IPv6 SLAAC: Missing Router Advertisement
IPv6 hosts can look partly configured even when they cannot leave the local link. This lab teaches the distinction between a link-local address and a usable SLAAC-derived address with a default gateway.
The problem
Clients and the router have link-local IPv6 addresses and the switch link is up, but clients have no global unicast address or IPv6 default route because the router interface is not advertising the intended prefix.
What you'll practice
- Read IPv6 interface addressing
- Recognize the role of router advertisements in SLAAC
- Distinguish link-local from global unicast addressing
- Verify an IPv6 default route on a client
- Test IPv6 connectivity
The topology
One IPv6-capable router serves a single switched user LAN. The simple topology makes the RA and SLAAC exchange visible without an unrelated routing protocol.
Commands to run yourself
The real diagnostic commands for this lab, copy-paste ready. Run these in the same order to reproduce the investigation on your own session.
show ipv6 interface Ethernet1/0ipconfigshow ipv6 routeTopology diagram
Frequently asked
Can a host communicate using only a link-local address?
Yes, but only on the local link. A global unicast address and default route are needed to reach other IPv6 networks.
Ready to run this lab yourself?
No setup, no image sourcing. Book a session or ask for a live demo.