Commonly Using Port Numbers

Port	TCP	UDP	Description
20	x		FTP-Data
21	x		FTP (login access)
22	x	x	SSH
23	x		Telent
25	x		SMTP (Mail, MTA)
49	x		TACACS+
53	x	x	DNS
69		x	TFTP
80	x	x	HTTP (Web)
110	x	x	POP3 (email); generally uses TCP)
119	x		NNTP (Usenet News)
123		x	NTP
139	x	x	NetBIOS (Microsoft)
143	x	x	IMAP
161	x	x	SNMP (Network Monitor)
179	x		BGP
443	x	x	HTTPS
465	x		SMTPS (Secure Mail over SSL)
993	x	x	IMAP (Secure IMAP over SSL)
995	x	x	POP3S (Secure POP3 over SSL)
1645,1812		x	RADIUS Authentication
1646,1813		x	RADIUS Accounting

Installing GNS3 on CentOS 6.x/RHEL 6.x/Fedora 15

1. Login as root then do the following steps:
   yum install python python-devel xorg-x11-proto-devel libXext-devel gcc-c++ libXrender*


2. Download and install Qt
   #wget http://get.qt.nokia.com/qt/source/qt-everywhere-opensource-src-4.7.4.tar.gz
   #tar -xzf qt-everywhere-opensource-src-4.7.4.tar.gz
   #cd qt-everywhere-opensource-src-4.7.4
   #./configure -nomake examples -nomake demos -qt-gif -no-exceptions -debug -qt3support
   #gmake
   #gmake install
   #PATH=/usr/local/Trolltech/Qt-4.7.4/bin:$PATH
   #export PATH


3. Download and install sip
   #wget http://www.riverbankcomputing.co.uk/static/Downloads/sip4/sip-4.13.tar.gz
   #tar -xvf sip-4.13.tar.gz
   #cd sip-4.13.tar
   #python configure.py
   #make
   #make install


4. Download and install PyQt
   #wget http://ftp.pardus.org.tr/pub/source/2009/PyQt-x11-gpl-4.8.4.tar.gz
   #tar xvf PyQt-x11-gpl-4.8.4.tar.gz
   #cd PyQt-x11-gpl-4.8.4
   #python configure.py -q /usr/local/Trolltech/Qt-4.7.4/bin/qmake
   #make
   #make install


5. Download GNS3
   #wget http://downloads.sourceforge.net/project/gns-3/GNS3/0.7.4/GNS3-0.7.4-src.tar.gz
   #tar -xvf GNS3*.tar.gz && rm GNS3*.tar.gz
   #cd GNS3-0.7.4-src
   #mkdir Dynamips IOS Project Cache Temp


6. Download Dynamips depending up on OS (64-bit/32-bit)
   #cd dynamips
   #wget http://downloads.sourceforge.net/gns-3/dynamips-0.2.8-RC2-amd64.bin?download (for 64-bit OS)
   #wget http://downloads.sourceforge.net/gns-3/dynamips-0.2.8-RC3-community-x86.bin?download (for 32-bit OS)
   #chmod +x dynamips-0.2.8-RC2-amd64.bin (if we use 32-bit version, use the name of that file)


7. Creating Quick launch with gns3 icon
   #wget http://www.noahbeach.com/wp-content/uploads/2011/08/gns3.png
   Now right click on the panel and select add to panel > custom launcher > select the gns3 location and press on the icon button to locate the icon just downloaded. ok
   Now if we press that icon in the panel, gns3 will run...!!!

Configuring router for SDM

SDM configuration steps:

1. Create user accounts
2. Enable http and/or https server
3. Configure http to use local user database

R1(config)#username binoy privilege 15 secret cisco
R1(config)#ip http server
R1(config)#ip http secure-server (allows encrypted access)
R1(config)#ip http authentication local

Now download SDM from www.cisco.com/go/sdm and install it in the computer (requires java runtime environment) and launch the SDM by giving IP address in SDM launcher

Cisco router password recovery process

1. Connect to console port
2. Use the power switch to power cycle the router.
3. Issue the break sequence within 60 seconds of power up to put the router into ROMmon.
4. Type “confreg 0x2142” at the rommon 1> prompt.  (This changes the default configuration register and causes the router to bypass the startup configuration where the forgotten enable password is stored.The configuration register is usually set to 0x2102 or 0x102)
5. Type no after each setup question, or press Ctrl-C to skip the initial setup procedure.
6. Router> enable
7. Router#copy start run
8. Now, change the passwords and give no shutdown commands to interfaces
9. R1(config)# config-register 0x2102 (To make the startup configuration effective while next booting)

Creating Site-to-Site VPNs with Pre-Shared Keys

Documentation:
1. Document your IKE Phase 1 negotiation criteria (example below)

• Encryption algorithm: AES-128
• Hashing: SHA-1
• Authentication: pre-shared
• Key exchange: Diffie-Hellman Group 2

2. Document your IPSec (IKE Phase 2) negotiation criteria (example below)

• Encryption algorithm: esp-aes 128
• Authentication: esp-sha-hmac

Configuring IKE Phase 1:
1. Enable ISAKMP: Router(config)#crypto isakmp enable
2. Create ISAKMP Policy: Router(config)#crypto isakmp policy <1-10000>

• Router(config)#crypto isakmp policy 100
• Router(config-isakmp)#encryption aes 128
• Router(config-isakmp)#authentication pre-share
• Router(config-isakmp)#group 2
• Router(config-isakmp)#hash sha

3. Configure ISAKMP Identity: Router(config)#crypto isakmp identity <address/hostname>
4. Configure pre-shared keys: Router(config)#crypto isakmp key <key> address <remote_ip>
Configuring IKE Phase 2:
1. Create transform sets: Router(config)#crypto ipsec transform-set <name> <methods>

• Router(config)#crypto ipsec transform-set JEREMY esp-aes 128 esp-sha-hmac

2. (optional) Configure IPSec lifetime: : Router(config)#crypto ipsec <seconds/kilobytes> <value>
3. Create mirrored ACLs defining traffic to be encrypted and the traffic expected to be received encrypted
4. Set up IPSec crypto-map: Router(config)#crypto isakmp map <name> <seq> ipsec-isakmp

• Router(config)#crypto map MAP 100 ipsec-isakmp
• Router(config-crypto-map)#match address <acl>
• Router(config-crypto-map)#set peer <remote_ip>
• Router(config-crypto-map)#set pfs <group1/2/5>
• Router(config-crypto-map)#set transform-set <set>

Verify:

• show crypto isakmp policy
• show crypto ipsec transform-set
• show crypto ipsec sa
• show crypto map
• debug crypto isakmp
• debug crypto ipsec