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Configuring static link local addresses

Hi All,

Need some help from the experts that have been deploying ipv6 in production networks.

I have a few routers talking v6 to each other on an all Ethernet network. The interfaces each have a statically configured global ipv6 address in a /64 and they run OSPFv3 and BGP (ipv6). No SLAAC or DHCPv6 happening here.  Of course the router also auto assigns a LLA to each interface based on the MAC of the interface.

The routes in the network that are learned via OSPF or BGP are installed in the RIB/FIB using the link local address as their next hop ip (of course the LLA of the next hop 'interface'), and its hard to identify which LLA addresses these are, and not very practical and easy to work it, besides documentation and troubleshooting as the network grows.

So my questions are:

Q1. Is it considered best practise (or bad practise) to statically configure an LLA on each interface together with the Global Address, to resolve this issue, or is it best to leave LLA as auto assigned ?

Q2. If a static LLA is configured, then if for some reason the interface is changed due to upgrade or hardware failure, the LLA remains the same if statically configured, rather than changes if the MAC changes, so this may also be preferable approach, unless I miss something

Q3. I also installed a static route of the form "ipv6 route [global address/64] [next hop]".  In this case the next hop I use is the global v6 address of the next hop and this works fine.  Does it make any sense to use the LLA as the next hop for manually configured static network or host routes ?



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