Dell S6000 FTOS 9.0(2.0) Configuration Guide for the System - Page 478

www.dell.com | support.dell.com Adjacencies Adjacencies on point-to-point interfaces are formed as usual, where IS-IS routers do not implement Multi-Topology (MT) extensions. If a local router does not participate in certain MTs, it will not advertise those MT IDs in its IIHs and so will not include that neighbor within its LSPs. If an MT ID is not detected in the remote side's IIHs, the local router does not include that neighbor within its LSPs. The local router will not form an adjacency if both routers don't have at least one common MT over the interface. Implementation Information IS-IS implementation supports one instance of IS-IS and six areas. The system can be configured as a Level 1 router, a Level 2 router, or a Level 1-2 router. For IPv6, the IPv4 implementation has been expanded to include two new type-length-values (TLV) in the protocol data unit (PDU) that carry information required for IPv6 routing. The new TLVs are IPv6 Reachability and IPv6 Interface Address. Also, a new IPv6 protocol identifier has also been included in the supported TLVs. The new TLVs use the extended metrics and up/down bit semantics. Multi-Topology IS-IS adds TLVs: • The Multi-Topology TLV contains one or more Multi-Topology IDs in which the router participates. This TLV is included in IIH and the first fragment of an LSP. • The MT Intermediate Systems TLV appears for every topology a node supports. An MT ID is added to the extended IS reachability TLV type 22. • The Multi-Topology Reachable IPv4 Prefixes TLV appears for each IPv4 announced by an IS for a given MT ID. Its structure is aligned with the extended IS Reachability TLV Type 236 and it adds an MT ID. • The Multi-Topology Reachable IPv6 Prefixes TLV appears for each IPv6 announced by an IS for a given MT ID. Its structure is aligned with the extended IS Reachability TLV Type 236 and add a MT ID. By default, FTOS supports dynamic hostname exchange to assist with troubleshooting and configuration. By assigning a name to an IS-IS NET address, you can track IS-IS information on that address easier. FTOS does not support ISO CLNS routing; however, the ISO NET format is supported for addressing. To support IPv6, the Dell Networking implementation of IS-IS performs the following tasks: • Advertise IPv6 information in the PDUs • Process IPv6 information received in the PDUs • Compute routes to IPv6 destinations • Download IPv6 routes to RTM for installing in the FIB • Accept external IPv6 information and advertise this information in the PDUs 456 | Intermediate System to Intermediate System