Build the lab yourself
This lesson continues on the Edge and core lab: build that first (its Build the lab yourself section), then apply this lesson's configuration on each router. edge1 and edge2 use the same OSPFv3 configuration as core1, with their own router ID and loopback (2001:db8:100::2 and ::3) and their internal links (eth1 and eth2).
Where next
- OSPF FundamentalsPrerequisite · Beginner · 70 min
The link-state IGP that runs inside most networks: neighbour adjacencies, LSA flooding, SPF, costs, DR/BDR, areas and LSA types, a hands-on FRR lab, and how OSPF underpins BGP.
- Edge and core: building out a VyOS networkPrerequisite · Intermediate · 60 min
Split one BGP router into edge routers that face the outside world and a core that carries traffic inside: loopbacks, OSPF for infrastructure, iBGP between loopbacks, next-hop-self, and what happens when a link fails. Built and broken on three real VyOS routers.
- BGP on loopbacks vs interface addressesAlso covers OSPF · Intermediate · 45 min
Why BGP sessions between loopbacks survive link failures and use parallel links, and what they need to work: an IGP or static routes, update-source, the eBGP connected check, and BFD. Every failure is reproduced on two real VyOS routers.
- IPv4 over an IPv6-only core (RFC 8950)Also covers IPv6 · Intermediate · 40 min
Carry IPv4 routes over IPv6 BGP sessions with IPv6 next hops, so core routers need no IPv4 addresses at all. Built on VyOS: the missing router ID, what breaks without the extended next hop capability, native IPv4 on the wire, and why traceroute shows 192.0.0.8.