#!/usr/bin/perl
use warnings;
use strict;

my %devinfo;

while (<DATA>) {
  next unless my ($date,$time, $device, $err) = /(\w+ \d+) ([\d:]+)\s(\S+) \[[^\]]+\]([^\(]+)\s?\(\d+/;
  $devinfo{$device}{$err}{COUNT}++;
  $devinfo{$device}{$err}{FIRST_TIME} ||= [$date, $time];
}

for my $dev (sort keys %devinfo) {

    print "DEVICE\t--> $dev ==============\n";
    for my $err (keys %{ $devinfo{$dev} }) {
      my $errinfo = $devinfo{$dev}{$err};
      print "DATE\t--> $errinfo->{FIRST_TIME}[0]\n";
      print "TIME\t--> $errinfo->{FIRST_TIME}[1]\n";
      print "ERROR\t--> $err\n";
      print "\nThe above error occurred $errinfo->{COUNT} times\n\n";
   }
}
__DATA__
<put data here>

##</code><code>##

DEVICE	--> esw001tff2 ==============
DATE	--> Oct 17
TIME	--> 10:35:43
ERROR	--> Server reset. Occurred 1 time. 

The above error occurred 2 times

DATE	--> Oct 17
TIME	--> 10:35:39
ERROR	--> IP Spoofing from 255.255.255.255 to 255.255.255.255! Occurred 1 time. 

The above error occurred 7 times

DATE	--> Oct 17
TIME	--> 10:35:47
ERROR	--> Root login failure! Occurred 1 time. 

The above error occurred 3 times