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The CCNA/ICND1 courses split here.
121. Introduction
https://www.udemy.com/course/ccna-complete/learn/lecture/7840926#overview
122. RIP the Routing Information Protocol
Overview
- Distance Vector routing protocol
- Metric: Hop Count
- Max hop count = 15
- Equal cost Multi Path for up to 4 paths by default
RIPv2 vs RIPv1
- v1 legacy. Still supported but not used.
- Does not send subnet mask info so VLSM is not supported
- OK to use /28 or some other, but all subnets must use the same mask.
- Sends updates every 30 sec. (broadcast?)
- Does not support authentication
- Does not send subnet mask info so VLSM is not supported
- v2
- Supports VLSM
- Uses Multicast address 224.0.0.9
- Supports authentication
- Both routers must have matching passwords
RIPng
- Supports IPv6
- Not covered on CCNA
RIPv2 Configuration
router rip version 2 network 10.0.0.0
- Network is classical, so no mask is specified
Summarization
Auto-Summary
- RIP automatically summerizes routs on classful boudaries (Class A, B C, …)
- 192.168.10.1/30 will be advertised as 192.168.10.0/24
- 172.16.10.1/30 will be 172.16.0.0/16
- This can cause ‘black holes’ and is almost NEVER desireable, so turn auto-summary off
router rip no auto-summary
Manual Summary
- Applied on the interface
- Allows you to set a subnet mask to summarize what you want
- Set this on the interface SENDING the information
R2 (config)# interface fastEthernet 1/0 ip summary-address rip 10.0.0.0 255.255.0.0
Verify Router Protocols
R1#show ip protocols *** IP Routing is NSF aware *** Routing Protocol is "rip" Outgoing update filter list for all interfaces is not set Incoming update filter list for all interfaces is not set Sending updates every 30 seconds, next due in 16 seconds Invalid after 180 seconds, hold down 180, flushed after 240 Redistributing: rip Default version control: send version 2, receive version 2 Interface Send Recv Triggered RIP Key-chain FastEthernet0/0 2 2 FastEthernet0/1 2 2 Automatic network summarization is not in effect Maximum path: 4 Routing for Networks: 10.0.0.0 Routing Information Sources: Gateway Distance Last Update 10.1.0.1 120 00:00:11 10.0.0.1 120 00:00:17 Distance: (default is 120)
RIP Database
#sh ip rip database
10.0.0.0/8 auto-summary
10.0.0.0/24 directly connected, FastEthernet0/0
10.0.1.0/24
[1] via 10.0.0.1, 00:00:21, FastEthernet0/0
10.0.2.0/24
[1] via 10.0.0.1, 00:00:21, FastEthernet0/0
10.1.0.0/24 directly connected, FastEthernet0/1
10.1.1.0/24
[1] via 10.1.0.1, 00:00:15, FastEthernet0/1
Default Route Injection
Use this to inject a default route to all routers without having to manually configure each one.
- Only used on egress router
R4(config)# ip route 0.0.0.0 0.0.0.0 203.0.113.2 router rip default-information originate
* Note: Removed R5 from setup below
R1#show ip route
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2
i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
ia - IS-IS inter area, * - candidate default, U - per-user static route
o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP
+ - replicated route, % - next hop override
Gateway of last resort is 10.0.0.2 to network 0.0.0.0
R* 0.0.0.0/0 [120/3] via 10.0.0.2, 00:00:24, FastEthernet0/0
10.0.0.0/8 is variably subnetted, 4 subnets, 2 masks
C 10.0.0.0/24 is directly connected, FastEthernet0/0
L 10.0.0.1/32 is directly connected, FastEthernet0/0
R 10.1.0.0/24 [120/1] via 10.0.0.2, 00:00:24, FastEthernet0/0
R 10.1.1.0/24 [120/2] via 10.0.0.2, 00:00:24, FastEthernet0/0
Passive Interfaces
- Passive interfaces are used to receive routing information but not send any.
- Generally used on interfaces that connect to networks not owned by your organization.
conf t router rip passive-interface f3/0
123. RIP Lab Demo
Setup RIP all routers
conf t router rip version 2 no auto-summary network 10.0.0.0 end
Configure Summary Routes on R2 and R5
R2
conf t int f1/0 ip summary-address rip 10.0.0.0 255.255.0.0 int f0/0 ip summary-address rip 10.1.0.0 255.255.0.0
R5
conf t int f2/0 ip summary-address rip 10.0.0.0 255.255.0.0 int f3/0 ip summary-address rip 10.1.0.0 255.255.0.0
Configure the default route (Default Route Injection)
Enter Global Configuration mode on R4 only
R4#conf t
Configure the route
ip route 0.0.0.0 0.0.0.0 203.0.113.2
Add the default route to the routing protocol
router rip default-information originate
Set Interface FastEthernet 3/0 as Passive AND accept routing information about the 203.0.113.0 network
router rip passive-interface f3/0 network 203.0.113.0
124. EIGRP – the Enhanced Interior Gateway Routing Protocol
Characteristics
- Supports large networks
- Fast convergence
- Network topology changes only sent to affected routers.
- Multicast
- Equal cost load balancing up to 4 by default but can increase to 16
- Can be manually configured to perform unequal cost load balancing
Configuration
conf t
router eigrp <NUMBER>
network 10.0.0.0 0.0.255.255
- <NUMBER> is the Autonomous System (AS), an independent administration domain.
- EIGRP routers must have the same AS number to peer with each other.
Wild Card Masks
Note to self: Wild card masks say “I don’t care about these bits. If the value is 0, then I don’t care, but if it is a 1, then I do. This helps mask out the Network portion (portion I do care about) vs the Host portion (portion I do not care about.)
- To determine the wild card mask, subtract each value in the subnet mask from 255.
- A subnet with a mask of 255.255.255.240 would have a wild card mask of 0.0.0.15
- Not using a wild card mask will default to using the classical boundary (Class A, B, C, etc.)
- Class A: 0.255.255.255
- Class B: 0.0.255.255
- Class C: 0.0.0.255
Network
- The Network command:
- “look for interfaces that have IP addresses that fall within this range
- Enable EIGRP on those interfaces
- Send out and listen for EIGRP hello messages, and peer with adjacent EIGRP routers
- Advertise the network and mask which is configured on those interfaces.
- network 10.0.0.0 0.255.255.255
- 10.1.0.0/24
- 10.0.1.0/24
- 10.0.2.0/24
- 10.0.0.0/8 NOT ADVERTISED!
- network 10.0.0.0 0.0.255.255
- 10.0.1.0/24
- 10.0.2.0/24
- 10.1.0.0/24 NOT ADVERTISED!
- network 10.0.0.0 0.255.255.255
- To match a single IP
- network IP.ADD.RE.SS 0.0.0.0
Router Identification
- Routers are “identified” by:
- The Loopback IP or EIGRP ID (Also IPv4)
- One of these is best practice
- Loopbacks never go down, so are best of the best
- If neither of the above are configured. the highest IP address of any configured interface will be used.
- The Loopback IP or EIGRP ID (Also IPv4)
- Can see the Router-ID using show ip protocols
- If EIGRP has already been started and you change the Router-ID, you will need to restart EIGRP on that router to update the Router-ID
Manually setting the Router-ID
- Needs to be in the form on an IPv4 address
- Does NOT need to be an IP address on the router since it is NOT an IP address
- This is not best practice since it could get confusing.
conf t router eigrp <NUMBER> eighrp router-id IP.ADD.RE.SS
125. EIGRP Lab Demo
Commands
View all configurations
- This includes configurations made directly on interfaces also
show run | section eigrp
View configurations on Interfaces only
show ip eigrp interfaces
View neighbors
- This will confirm you have communication with other routers
show ip eigrp neighbors
126. IGP Lab Exercises
RIP Configuration
1) Enable RIPv2 on every router. Ensure all networks except 203.0.113.0/24
are advertised. Do not perform any summarisation.
conf t router rip version 2 network 10.0.0.0 no auto-summary end
2) Verify all networks are in the router’s routing tables.
show ip route
3) Verify that routing is working by checking that PC1 has connectivity to
PC3.
C:\> ping 10.1.2.10 Packets: Sent = 4, Received = 3, Lost = 1 (25% loss),
4) Ensure that all routers have a route to the 203.0.113.0/24 network.
Internal routes must not advertised to the Service Provider at 203.0.113.2.
R4#conf t router rip network 203.0.113.0 default-information originate passive-interface f1/1 end
5) Verify that all routers have a path to the 203.0.113.0/24 network.
R1#ping 203.0.113.1 !!!!!
6) Configure a default static route on R4 to the Internet via the service
provider at 203.0.113.2
conf t ip route 0.0.0.0 0.0.0.0 203.0.113.2 130
7) Ensure that all other routers learn via RIP how to reach the Internet.
sh ip route
8) Verify all routers have a route to the Internet.
Note: There is no return path from 203.0.113.2, so those pings/traceroutes will fail.
R1# ping 203.0.113.1
EIGRP Configuration
9) Enable EIGRP AS 100 on every router. Ensure all networks except
203.0.113.0/24 are advertised in EIGRP.
conf t router eigrp 100 network 192.168.0.0 0.0.0.255 end
R1#show ip protocols ... Routing for Networks: 10.0.0.0
10) Verify the routers have formed adjacencies with each other.
sh ip eigrp neighbors
11) Which routing protocol (RIP or EIGRP) do you expect routes to the
10.x.x.x networks to be learned from in the routing tables?
EIGRP because it has the lower Administrative Distance.
12) Do you expect to see any routes from the other routing protocol in the
routing tables?
Should still see the default route and 203.0.113.0 networks via RIP
13) View the routing tables to verify your answers.
sh ip route <confirmed>