This lab will test your skills, from simple iBGP and eBGP configuration to more advanced filters and route reflectors implementations.
Lab must be executed in the shown order, without fast forwarding to the next or jumping tasks.

By the end of the lab, you will have acquired a solid knowledge and consolidated your understanding of BGP theory and configuration.

Pre-requisites are CCNA / CCNP level routing configuration.

NOTES:

  • For each AS, an IGP of your choice must configured in a separate domain.
  • Each router must have a loopback0 interface configured as n.n.n.n/32, where n is the router number (R2 loopback0 is 2.2.2.2/32).
  • Each loopback0 must be routed in each AS IGP domain.
  • Link addresses are not routed by IGP in each domain.
  • BGP LAB1 Topology

TASKS

BGP sessions
  1. In each AS, configure iBGP session between loopback0 of each router.
  2. Configure eBGP sessions between following routers using link addresses:
    • R1 & R4
    • R5 & R6
  3. On R2 configure a static route for R7 LP0, and on R7 a static route for R2 LP0.
  4. Configure eBGP session between R2 & R7 LP0.
Advertise prefixes
  1. On R2, configure following loopbacks and ip addresses.
    • LP21 192.168.21.1/24
    • LP22 192.168.22.1/24
    • LP23 192.168.23.1/24
  1. On R7 configure following loopbacks and ip addresses.
    • LP71 192.168.71.1/24
    • LP72 192.168.72.1/24
    • LP73 192.168.73.1/24
  1. Announce prefixes as follows:
    • All routers loopback0 using network statement.
    • LP21 & LP71 using network statement.
    • LP22 & LP72 using redistribute command. LP23 & LP73 must not be announced (*Hint: Use route map)
Attributes manipulation
  1. On R2 ensure that you have 2 paths to 192.168.71.0/24 and 192.168.72/24, with best path via R7.
  2. Validate you can ping 192.168.71.1 & 192.168.72.1 from R2.
  3. Link R2-R7 is very congested, so you are asked to make changes so that 192.168.71.0/24 and 192.168.72/24 are best via AS6502 (*hint: Use Local preference).
  4. Why are these 2 prefixes still preferred over AS6503, how can you fix it ?
  5. On R2 modify network statement and announce LP21 with community 6501:21 and ensure you can read community as 6501:21 on R2 and R7.
  6. In AS6503 configure ingress route maps on R7 eBGP sessions increase 192.168.21.0/24 so AS path becomes 6501 6501 6501 (instead of 6501).
Route reflectors
  1. Admined down iBGP session between R1 & R2,R6&R7.
  2. On R3 remove peer session configuration towards R1 & R2.
  3. Validate R1 is no longer receiving prefixes from R2, and nor is R6 from R7.
  4. Using peer group configuration, configure R3 as route reflectors in AS6501.
  5. Using BGP templates configuration, configure R8 as route reflectors in AS6503.
Aggregation
  1. On R1 & R2, announce an aggregate for 192.168.20.0/22. Subset of this aggregate should not be advertised ( *Hint: summary only).

Watch this video for more lab demo: