2.2.1.1);
   my $ifDescr                = qq(1.3.6.1.2.1.2.2.1.2);
   my $ifPhysAddress          = qq(1.3.6.1.2.1.2.2.1.6);

   my $IPref = &GetCleanTableRef($ipNetToMediaNetAddress);
   my $Macref= &GetCleanTableRef($ipNetToMediaPhysAddress, "^0x","");
#   my $Portref=&GetCleanTableRef($ipNetToMediaIfIndex);
#   my $IfIdxref=&GetCleanTableRef($ifIndex);
#   my $IfDescref=&GetCleanTableRef($ifDescr);
#   my $IfEthAddrref=&GetCleanTableRef($ifPhysAddress);

   foreach my $idx (sort keys(%{$IPref})){
 #          my $desc = $IfDescref->{$IfIdxref->{$Portref->{$idx}}};
 #          $desc=~s/^IP interface: //;
 #          print " Mac=" . $Macref->{$idx} . " len=" . length($Macref
+->{$idx})
            ##. " Eth=" .  $IfEthAddrref->{$idx}
 #          . " IP=" . $IPref->{$idx}
 # #         . " Port=" . $Portref->{$idx}
 # #         . " Desc=" . $desc
 #           . "\n";  ##. " Idx=$idx\n";
            if (length($Macref->{$idx}) > 11){
               $MacbyIP{$IPref->{$idx}} = $Macref->{$idx};
            }
   }

   return (\%MacbyIP);
}
#################################################################
sub GetCleanTableRef{
   my $oid = shift;
   my ($subst_find, $subst_replacetext)=@_;
   my ($Tab, $NewTab, $newkey);

   $Tab = $session->get_table($oid);
   $session->error and
      die "Error getting $oid : " . $session->error;

   foreach my $idx (keys(%{$Tab})){
           ($newkey = $idx) =~ s/$oid\.//;
          # print "OIDKey=$idx  Info=" . $Tab->{$idx} . " New=$newkey\
+n";
           $NewTab->{$newkey} = $Tab->{$idx};
           $subst_find and $NewTab->{$newkey} =~s/$subst_find/$subst_r
+eplacetext/;
   }
   return $NewTab;
}
#################################################################

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    Earth first! (We'll rob the other planets later)

In reply to Re: using perl for arp collection by NetWallah
in thread using perl for arp collection by Anonymous Monk

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