A lab which configures a computer network with external border gateway protocol. Device configurations and other diagnostic information can be found in the corresponding folders.
Background information on lab concepts can be found here: https://101zh.github.io/networking/
- Purpose
- Lab Summary
- Topology
- Address Table
- Device Overview
- ICMPv4 Traceroute Across Network
- ICMPv6 Traceroute Across Network
- IPv4 Routing Table
- IPv6 Routing Table
- Copyright
The purpose of this lab is to set up 3 AS’s and use eBGP (external border gateway protocol) to route between the 3 AS’s. To complete this lab, one needs to know how to redistribute routes between gateway protocols and routing protocols, create address-families, and declare eBGP neighbors. And although not central to the eBGP, one still must have the skills needed to set up networks with routing protocols, including advertising interfaces, subnetting, and debugging.
In this lab 3 AS’s were set up with eBGP connecting the 3 AS’s together. There are two host devices that are PCs and there are six 4321 routers that are connected via ethernet. To allow host devices to communicate with each other, the routers needed IPv6 and IPv4 routes to redistribute in and out of eBGP.
These are the topologies for both IPv4 and IPv6, each link is labeled with the network number and subnet mask of the link. Then each interface is labeled with the last octet or hextet of the usable IPv4/IPv6 address within the subnet of that link.
Additionally, the PCs can have any IP that is within the subnet of the link that they are on. DHCP is not setup.
| Device Name | Interface | IPv6 Address | IPv4 Address | Subnet Mask |
|---|---|---|---|---|
| R1 | G0/0/0 | 1:20::1/64 | 10.0.20.1 | 255.255.255.0 |
| R1 | G0/0/1 | 1::1/64 | 10.0.0.1 | 255.255.255.0 |
| R2 | G0/0/0 | 1::2/64 | 10.0.0.2 | 255.255.255.0 |
| R2 | G0/0/1 | 2::1/64 | 192.168.0.1 | 255.255.255.0 |
| R3 | G0/0/0 | 2::2/64 | 192.168.0.2 | 255.255.255.0 |
| R3 | G0/0/1 | 1:1::1/64 | 10.0.-1 | 255.255.255.0 |
| R4 | G0/0/0 | 1:1::2/64 | 10.0.-2 | 255.255.255.0 |
| R4 | G0/0/1 | 2:1::1/64 | 192.168.-1 | 255.255.255.0 |
| R5 | G0/0/0 | 2:1::2/64 | 192.168.-2 | 255.255.255.0 |
| R5 | G0/0/1 | 1:3::1/64 | 10.0.3.1 | 255.255.255.0 |
| R6 | G0/0/0 | 1:3::2/64 | 10.0.3.2 | 255.255.255.0 |
| R6 | G0/0/1 | 1:30::1/64 | 10.0.30.1 | 255.255.255.0 |
This Topology Consists of...
- Six 4321 routers running Cisco IOS XE Software, Version 16.9 Universal K9
C:\>tracert 10.0.30.2
Tracing route to DESKTOP-43DJSK3 [10.0.30.2]
over a maximum of 30 hops:
1 3 ms <1 ms <1 ms 10.0.20.1
2 <1 ms <1 ms <1 ms 10.0.0.2
3 <1 ms 1 ms <1 ms 192.168.0.2
4 <1 ms <1 ms <1 ms 10.0.1.2
5 <1 ms <1 ms <1 ms 192.168.1.2
6 1 ms 1 ms 1 ms 10.0.3.2
7 1 ms <1 ms 1 ms DESKTOP-43DJSK3 [10.0.30.2]
Trace complete.
C:\>tracert 1:30::2
Tracing route to 1:30::2 over a maximum of 30 hops
1 <1 ms <1 ms <1 ms 1:20::1
2 1 ms <1 ms <1 ms 1::1
3 1 ms <1 ms <1 ms 2::2
4 1 ms 1 ms <1 ms 1:1::2
5 1 ms <1 ms 1 ms 2:1::2
6 1 ms 1 ms 1 ms 1:3::2
7 1 ms 1 ms 1 ms 1:30::2
Trace complete.
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
a - application route
+ - replicated route, % - next hop override, p - overrides from PfR
Gateway of last resort is not set
10.0.0.0/8 is variably subnetted, 7 subnets, 2 masks
C 10.0.0.0/24 is directly connected, GigabitEthernet0/0/1
L 10.0.0.1/32 is directly connected, GigabitEthernet0/0/1
O E2 10.0.1.0/24 [110/10] via 10.0.0.2, 01:07:00, GigabitEthernet0/0/1
O E2 10.0.3.0/24 [110/10] via 10.0.0.2, 01:06:30, GigabitEthernet0/0/1
C 10.0.20.0/24 is directly connected, GigabitEthernet0/0/0
L 10.0.20.1/32 is directly connected, GigabitEthernet0/0/0
O E2 10.0.30.0/24 [110/10] via 10.0.0.2, 01:06:30, GigabitEthernet0/0/1
O 192.168.0.0/24 [110/2] via 10.0.0.2, 01:09:00, GigabitEthernet0/0/1
O E2 192.168.1.0/24 [110/10] via 10.0.0.2, 01:06:30, GigabitEthernet0/0/1
R1#show ipv6 route
IPv6 Routing Table - default - 9 entries
Codes: C - Connected, L - Local, S - Static, U - Per-user Static route
B - BGP, R - RIP, I1 - ISIS L1, I2 - ISIS L2
IA - ISIS interarea, IS - ISIS summary, D - EIGRP, EX - EIGRP external
ND - ND Default, NDp - ND Prefix, DCE - Destination, NDr - Redirect
O - OSPF Intra, OI - OSPF Inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2, a - Application
C 1::/64 [0/0]
via GigabitEthernet0/0/1, directly connected
OE2 1:1::/64 [110/10]
via FE80::CE7F:76FF:FE6A:B5E0, GigabitEthernet0/0/1
OE2 1:3::/64 [110/10]
via FE80::CE7F:76FF:FE6A:B5E0, GigabitEthernet0/0/1
C 1:20::/64 [0/0]
via GigabitEthernet0/0/0, directly connected
L 1:20::1/128 [0/0]
via GigabitEthernet0/0/0, receive
OE2 1:30::/64 [110/10]
via FE80::CE7F:76FF:FE6A:B5E0, GigabitEthernet0/0/1
O 2::/64 [110/2]
via FE80::CE7F:76FF:FE6A:B5E0, GigabitEthernet0/0/1
OE2 2:1::/64 [110/10]
via FE80::CE7F:76FF:FE6A:B5E0, GigabitEthernet0/0/1
L FF00::/8 [0/0]
via Null0, receive
MIT License
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