Static Routing and Basic Router Configurations

STATIC ROUTING AND BASIC ROUTER CONFIGURATIONSStep 1: Addressing and Assigning of IP address Study the given topology. Do the required subnetting scheme, either it is classful or classless. If the instruction says DIVIDE THE BLOCK EQUALLY, use classful otherwise, the addressing scheme is classless. You can do the addressing mentally, however, it is suggested that you create two tables, one for addressing and the other one is for assigning of IP address. As much as possible, the use of calculator, any electronic device and or VLSM calculator is not allowed. Practice VLSM for you will use this technique until Cisco 4. EXAMPLE: INSTRUCTIONS From the given figure, use the 192.168.0.0/16 IP block efficiently. All fast Ethernet interface will use the first usable IP address. All end devices will use the last usable IP address. The two serial ports of R2 will serve as DCE and shall use the first usable IP. Clock rate is 64000

Table 1: Addressing IP BLOCK 192.168.0.0 NetworkLAN B 200 Hosts LAN C 60 Hosts LAN A 50 Hosts WAN 1 2 Hosts WAN 2 2 Hosts

Network Address 192.168.0.0 192.168.1.0 192.168.1.64 192.168.1.128 192.168.1.132

Usable Range 192.168.0.1 192.168.0.254 192.168.1.1-192.168.1.62 192.168.1.65 192.168.1.126 192.168.1.129 192.168.1.130 192.168.1.133 192.168.1.134

Broadcast Address 192.168.0.255 192.168.1.63 192.168.1.127 192.168.1.131 192.168.1.135

Subnet Mask 255.255.255.0 255.255.255.192 255.255.255.192 255.255.255.252 255.255.255.252

Table 2: Assigning of IP address Device Interface S0/0/1 R1 Fa0/0 S0/0/0 R2 S0/0/1 Fa0/0 S0/0/0 R3 Fa0/0 PC0 NIC PC1 NIC PC2 NIC

IP Address 192.168.1.134 192.168.1.1 192.168.1.133 192.168.1.129 192.168.1.65 192.168.1.130 192.168.0.1 192.168.1.62 192.168.1.126 192.168.0.254

Subnet Mask 255.255.255.252 255.255.255.192 255.255.255.252 255.255.255.252 255.255.255.192 255.255.255.252 255.255.255.0 255.255.255.192 255.255.255.192 255.255.255.0

Default Gateway NA NA NA NA NA NA NA 192.168.1.1 192.168.1.65 192.168.0.1

STEP 2: Configuring End Devices For Cisco 1 courses, there are two end devices that are being used PCs and Servers. For this moment, we shall concentrate first on configuring a PC. Configuring servers will be discussed on a separate topic but will also be part of the PT Final Exam. In configuring a PC, there are three basic things that must be considered, the IP address, the subnet mask and the default gateway. BUT keep in mind that if there is a DNS server, the IP address assigned to the DNS server is placed on the DNS server field in configuring a PC. Example Configuring PC0:

NOTE: Make sure that all PCs are configured before you pinging. Also if the LAN has a DHCP server, choose DHCP over static.

STEP 3: Configuring Router Interfaces For this part, the goal is to assign IP address to the router interfaces. There are two ways on how to do this. You can use the CLI tab or if this one is not applicable, you can access the router through a PCs hyper terminal. Make sure that the router is on when accessing the hyper terminal. The syntax to be used is: interface router-interface ip address ip-address subnet-mask clock rate clock-rate (this one is for DCE only) no shutdown EXAMPLE Configuring R1:

Make sure that all router interfaces are configured properly before issuing a ping command. D not forget the clock rate for DCE.

STEP 4: Static Routing After configuring the PCs and the router interfaces, only the directly connected networks are seen on the routing table of each router. For the destination host to be reachable, all the networks present in the topology must be present in the routing table. For Cisco 1, the solution to this one is Static Routing. There are two ways on how to do static routing, first is through the use of next hop and the other one is through the use of the exit interface. Take note that all the networks that are not directly connected to the router must be statically configured. The syntax for static routing is: a. using next hop: ip route destination-network-address subnet-mask next-hop-ip b. using exit-interface ip route destination-network-address subnet-mask exit-interface EXAMPLE: CONFIGURING STATIC ROUTE ON R1:

As seen in the given topology, there are 5 networks that are present 3 LANs (A, B and C) and 2 WANs (1 and 2). However, among the 5 networks, only 2 are considered as directly connected to R1 these are LAN C and WAN 2. With that, the three remaining networks must be configured statically to R1. These networks are WAN 1, LAN A and LAN C. Using NEXT-HOP, R1 must be configured this way: adding LAN A Network address of LAN A: 192.168.1.64 Subnet Mask of LAN A: 255.255.255.192 Next hop IP: 192.168.1.133 (this is the ip address of R2s S0/0/0) ip route 192.168.1.64 255.255.255.192 192.168.1.133

doing the same thing for LAN C and WAN 1:

USING EXIT-INTERFACE: adding LAN A Network address of LAN A: 192.168.1.64 Subnet Mask of LAN A: 255.255.255.192 Next hop IP: S0/0/1 (exit interface of R1 going to the destination network) ip route 192.168.1.64 255.255.255.192 s0/0/1 doing the same thing:

In using next-hop or exit interface the results are just the same. The difference lies on the result of their routing table. If next-hop ip is used, recursive look-up will occur. This topic is covered in CCNA 2, for the mean time, just be mindful in using next-hop IP and exit interface. For better understanding, we will also configure R2 using next hop and exit interface. For R2, there are 3 directly connected networks; therefore, only two networks must be configured statically. These are LAN C and LAN B.

Using next-hop:

Take note of the differences in the next-hop ip.

USING EXIT INTERFACE:

Take note of the exit interfaced that is used.

NOTE: As mentioned, there are two ways on how to configure static routing, that is through the use of next hop ip and the other one is through the use of exit interface. In doing the Packet Tracer Exercises, you dont need to do both of them. It depends upon the instruction if you are going to use exit interface of next hop.

STEP 5: configuring default route Default route is used so that the routing table entries will be lessen. For example, in configuring R1, there are three remote networks (not directly connected). However, using default route, this one can be represented by 1 route only. Syntax: ip route 0.0.0.0 0.0.0.0 next-hop-ip or ip route 0.0.0.0 0.0.0.0 exit-interface

In configuring default route to R1 using next-hop-ip this one shall be used: ip route 0.0.0.0 0.0.0.0 192.168.1.133 using exit-interface: ip route 0.0.0.0 0.0.0.0 s0/0/1 NOTE: Only one default route is used to represent all the remotely connected networks of R1 since nexthop ip and exit interface used in going to these networks are the same. However for R2, since the nexthop ip nor the exit interface used in reaching the remotely connected networks are NOT the same, TWO default routes are needed in configuring R2 with default route. For R2: Using next hop: ip route 0.0.0.0 0.0.0.0 192.168.1.134 ip route 0.0.0.0 0.0.0.0 192.168.1.130 using exit-interface ip route 0.0.0.0 0.0.0.0 s0/0/0 ip route 0.0.0.0 0.0.0.0 s0/0/1

HOUSEKEEPING COMMANDSROUTER MODE Global Configuration SYNTAX line con 0 password password login line con 0 logging synchronous login PURPOSE Setting a Console Password

Global configuration

Global configuration

Global configuration Global configuration Global Configuration Global Configuration Global Configuration Any Mode

line vty 0 4 password password login enable password password enable secret password service password-encryption hostname hostname banner motd *message* Ctrl + z end exit enable Configure terminal copy running-config startupconfig ping destination-ip show running-config show ip route show ip interfaces

For synchronized message output or to disable the router from going back to user executive mode when not in used. Setting telnet password

Setting enable password (not encrypted) Setting enable password (automatically encrypted) This will encrypt the console and vty passwords. Change the hostname Issue a message of the day banner Exiting from one configuration to another Entering the privileged executive mode Entering the global configuration mode Copy the running configuration stored in RAM to startup configuration stored in NVRAM Issue a ping command using a router show the routers running configuration Show the routers routing table Displays IPv4 statistics for all interfaces on a router. To view the statistics for a specific interface, enter the show ip interfaces command followed by the specific interface slot/port number. Another important format of this command is show

User executive privileged executive privileged executive

privileged executive privileged executive privileged executive privileged executive

privileged executive Global Configuration Global Configuration

Show startup-config do show running-config do show ip route

ip interface brief. This gets a quick summary of the interfaces and their operational states Displays the saved configuration located in NVRAM. show the routers running configuration Show the routers routing table

Hot keys and Shorcuts: Tab - Completes the remainder of the command or keyword Ctrl-R - Redisplays a line Ctrl-Z - Exits configuration mode and returns to the EXEC Down Arrow - Allows user to scroll forward through former commands (Ctrl-N) Up Arrow - Allows user to scroll backward through former commands (Ctrl-P) Ctrl-Shift-6 - Allows the user to interrupt an IOS process such as ping or traceroute Ctrl-C - Aborts the current command and exits the configuration mode NOTE: Switches are also configured in the same way as with router. However, instead of fast Ethernet interfaces, vlan1 is used for example: interface vlan1 ip address 192.168.0.1 255.255.255.0 no shut then the rest of the housekeeping commands are the same.