Specifications

Chapter 5. IBM System Networking RackSwitch implementation 211
* 224.0.0.5 255.255.255.255 0.0.0.0 multicast addr
* 224.0.0.6 255.255.255.255 0.0.0.0 multicast addr
* 224.0.0.18 255.255.255.255 0.0.0.0 multicast addr
* 255.255.255.255 255.255.255.255 255.255.255.255 broadcast broadcast
ACC-1#
OSPFv3 configuration
OSPF version 3 is based on OSPF version 2, but is modified to support IPv6 addressing. In
most other ways, OSPFv3 is similar to OSPFv2: They both have the same packet types and
interfaces, and both use the same mechanisms for neighbor discovery, adjacency formation,
LSA flooding, aging, and so on. The administrator should be familiar with the OSPFv2
concepts covered in “OSPFv2 configuration” on page 204 before implementing the OSPFv3
differences described in this section.
Although OSPFv2 and OSPFv3 are similar, they represent independent features on the
switch. They are configured separately, and both can run in parallel on the switch with no
relation to one another, serving different IPv4 (OSPFv2) and IPv6 (OSPFv3) traffic.
OSPFv3 is designed to support IPv6 addresses. IPv6 interfaces must be configured on the
switch and assigned to OSPF areas, in much the same way IPv4 interfaces are assigned to
areas in OSPFv2. This difference is the primary configuration difference between OSPFv3
and OSPFv2.
For IPv6 interface instructions, see 5.3.2, “Basic IPv6 configuration” on page 192.
The OSPF configuration starts from the assumption that all the configuration tasks presented
so far in this chapter have been performed. All the ports are up and running, all the VLANs
are correctly defined, all the IPv6 interfaces are configured, the routers are reachable on the
Layer 3 links, and the servers can ping the default gateway.
The goal of the configuration is to enable OSPFv3, to configure the Layer 3 links in the
protocol, and to redistribute the connected networks (server subnet) to the neighbors.
The final result is that a route to SRV-1 (FC10::10/64) is installed in the AGG-1 and AGG-2
routing table, a route to SRV-3 (FC30::30/64) is installed in the ACC-1 and ACC-2 routing
table, and SRV-1 and SRV-3 are able to ping each other.
To perform a basic OSPFv3 configuration, complete the following steps. For more details and
options, see 5.5, “More information” on page 238.
1. Define the Router ID.
Where OSPFv2 uses a mix of IPv4 interface addresses and Router IDs to identify
neighbors, depending on their type, OSPFv3 configuration consistently uses a Router ID
to identify all neighbors. Although Router IDs are written in dotted decimal notation, and
might even be based on IPv4 addresses from an original OSPFv2 network configuration, it
is important to realize that Router IDs are not IP addresses in OSPFv3, and can be
assigned independently of the IP address space. However, maintaining Router IDs
consistent with any OSPFv2 IPv4 addressing allows for easier implementation of
both protocols.
The same Router IDs are used for both OSPFv2 and OSPFv3, that is, the IP addresses of
Loopback 1 interfaces.