# Switching between different VLANs

Introduction

The goal is to do switching between VLAN 10 and VLAN 20.
VLAN 10 is on Switch1, VLAN20 is on Switch2, and VLAN30 is on both switches.

Native VLAN

Switch1(config)# vtp mode transparent
Switch1(config)# interface gi0/1
Switch1(config-if)# switchport
Switch1(config-if)# switchport mode trunk
Switch1(config-if)# switchport trunk encapsulation dot1q
Switch1(config-if)# switchport trunk allowed vlan 10,30
Switch1(config-if)# switchport trunk native vlan 10
Switch1(config-if)# no cdp enable
Switch1(config-if)# spanning-tree bpdufilter enable

Switch2(config)# vtp mode transparent
Switch2(config)# interface gi0/1
Switch2(config-if)# switchport
Switch2(config-if)# switchport mode trunk
Switch2(config-if)# switchport trunk encapsulation dot1q
Switch2(config-if)# switchport trunk allowed vlan 20,30
Switch2(config-if)# switchport trunk native vlan 20
Switch1(config-if)# no cdp enable
Switch2(config-if)# spanning-tree bpdufilter enable

VLAN translation (mapping)

Switch1(config)# vtp mode transparent
Switch1(config)# interface gi0/1
Switch1(config-if)# switchport
Switch1(config-if)# switchport mode trunk
Switch1(config-if)# switchport trunk encapsulation dot1q
Switch1(config-if)# switchport trunk allowed vlan 10,30

Switch2(config)# vtp mode transparent
Switch2(config)# interface gi0/1
Switch2(config-if)# switchport
Switch2(config-if)# switchport mode trunk
Switch2(config-if)# switchport trunk encapsulation dot1q
Switch2(config-if)# switchport trunk allowed vlan 20,30
Switch2(config-if)# switchport vlan mapping enable
Switch2(config-if)# switchport vlan mapping 10 20

# EIGRP summary

Basic

Router(config)#router eigrp 65000
Router(config-router)#network 192.168.0.0 0.0.255.255
Router(config)#ip default-network 192.168.1.0
Router(config-router)#passive-interface default
Router(config-router)#no passive-interface Ethernet0

Summarization

Router(config-router)# ! Transmit subprefix information
Router(config-router)#no auto-summary
Router(config-if)# ! Manual summarization
Router(config-if)#ip summary-address eigrp 65000 172.16.0.0 255.255.0.0

Load balancing

Router(config-router)# ! Unequal cost path load balancing
Router(config-router)# ! Metric < 2*best_metric
Router(config-router)#variance 2
Router(config-router)# ! Proportionately to the ratios of the metrics
Router(config-router)#traffic-share balanced

Bandwidth utilization

Router(config-if)#bandwidth 100000
Router(config-if)# ! 25Mbps for EIGRP traffic (default 50%)
Router(config-if)#ip bandwidth-percent eigrp 65000 25

Stub routing

HubRouter(config-router)#eigrp stub
HubRouter(config-router)#neighbor 192.168.1.1 Ethernet 0
SpokeRouter(config-router)#no ip split-horizon 65000
SpokeRouter(config-router)#neighbor 192.168.1.2 Ethernet 0

Timers

Router(config-if)#ip hello-interval eigrp 65000 2
Router(config-if)#ip hold-time eigrp 65000 8 ! ~ 3*hello-interval

Authentication

Router(config-if)#ip authentication mode eigrp 65000 md5
Router(config-if)#ip authentication key-chain eigrp 65000 eigrp_key

Verification

Router#show ip eigrp neighbors
Router#show ip eigrp topology
Router#show ip eigrp traffic
Router#debug ip eigrp packet
Router#debug ip eigrp neighbors
Router#debug ip eigrp summary
Router#debug ip eigrp

# Cisco IOS scheduling with Kron

Introduction

Cisco documentation.

Kron does not allow the execution of commands from global configuration mode, only from privileged EXEC mode.

Oneshot

Router(config)# kron policy-list kpl-reload
Router(config-kron-policy)# cli reload
Router(config-kron-policy)# exit
Router(config)# kron occurrence ko-reload in 1 oneshot
Router(config-kron-occurrence)# policy-list kpl-reload
Router(config-kron-occurrence)# exit
Router# show kron schedule

At time and recurring

Router(config)# kron policy-list kpl-clear_arp
Router(config-kron-policy)# cli send log Clear ARP cache
Router(config-kron-policy)# cli clear arp-cache interface fa0/1
Router(config-kron-policy)# exit
Router(config)# kron occurrence ko-clear_arp-07:00h at 07:00 recurring
Router(config-kron-occurrence)# policy-list kpl-clear_arp
Router(config-kron-occurrence)# exit
Router(config)# kron occurrence ko-clear_arp-15:00h at 15:00 recurring
Router(config-kron-occurrence)# policy-list kpl-clear_arp
Router(config-kron-occurrence)# exit
Router# show kron schedule

# Windows command line

Help

C:\>help dir
C:\>dir /?

Echo

C:\>echo on
C:\>echo off
C:\>echo Test
C:\>echo.
C:\>@help rem

Regular expressions

C:\>dir *.txt
C:\>dir ???.txt

Redirections

C:\>echo x > file01.txt
C:\>pause < file01.txt
C:\>type file02.txt 2> error.txt
C:\>type file03.txt > output_error.txt 2>&1

Filters

C:\>echo x | pause
C:\>dir | more
C:\>dir | sort | more
C:\>findstr "good night" file04.txt

Environment variables

C:\>set | more
C:\>set var1=1
C:\>ser var2=2
C:\>set var
C:\>set var1=
C:\>set var2=
C:\>set path=%path%;dir01
C:\>echo %computername%
C:\>echo %date%
C:\>echo %time%
C:\>echo %errorlevel%
C:\>echo %number_of_processors%
C:\>echo %os%
C:\>echo %path%
C:\>echo %pathext%
C:\>echo %processor_architecture%
C:\>echo %processor_identifier%
C:\>echo %processor_level%
C:\>echo %processor_revision%
C:\>echo %random%

Copy files

C:\>rem Copy files and directories recursively
C:\>xcopy /?

Compare files

C:\>rem Compare
C:\>comp file1 file2
C:\>rem Compare
C:\>fc file1 file2

Adjusting de cmd

C:\>rem Size
C:\>mode 120x120
C:\>rem Color [0xbackground, 0xforeground]
C:\>color 0a
C:\>rem Window title
C:\>title Network info

Directory listing

C:\>tree /a /f C:\

Scripts

C:\>type script.cmd
@echo off
rem script.cmd
cls
echo.
echo Script name: %0
echo First parameter: %1
echo Second parameter: %2
for %%i in (*.txt) do type %%i
C:\>script p1 p2

Escape

C:\>echo a is ^> than b

Flux control

C:\>call script.cmd %1 %2
C:\>cmd /k dir
C:\>start dir
C:\>for %i in (*.txt) do type %i
C:\>for /D /r %i in (*) do @echo dir: %i
C:\>for /R %i in (*.bak) do del %i
C:\>for /L %i in (1,1,10) do @echo %i
C:\>echo "a 1" >> file05.txt
C:\>echo "b 2" >> file05.txt
C:\>echo "c 3" >> file05.txt
C:\>for /F "tokens=1,2" %i in (file05.txt) do @echo t2=%j t1=%i
C:\>for /F "delims=: tokens=1-2 usebackq" %i in (`time /t`) do @echo %i:%j
C:\>type file06.txt
@echo off
goto message2
echo message1
:message2
echo message2
C:\>if not exist file07.txt echo "No file"
C:\>exit /b 0

# TCL scripting for IOS

Introduction

Documentation

Loops

Router#tclsh
Router(tcl)#for {set i 1} {$i<10} {incr i} {
+> for {set j 1} {$j<3} {incr j} {
+>  ping 192.168.$i.$j repeat 1 timeout 1
+> }
+>}

Router(tcl)#foreach address {
+>192.168.0.1
+>192.168.0.10
+>192.168.0.100
+>} {ping $address}

Procedures

Router(tcl)#proc p {text} {
+> puts $text
+>}

Router(tcl)#p "Hello world!"

# Network performance tools

iperf

server# apt-get install iperf
server# iperf -s -p 5001 -f m

client# apt-get install iperf
client# iperf -c 192.168.1.100 -p 5001 -f m -L 5002 -d

nttcp

server# apt-get install nttcp
server# nttcp -i -p 5001

client# apt-get install nttcp
client# nttcp -T -t -p 5001 -v 192.168.1.100 # transmit
client# nttcp -T -r -p 5001 -v 192.168.1.100 # receive

ttcp

server_router#ttcp receive
client_router#ttcp transmit 192.168.1.200

# Scapy

Introduction

Documentation

Execution

# apt-get install python-scapy
# scapy
>>> ### Basic
>>>
>>> ls() # list available packets
>>> ls(IP) # list attributes of an IP packet
>>> lsc() # list of commands
>>> conf # list the configuration
>>> conf.iface = "eth0" # set values in configuration
>>>
>>> ### Sniffing
>>>
>>> # In one terminal
>>> arping("192.168.1.0/24")
>>> # In another terminal
>>> sniff(filter = "arp")
>>> _.display()
>>>
>>> ### Read pcaps
>>>
>>> rdpcap("icmp.pcap")
>>> _.display()
>>> icmp=_
>>> icmp.display()
>>> icmp[0][IP].src

# Sockets in python

Execution

server# cat pyserver 
#!/usr/bin/python

import socket
import sys

HOST = 'localhost'
PORT = 1024

server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
server.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

server_socket = (HOST, PORT)
server.bind(server_socket)
print 'Starting up on %s port %s' % server_socket

server.listen(5)

while True:
 try:
  connection, client_socket = server.accept()
  print 'Connection from', client_socket

  data = connection.recv(4096)

  if data:
   print 'Received', data
   data = data.strip()
   connection.send('%s\n%s ack\n%s' % ('-'*15, data, '-'*15))

  connection.shutdown(socket.SHUT_RD | socket.SHUT_WR)

 except KeyboardInterrupt, e: # CTRL+C
  print ''
  break

connection.close()
print 'Connection closed'

server.close()

server# ./pyserver

client# cat client 
#!/usr/bin/python

import socket
import sys

HOST = 'localhost'
PORT = 1024

client = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

server_socket = (HOST, PORT)
client.connect(server_socket)

client.send(sys.argv[1])
data = client.recv(1024)

client.close()

print 'Received:'
print data

client# ./pyclient

# Hydra: network password cracker

Introduction

Hydra
Default password list

Execution

# apt-get install libssh-dev
# wget http://freeworld.thc.org/releases/hydra-6.3-src.tar.gz
# tar xvzf hydra-6.3-src.tar.gz
# cd hydra-6.3-src
# ./configure
# make
# ./hydra -h
# ./hydra -l foo -p bar -f 127.0.0.1 http-get -m /
# ./hydra -l root -P john_password.lst 127.0.0.1 ssh -s 2222
# ./hydra -l root 8:8:a -f 127.0.0.1 mysql

# Cracking wep

Introduction

Wi-Fi Challenge 3a

Execution

# wget http://code.securitytube.net/Challenge-3a
# file Challenge-3a
# scapy
>>> ch3a = rdpcap("Challenge-3a")
>>> ch3a.display()
>>> ch3a[0]
>>> ch3a[1]
>>> exit()
# cat wepcrack
#!/usr/bin/python

import sys
from scapy.all import *
import Crypto.Cipher.ARC4 as ARC4

pcap = rdpcap("Challenge-3a")
wordlist = open('passwd.lst', 'r')

info = pcap[0].info
iv = pcap[1].iv
wepdata = pcap[1].wepdata

for line in wordlist:
 line = line.strip()
 ivkey = iv + line
 arc4 = ARC4.new(ivkey)
 clear = arc4.decrypt(wepdata)
 
 print 'Trying key', line

 if info in clear:
  print '\nFound Key:', line
  wordlist.close()
  sys.exit()

# ./wepcrack