CCNA Exploration 4.0: Routing Protocols and Concepts – Chapter 2 Exam Answers

1 A static route that points to the next hop IP will have what administrative distance and metric in the routing table?

administrative distance of 0 and metric of 0
administrative distance of 0 and metric of 1
* administrative distance of 1 and metric of 0
administrative distance of 1 and metric of 1

2 What address can be used to summarize networks 172.16.1.0/24, 172.16.2.0/24, 172.16.3.0/24, and 172.16.4.0/24?

* 172.16.0.0/21
172.16.1.0/22
172.16.0.0 255.255.255.248
172.16.0.0 255.255.252.0

3

The routers in the diagram use the subnet assignments shown. What is the most efficient route summary that can be configured on Router3 to advertise the internal networks to the cloud?

192.1.1.0/26 and 192.1.1.64/27
192.1.1.128/25
192.1.1.0/23 and 192.1.1.64/23
192.1.1.0/24
* 192.1.1.0/25
192.1.1.0/24 and 192.1.1.64/24

4

Refer to the exhibit. What is the significance of the /8 in the route to the 10.0.0.0 network?

It indicates that there are 8 hops between this router and the 10.0.0.0 network.
It represents the time, in milliseconds, it takes for a ping to reply when sent to the 10.0.0.0 network.
It indicates that there are 8 subnets in the destination network to which the router can forward packets.
* It indicates the number of consecutive bits, from the left, in the destination IP address of a packet that must match 10.0.0.0 to use that route.

5

Refer to the exhibit. How will packets destined to the 172.16.0.0 network be forwarded?

* Router1 will perform recursive lookup and packet will exit S0/0.
Router1 will perform recursive lookup and packet will exit S0/1.
There is no matching interface associated with network 172.16.0.0 so packets will be dropped.
There is no matching interface associated with network 172.16.0.0 so packets will take gateway of last resort and exit out S0/2.

6 A network administrator enters the following command into Router1: ip route 192.168.0.0 255.255.255.0 S0/1/0. Router1 then receives a packet that is destined for 192.168.0.22/24. After finding the recently configured static route in the routing table, what does Router1 do next to process the packet?

drops the packet because the destination host is not listed in the routing table
looks up the MAC address of the S0/1/0 interface to determine the destination MAC address of the new frame
performs a recursive lookup for the IP address of the S0/1/0 interface before forwarding the packet
* encapsulates the packet into a frame for the WAN link and forwards the packet out the S0/1/0 interface

7
Refer to the exhibit. Given the output in the exhibit, how would a clock rate be determined for this link?

The rate would be negotiated by both routers.
A rate would not be selected due to the DCE/DTE connection mismatch.
The rate configured on the DTE determines the clock rate.
* The rate configured on the DCE determines the clock rate.

8
Refer to the exhibit. Which set of commands will configure static routes that will allow the WinterPark and the Altamonte routers to deliver packets from each LAN and direct all other traffic to the Internet?

* WinterPark(config)# ip route 0.0.0.0 0.0.0.0 192.168.146.1
Altamonte(config)# ip route 10.0.234.0 255.255.255.0 192.168.146.2
Altamonte(config)# ip route 0.0.0.0 0.0.0.0 s0/1
WinterPark(config)# ip route 0.0.0.0 0.0.0.0 192.168.146.1
Altamonte(config)# ip route 10.0.234.0 255.255.255.0 192.168.146.2
Altamonte(config)# ip route 198.18.222.0 255.255.255.255 s0/1
WinterPark(config)# ip route 172.191.67.0 255.255.255.0 192.168.146.1
WinterPark(config)# ip route 0.0.0.0 0.0.0.0 192.168.146.1
Altamonte(config)# ip route 10.0.234.0 255.255.255.0 192.168.146.2
WinterPark(config)# ip route 172.191.67.0 255.255.255.0 192.168.146.1
Altamonte(config)# ip route 10.0.234.0 255.255.255.0 192.168.146.2
Altamonte(config)# ip route 0.0.0.0 0.0.0.0 s0/0

9 Hosts on two separate subnets cannot communicate. The network administrator suspects a missing route in one of the routing tables. Which three commands can be used to help troubleshoot Layer 3 connectivity issues? (Choose three.)

* ping
show arp
* traceroute
* show ip route
show interface
show cdp neighbor detail

10
Refer to the exhibit. A company network engineer is assigned to establish connectivity between the two Ethernet networks so that hosts on the 10.1.1.0/24 subnet can contact hosts on the 10.1.2.0/24 subnet. The engineer has been told to use only static routing for these company routers. Which set of commands will establish connectivity between the two Ethernet networks?

R1(config)# ip route 10.1.2.0 255.255.255.0 192.168.0.1
R2(config)# ip route 10.1.1.0 255.255.255.0 192.168.0.2
R1(config)# ip route 10.1.2.0 255.255.255.0 192.168.0.2
R2(config)# ip route 10.1.1.0 255.255.255.0 192.168.0.1
* R1(config)# ip route 10.1.1.0 255.255.255.0 192.168.0.2
R2(config)# ip route 10.1.2.0 255.255.255.0 192.168.0.1
R1(config)# ip route 10.1.1.0 255.255.255.0 192.168.0.1
R2(config)# ip route 10.1.2.0 255.255.255.0 192.168.0.2
R1(config)# ip route 0.0.0.0 0.0.0.0 10.1.2.1
R2(config)# ip route 0.0.0.0 0.0.0.0 10.1.1.1

11 Which of the following are displayed by the Router# show cdp neighbors command? (Choose three.)

load
* platform
reliability
* holdtime
* local interface

12
Refer to the exhibit. What two commands are required to provide connectivity between the 192.168.1.0 and 10.0.0.0 networks without requiring recursive lookup? (Choose two.)

* A(config)# ip route 10.0.0.0 255.0.0.0 s 0/1/0
A(config)# ip route 10.0.0.0 255.0.0.0 172.16.40.2
A (config)# ip route 10.0.0.0 255.0.0.0 s 0/0/0
* B(config)# ip route 192.168.1.0 255.255.255.0 s 0/0/0
B (config)# ip route 192.168.1.0 255.255.255.0 172.16.40.1
B(config)# ip route 192.168.1.0 255.255.255.0 s 0/1/0

13
Refer to the exhibit. What two commands will change the next-hop address for the 10.0.0.0/8 network from 172.16.40.2 to 192.168.1.2? (Choose two.)

A(config)# no network 10.0.0.0 255.0.0.0 172.16.40.2
A(config)# no ip address 10.0.0.1 255.0.0.0 172.16.40.2
* A(config)# no ip route 10.0.0.0 255.0.0.0 172.16.40.2
A(config)# ip route 10.0.0.0 255.0.0.0 s0/0/0
* A(config)# ip route 10.0.0.0 255.0.0.0 192.168.1.2

14 What happens to a static route entry in a routing table when the outgoing interface is not available?

* The route is removed from the table.
The router polls neighbors for a replacement route.
The route remains in the table because it was defined as static.
The router redirects the static route to compensate for the loss of the next hop device.

15 A router has one static route to each destination network. Which two scenarios would require an administrator to alter the static routes that are configured on that router? (Choose two.)

* The destination network no longer exists.
The destination network is moved to a different interface on the same router.
The path between the source and destination is upgraded with a higher bandwidth link.
* A topology change occurs where the existing next-hop address or exit interface is not accessible.
The remote destination network interface has to be down for 15 minutes of maintenance.

16 Why is it advisable to enter a next-hop IP address when creating a static route whose exit interface is an Ethernet network?

Adding the next-hop address eliminates the need for the router to do any lookups in the routing table before forwarding a packet.
* In a multi-access network, the router cannot determine the next-hop MAC address for the Ethernet frame without a next-hop address.
Using a next-hop address in a static route provides a route with a lower metric.
In multi-access networks, using a next-hop address in a static route makes that route a candidate default route.

17 The output of the Router# show interfaces serial 0/1 command displays the following:

Serial0/1 is up, line protocol is down.

What is the most likely cause for the line protocol being down?

Serial0/1 is shutdown.
There is no cable connecting the routers.
The remote router is using serial 0/0.
* No clock rate has been set.

18
Refer to the exhibit. Which static route should be configured on Router1 so that host A will be able to reach host B on the 172.16.0.0 network?

ip route 192.168.0.0 172.16.0.0 255.255.0.0
ip route 172.16.0.0 255.255.0.0 192.168.0.1
ip route 172.16.0.0 255.255.0.0 S0/0/1
* ip route 172.16.0.0 255.255.0.0 S0/0/0

19 What two devices are responsible for converting the data from the WAN service provider into a form acceptable by the router? (Choose two).

the serial port of the router
* a modem
a switch
the ethernet port of the router
* a CSU/DSU device
a DTE device

20
Which of the following is true regarding CDP and the graphic shown?

CDP running on Router D will gather information about routers A, B, C, and E.
* By default, Router A will receive CDP advertisements from routers B and C.
If routers D and E are running different routing protocols, they will not exchange CDP information.
Router E can use CDP to identify the IOS running on Router B.

21 Which two statements describe functions or characteristics of CDP? (Choose two.)

* It starts up automatically and allows the device to detect directly connected neighbor devices that use CDP.
It operates at the network layer and allows two systems to learn about each other.
It creates a topology map of the entire network.
* It allows systems to learn about each other even if different network layer protocols are configured.
It forwards advertisements about routes for faster convergence.

22 Which piece of information is available from examining the output of the command show ip interface brief?

Interface speed and duplex
Interface MTU
Errors
Interface MAC address
* Interface IP address

CCNA Exploration 4.0: Routing Protocols and Concepts – Chapter 3 Exam Answers [100%]

1. Which two statements correctly describe the concepts of administrative distance and metric? (Choose two.)

* Administrative distance refers to the trustworthiness of a particular route.
A router first installs routes with higher administrative distances.
The value of the administrative distance can not be altered by the network administrator.
* Routes with the smallest metric to a destination indicate the best path.
The metric is always determined based on hop count.
The metric varies depending which Layer 3 protocol is being routed, such as IP or IPX.

2.

Refer to the exhibit. Which statement correctly describes how R1 will determine the best path to R2?

R1 will install a RIP route using network A in its routing table because the administrative distance of RIP is higher than EIGRP.
R1 will install a RIP route using network A in its routing table because the path cost from RIP is lower than EIGRP.
* R1 will install an EIGRP route using network B in its routing table because the administrative distance of EIGRP is lower than RIP.
R1 will install an EIGRP route using network B in its routing table because the path cost from EIGRP is lower than RIP.
R1 will install an EIGRP route and a RIP route in its routing table and load balance between them.

3. Which two statements are true regarding classless routing protocols? (Choose two.)

* sends subnet mask information in routing updates
sends complete routing table update to all neighbors
is supported by RIP version 1
* allows for use of both 192.168.1.0/30 and 192.168.1.16/28 subnets in the same topology
reduces the amount of address space available in an organization

4. Which command would the network administrator issue to determine if load balancing is in effect on a router?

show ip protocols
* show ip route
show ip interface brief
show ip interface

5. Which statement is true regarding routing protocols?

RIP uses hop count and bandwidth as the metric for path selection and sendsupdates periodically.
OSPF is a Cisco proprietary protocol that sends updates triggered by topology changes.
* EIGRP uses DUAL to calculate the shortest path and can be configured to do unequal cost load balancing.
BGP is a path vector interior routing protocol.

6. Which two conditions would create a setting where the use of a distance-vector routing protocol would be efficient? (Choose two.)

the network requires a special hierarchical design
fast convergence of the network is crucial
* the network is using a hub and spoke topology
* the network is using a flat design
there are more than 15 hops between the most distant routers

7. What is the purpose of a routing protocol?

It is used to build and maintain ARP tables.
It provides a method for segmenting and reassembling data packets.
It allows an administrator to devise an addressing scheme for the network.
* It allows a router to share information about known networks with other routers.
It provides a procedure for encoding and decoding data into bits for packet forwarding.

8. Which of the following best describes the operation of distance vector routing protocols?

They use hop count as their only metric.
They only send out updates when a new network is added.
* They send their routing tables to directly connected neighbors.
They flood the entire network with routing updates.

9. Which of the following is associated with link-state routing protocols?

low processor overhead
poison reverse
routing loops
split horizon
* shortest-path first calculations

10. Why is fast convergence desirable in networks that use dynamic routing protocols?

Routers will not allow packets to be forwarded until the network has converged.
Hosts are unable to access their gateway until the network has converged.
* Routers may make incorrect forwarding decisions until the network has converged.
Routers will not allow configuration changes to be made until the network has converged.

11. Which of the following conditions must be met in order for a network to have converged?

The routers in the network are operating with dynamic routing protocols.
The routers in the network are operating with compatible versions of IOS.
The routers in the network are operating with the same routing tables.
* The routers in the network are operating with consistent routing knowledge.

12. Which two statements are true regarding metrics? (Choose two.)

RIP uses bandwidth as a metric.
OSPF uses delay as a metric.
* EIGRP uses bandwidth as a metric.
* OSPF uses cost based on bandwidth as a metric.
RIP uses delay as a metric.
EIGRP uses hop count only as a metric.

13. Which two statements are true regarding the advantages of the use of static routes? (Choose two).

* increased security
reduced effort in configuring routes
* the administrator maintains control over routing
easier to implement in a growing network
reduces the chance of routing errors
increased router resource usage

14. The following line of code is displayed in a routing table:

R 209.165.201.0/24 [120/2] via 192.168.252.2, 00:00:16, S0/0/0

What can be concluded from this output?

A packet destined for host 192.168.252.2 will be forwarded out the interface connected to network 209.165.201.0/24.
* The value, 120, is used to determine the best path when a router has more than one routing protocol configured for the same destination network.
This route was manually configured using the ip route command.
192.168.252.2 is an interface on the router that produced this output.

15. What will be the result of the following commands?

ORL(config)# interface fastethernet 0/0
ORL(config-if)# ip address 172.16.3.1 255.255.255.0
ORL(config-if)# no shutdown

The 172.16.3.0 network will be routed by any dynamic routing protocol automatically.
* A routing table entry is made to the 172.16.3.0 network with a code of “C”.
A static route is required to route traffic to the 172.16.3.0 network.
The commands will be saved to the startup-configuration

16. An engineer creates a static route by entering the Router(config)# ip route 10.0.0.0 255.255.255.0 192.168.1.2 command. What can be concluded about this route?

* The administrative distance of this route is 1.
192.168.1.2 is the address of an interface on this router.
This route will display as a directly connected network in the routing table.
Packets with a destination IP address of 192.168.1.2 will be forwarded to the 10.0.0.0/24 network first.

17.

Refer to the exhibit. Router1 and Router2 are running EIGRP. All interfaces are operational and packets can be forwarded between all networks. What information will be found in the routing table for Router1?

Router1 will have 6 directly connected networks.
* The administrative distance of the route to network 172.16.0.0 will be 90.
The metric for routes to 172.16.0.0 will be 1.
The interface that is used to forward packets to 172.16.0.0 will always be the S0/1 interface.

18 The following line of code is present in the routing table:

O 10.16.1.0/27 [110/129] via 192.168.1.5, 00:00:05, Serial0/0/1

What does the number 129 indicate in this output?

* The cost for this link has a value of 129.
The clock rate on this serial interface is set to 129,000.
The next-hop router is 129 hops away from this router.
This route has been updated 129 times in this routing table.

19. A growing medium-sized manufacturing company recently began to have routing instability issues. The company uses static routes and has a mixture of over 30 Cisco and non-Cisco routers. The network administrator has decided to convert the network to dynamic routing. What characteristics of protocols should be considered in this selection process?

Distance vector routing protocols, such as RIP, converge more quickly than do link-state routing protocols.
EIGRP can be used on all of the routers in the company.
* OSPF can be used between the routers.
An exterior routing protocol, such as BGP, is recommended for growing companies.

20.

Refer to the exhibit. If RIP is the routing protocol, what is the value of the metric from router A to network 192.168.5.0/24?

* 3
4
56
624
724

21. A router learns two paths with equal metrics to a destination network via the RIP routing protocol. How will the router handle packets to the destination network?

The router will install the first route it learned into the routing table.
* The router will install both routes in the routing table and load balance between the two.
The router will put the first route in the routing table, and denote the second route as a backup route.
The router will pick the path with the higher bandwidth and will place it in the routing table

CCNA Exploration 4.0: Routing Protocols and Concepts – Chapter 2 Exam Answers

CCNA Exploration 4.0: Routing Protocols and Concepts – Chapter 7 Exam Answers

1.

Refer to the exhibit. If all routers are running RIP version 2, why is there no route for the 192.168.1.32/27 network?
Rip version 2 does not send subnet masks in its updates.
Router A is not setup with RIP as a routing protocol.
* Rip version 2 will auto summarize routes by default.
Router B is not setup to advertise the 192.168.1.64/30 network.

2.

Refer to the exhibit. Which two statements are true? (Choose two.)

* Router1 will install a route to 192.168.0.0/20
Router1 will install a route to 192.168.0.0/24
Router1 will install a route to 192.168.16.0/24
Router2 will install a route to 192.168.16.0/24
* Router2 will not install a route to 192.168.16.0/20

3.

Refer to the exhibit. Which command on which router will allow Router1 to learn about the 192.168.0.0/20 network?
Router1(config)# ip classless
Router1(config-router)# no passive-interface serial 0/1/1
* Router2(config-router)# version 2
Router2(config-router)# neighbor 10.0.0.2

4. What are two reasons to implement RIP version 2 rather than RIP version 1? (Choose two.)
* RIP version 2 supports VLSM.
RIP version 2 supports more than 16 routers.
RIP version 2 supports classful (and not classless) routing
* RIP version 2 supports routing update authentication.
RIP version 2 supports multi-areas.
RIP version 2 uses the Dijkstra algorithm rather than the Bellman-Ford algorithm.

5. How are RIP v1 and RIP v2 similar to one another? (Choose three.)
* They both use hop count as a metric.
* They both have the same metric value for infinite distance.
They both broadcast their updates to their neighbors.
They both send subnet mask information in their updates.
They both provide for authentication of update sources.
* They both use split horizon to prevent routing loops.

6.

Refer to the exhibit. Routers East and West are configured using RIPv1. Both routers are sending updates about their directly connected routes. The East router can ping the West router serial interface and West can ping the serial interface of East. However, neither router has dynamically learned routes from the other. What is most likely the problem?

A gateway of last resort is required.
Subnetting is not supported by RIPv1.
* VLSM is not supported by RIPv1.
One of the routers needs a clock rate on the serial interface.

7.

Refer to the exhibit. Which command will allow Router2 to learn about the 192.168.16.0/28 network?
Router1(config)# ip classless
* Router1(config-router)# network 192.168.16.0
Router1(config-router)# no passive-interface serial 0/1/1
Router2(config-router)# version 2
Router2(config-router)# neighbor 10.0.0.2

8.

Refer to the exhibit. All routers are running RIP version 2. JAX is configured to just advertise the 10.0.0.0/24 network. CHI is configured to advertise the 172.16.0.0/16 network. A network administrator enters the commands shown in the exhibit. What changes will occur in this network?

The JAX router will ignore updates for the 172.16.0.0/16 network due to split horizon issues.
* The CHI router will install a route to the 192.168.0.0/16 network in its routing table.
The routing table for CHI will have the 192.168.0.0/16 route but it will have an S next to the route.
The ORL router will apply a 255.255.0.0 subnet mask to all networks in the routing updates it forwards.

9.

Refer to the exhibit. A technician needs to add a new loopback interface to test routing functionality and network design. The technician enters the following set of commands on the router:
Sanford(config)# interface loopback1
Sanford(config-if)# ip address 192.168.6.62 255.255.255.252

Why does the router respond with an error?

The router does not allow loopback interface configurations.
This mask can not be used with this class of addresses.
Classless routing must be configured before this address can be added.
* The network address for Loopback1 overlaps with an already configured interface address.
The router is over the limit for the maximum paths that can be provided in the routing table.

10. What is the maximum network diameter permitted by the default metric of RIPv2?
*15 hops
16 hops
100 hops
120 hops
255 hops

11. What are two functions of the network command used when configuring routing protocols? (Choose two.)
* identifies which networks will be included in the routing updates
identifies the hosts addresses that can be summarized in the network
used to list all addresses for remote and local networks
determines which subnet mask to apply to routing updates
* determines which interfaces can send and receive routing updates

12.

Refer to the exhibit. What can be concluded from the output shown in the exhibit?
The routing table is limited to 2 routes.
The LAN interfaces are participating in the routing process.
One update has been sent out of each serial interface and 2 have been received.
* The no auto-summary has not been configured on this router.

13. A network administrator has been told that the company IP address infrastructure must adhere to RFC 1918. What three IP address ranges from RFC 1918 could the administrator use on the network? (Choose three.)
* 10.0.0.0/8
127.0.0.0/8
169.254.0.0/16
* 172.16.0.0/12
* 192.168.0.0/16
209.165.201.0/27

14.

Refer to the exhibit. All routers are running RIPv1. What changes will occur in the routing table of router B if a loopback interface with an address of 10.16.1.129/27 is configured on router B?

Routes to the 10.16.1.0/27, 10.16.1.64/27, and 10.16.1.128/27 networks are added.
* A connected route to the 10.16.1.128/27 network is added.
A third route to the 10.0.0.0/8 network with RIPv1 as the source is added.
The 10.0.0.0/8 route is dropped immediately from the routing table after router B is configured.

15. A network administrator installed four new routers that are running RIPv2. Router1 is a boundary router in the RIPv2 network and has a default route configured. Once the network has converged, the network administrator enters Router1(config-router)# defaultinformation originate on Router1. How will this affect the network?

prevents Router1 from forwarding updates about networks that are not directly connected
causes all routers in the network to synchronize routing updates with Router1
forces Router1 to become the primary or designated router (DR) for updates
* propagates the default route to all routers in the network

16.

Refer to the exhibit. The exhibited network contains a mixture of Cisco and non-Cisco routers. The command debug ip rip was entered on the JAX router. All routers are running the same version of RIP. Router CHI and Router ORL are not able to reach the 192.168.1.16/28 network. What is a possible solution to this problem?

Enable split horizon in the network.
* Configure RIPv2 on routers.
Add network 192.168.1.0 to the RIP configuration on the JAX router.
Configure JAX Fa0/0 as a passive interface.
Enable the Serial0/0/0 interface on the JAX router.
Change the IP address on the Fa0/0 interface of the JAX router to 192.168.1.1/24.

17. What field was added to the RIP message header by RFC 1723 to add support for VLSM and CIDR?
* subnet mask
destination port number
address family identifier
source and destination IP addresses

18.

Refer to the exhibit. What effect will the commands that are shown have on RIP updates for Router1?
Only version 2 updates are sent to 255.255.255.255.
* Only version 2 updates are sent to 224.0.0.9.
Both version 1 and version 2 updates are sent to 224.0.0.9.
Both version 1 and version 2 updates are sent to 255.255.255.255.

19.

Refer to the exhibit. RIPv1 is configured as the routing protocol for the network that is shown. The following commands are used on each router:
router rip
network 10.0.0.0
network 172.16.0.0

When this configuration is complete, users on the LAN of each router are unable to access the remote LANs. Why?

The network statements are configured incorrectly.
A routing loop has been created.
* RIPv1 is unable to route to discontiguous subnets of a major network.
RIPv1 is unable to route networks with a /24 subnet mask.

20. RIPv2 is the configured routing protocol on the routers in a network. The command Router(config-router)# no version 2 is entered on the routers. What effect does entering this command have on routing updates?

Subnet masks will be added to the routing updates.
Routing updates will be sent out using multicast address 224.0.0.9.
* Version 1 and 2 updates will be received and the version 2 updates will not be sent.
The RIP routing process will be removed from the router and routing updates will not be forwarded.

CCNA Commands

IP ROUTING

#sh ip route – To view IP routing tables created on a Cisco router.

-Static Routing- Routers are manually configured for networks that are not directly connected, to be able to route to all networks via the next-hop interface.

Example- Let 192.168.30.0/24 be the IP of a network not directly connected
Let 192.168.20.2 be the next hop interface

(config)#ip route 192.168.30.0 255.255.255.0 192.168.20.2

-to remove static route
(config)#no ip route 192.168.30.0 255.255.255.0 192.168.20.2

-Default Routing- Used on stub networks only to send packets with remote destination network not in the routing table to the next hop router.

(Assume IP 192.168.40.1 is not in routing table)

-first remove static route
(config)#no ip route 192.168.30.0 255.255.255.0 192.168.40.1
(config)#ip route 0.0.0.0 0.0.0.0 192.168.40.1

-RIP-A distance vector routing protocol that passes complete routing table contents to neighbouring routers

Example- Let 192.168.10.0 & 192.168.20.0 be directly connected networks of a router interfaces and 192.168.30.0 be non-directly connected

-first delete all static routes
(config)#no ip route 192.168.30.0 255.255.255.0 192.168.20.2
(config)#router rip
(config-router)#192.168.10.0
(config-router)#192.168.20.0
(config-router)#^z
#

-Verifying RIP
1.Sh ip route
2.debug ip

-Holding Down RIP Propagation-To stop RIP update sending but allow its receipt
-say for s0/0 with ip 192.168.10.0

(config)#router rip
(config-router)#network 192.168.10.0
(config-router)#passive-interface serial 0/0

-IGRP-Also a distance routing protocol
Example- Let 192.168.10.0 & 192.168.20.0 be directly connected networks of a router interfaces with autonomous system number of 10 and 192.168.30.0 be non-directly connected

#router igrp 10
(config-router)#network 192.168.10.0
(config-router)#network 192.168.20.0
(config-router)#^z
#

-Verifying IGRP
1.sh ip route
2.sh protocols- Displays routed protocols and their interfaces
3.sh ip protocols- Displays routing protocols configured
4.debug igrp events- Displays summary of IGRP routing information running on the network
5.debug igrp transactions- Displays messages request from neighbour routers

-Turning off all possible debugging
#un all

-EIGRP-Uses classless routing which is subnet mask information sent with routing protocol updates.

Example- Let 192.168.10.0 & 192.168.20.0 be directly connected networks of a router interfaces with autonomous system number of 20 and 192.168.30.0 be non-directly connected

#router eigrp 20
(config-router)#network 192.168.10.0
(config-router)#network 192.168.20.0
(config-router)#^z

-To stop EIGRP from working on an interface-no sending no receipt
(config)#router eigrp 20
(config-router)#passive-interface serial 0/0

-To enable EIGRP on discontiguos networks(two different subnetworks of classfull network connected by another different classful subnetwork)
Example- Let 172.16.0.0 & 10.0.0.0 be directly connected to a router to another remote subnetwork of 192.168.10.0, then to enable EIGRP, we use

(config)#router eigrp 100
(config-router)#network 172.16.0.0
(config-router)#network 10.0.0.0
(config-router)#no auto-summary
N.B-The no auto-summary command sholuld be enabled in routers that encloses such networks.

-Verifying EIGRP
1. sh ip route- Shows entire routing table
2. sh ip route eigrp- Shows only EIGRP entries in the routing table
3. ip eigrp neighbours- Shows all EIGRP neighbours
4. ip eigrp topology- Shows entries in the EIGRP topology table

OSPF- A link-state routing protocol

Example- Let 10.0.0.0 be the network directly connected to the router upon which OSPF is to be enabled; with ospf ID of 1 and area o

(config)#router ospf 1
(config-router)#network 10.0.0.0 0.255.255.255 area0

-Loopback Interface- They are configured to be used as the routers RID to advertise the routes and elect DR and BDR.

Example- Let the loopback iinterface be configured on interface with ip 172.16.10.1

(config)#int loopback 0
(config-if)#ip address 172.16.10.1 255.255.255.0
(config-if)#no shut
(config-if)#^z

-Verifying OSPF Configuration
1. sho ip ospf- Used to display all OSPF information
2. sho ip ospf database- indicates the number of links and neighboring router ID
3. sho ip ospf interface- Displays all OSPF interface related info
4. sho ip ospf neighbour- Summarizes OSPF info about neighbours
5. sho ip protocols- Overview of all present running protocols

- Verifying Loopback and RID
1. sho running-config- To verify loopback address
2. sho ip ospf database- Verifies the new RID of each router
3. sho ip ospf interface- Verifies the new RID of each router

-Initial configuration of a 1900 Switch with ip 172.16.10.16

>en
#config t
(config)#enable password level 1 kennifeh
(config)#enable password level 15kennifeh 1
(config)#enable secret kennifeh 2(when enabled no need 4 enable password)
(config)#hostname kenn 1900
(config)#ip address 172.16.10.16 255.255.255.0
(config)#ip default-gateway 172.16.10.1
(config)#int f0/1
(config-if)#description Finance_vlan (No space for 1900)
(config-if)#int f0/26
(config-if)#description Trunk_to_Biulding
(config-if)#exit
(config)#

-Initail Configuration of 2950 Switch with ip 172.16.10.17 255.255.255.0

>en
#config t
(config)#hostame kenn2950
(config)#enable password kenn
(config)#enable password kenn1(enable and enable secret password must be different)
(config)#line vty 0 15
(config-line)#login
(config-line)#password telnet
(config-line)#line con 0
(config-line)#login
(config-line)#password console
(config-line)#exit
(config)#int vlan 1
(config-if)#ip address 172.16.10.17 255.255.255.0
(config-if)#no shut
(config-if)#int f0/1
(config-if)#description sales printer(with space)
(config-if)#int f0/12
(config-if)description connection to backbone
config-if)#exit
(config)#ip default-gateway 172.16.10.1
(config)#

-Erasing Switching Configuration 1900

#delete nvram
yes

-Erasing Switching Configuration 2950

#erase startup-config
Enter

-Configuring VLANS 1900

>en
#config t
(config)#vlan 2 name Cisco
(config)#vlan 3 name Microsoft
(config)#vlan 4 name Comptia
(config)#exit

verify with command sh run

-Configuring for 2950

>en
#vlan database
(vlan)#vlan 2 name Cisco
(vlan)#vlan 3 name Microsoft
(vlan)#vlan 4 name Comptia
(vlan)#apply
(vlan)#^c

verify with command sh vlan brief

-Assigning Switch Ports To Vlan-1900

(config)#int e0/2
(config-if)#vlan-membership static 2
(config-if)#int e0/3
(config-if)#vlan-membership static 3
(config-if)#exit

verify with sh vlan

-Assigning Switch Ports To Vlan-2950

(config)#int f0/2
(config-if)#switchport access vlan 2
(config-if)#int f0/3
(config-t)#switchport access vlan 3
(config-if)#int f0/4
(config-if)#switchport access vlan 4
(config-if)#

verify with sh vlan brief

-Configuring Trunks ports

(config)#int f0/26
(config-if)#trunk on

-Configuring Trunk Ports for 2950

(config)#int f0/12
(config-if)#switchport mode trunk
(config-if)#^z
#

-To disable Trunk use- switchport mode access

-To verify Trunking use sh running config

-Configuring Inter-vlan Routing for 1900 connecting to 2600

(config)#int f0/0.1
(config-if)#encapsulation isl vlan (d number)

-Configuring Inter-vlan Routing for 2950 connecting to 2600

(config)#int f0/0.1
(config-if)#encapsulation dot1q vlan (d number)
-Configuring VTP for 1900

(config)#vtp server
(config)vtp domain kenn
(config)#vtp password kenn

-Configuring VTP for 2950

(config)#vtp mode server
(config)#vtp domain routersim
(config)#^z

-verify with sh vtp status

-Checking the Current Configuration Register Values

show version or show ver

-Changing Configuration Register

(config)#config-register 0×101 (d default is 0×2102)
(config)#^z

-Recovering Passwords

-1. Interrupt the Router Boot Sequene
ctrl+Break key (windows wont perform break key, only 95/98)

-2. Changing the configuration register
-for 2600 series router
rammon>confreg 0×2142

-for 2500
type 0 after a break and enter the command o/r 0×2142

-3. Reloading the Router and Entering Privilged mode
-for 2600-type reset
-for 2500-type I

-4. Viewing and changing the configuration
-copy run start

-5. Resetting the configuration Register and Reloading the Router
-config t
-config-register 0×2102
-copy run start-to save

-Backing up and restoring the Cisco ios

-1. verifying flash memory-Ensuring flash memory has enough room
router#sh flash

-2. Backing-up the ciso ios
first verify server connectivity by- Router#ping 192.168.0.120
then; router#copy flash tftp
-3. Restoring or upgrading the cisco router ios
router#copy tftp flash
[confirm][ENTER]
?[ENTER]

-Backing up and Restoring the Cisco configuration

1.Backing up the cisco router configuration
-copy runing config tftp

2. verifying the current configuration
-sh run

3. copying the current cofiguration to NVRAM
-copy run start

4. copying the current configuration to a TFTP server
-copy run TFTP

5. Restoring the Cisco Router Configuration
-copy TFTP run

6. Erasing the configuration
-erase startup-config

-Getting CDP timers and Holdtime information
Router#config t
Router(config)#cdp timer 90
Router(config)#cdp holdtime 240
Router(config)#^z

-To turn-off CDP Completely-no cdp run

-Gathering Neighbour information
kenn2509#sh cdp nei- delivers information about directly connected devices
OR kenn2509#sh cdp neighbour detail Also sh cdp entry

-Gathering Interface Traffic Information
kenn2509#sh cdp traffic

-Gathering port and Interface information
kenn2509#sh cdp interface

-To turn off cdp on a router, use
no cdp enable then ^z

-Using Telnet
kenn2509#telnet 172.16.10.2

-Telnetting into multiple devices simultaneously
kenn2509#telnet 172.16.10.2
then, 2501B>{cntl+shift+6, then x}

-checking Telnet connections
kenn2509#sh sessions-connections from your router to remote

-checking Telnet users
kenn2509#sh user

-closing Telnet sessions
1900switch>exit OR
kenn2509#disconnect1 (num of active networks)

-Resolving Hostname
kenn2509#config t
kenn2509(config)#ip host 2501B 172.16.10.2
kenn2509(config)#ip host 1900switch 192.168.0.148
kenn2509(config)#^z

-To remove a hostname from a table, use
RouterA(config)#no ip host routerB

-Using DNS to resolve names

#config t
(config)#ip domain-lookup (usually turned on by default)
(config)#ip name-server 192.168.0.70 (ip of an assumed DNS set)
(config)#ip domain-name kenn.com (Appends the domain name to a host)
(config)#^z

-Check Network Connectivity
use ping command
#ping kenn2509

-Using Traceroute command
#trace 2501B

-Creating a Standard Access Lists (1-99 or 1,300-1,999)

(config)#access-list 10 deny 172.16.30.2 (using the ip as a test)

-Controlling vty(Telnet) sessions

(config)#access-list 50 permit 172.16.30.2
(config)#line vty 0 4
(config-line)#access-class 50 in

-Creating Extended Access-lists (100 to 199) OR (2000 to 2699)

(config)#access-list 110 deny tcp any host 172.16.30.2 eq 23 log
(config)#access-list 110 permit ip any any
(config)#int f0/0
(config-if)#ip access-group 110 in
(config-if)#ip access-group 110 out

source : Shadikov