Dell PowerSwitch S4112F-ON EMC SmartFabric OS10 User Guide Release 10.5.1 - Page 615

Established Keepalive messages exchange, and after a successful receipt, the router is in the Established state. Keepalive messages continue to send at regular periods. The keepalive timer establishes the state to verify connections. After the connection is established, the router sends and receives keepalive, update, and notification messages to and from its peer. Peer templates Peer templates allow BGP neighbors to inherit the same outbound policies. Instead of manually configuring each neighbor with the same policy, you can create a peer group with a shared policy that applies to individual peers. A peer template provides efficient update calculation with a simplified configuration. Peer templates also aid in convergence speed. When a BGP process sends the same information to many peers, a long output queue may be set up to distribute the information. For peers that are members of a peer template, the information is sent to one place then passed on to the peers within the template. Martian addresses Martian addresses are invalid networks on the Internet. Martian addresses are special IPv4 and IPv6 addresses which are not routed by routing devices on the Internet. OS10 considers the following as Martian prefixes: ● 0.0.0.0/8 ● 127.0.0.0/8 ● 224.0.0.0/4 ● :: / 128 ● FF00::/8 FE80::/16 ● ::0002-::FFFF- all prefixes Route reflectors Route reflectors (RRs) reorganize the IBGP core into a hierarchy and allow route advertisement rules. Route reflection divides IBGP peers into two groups - client peers and nonclient peers. ● If a route is received from a nonclient peer, it reflects the route to all client peers ● If a route is received from a client peer, it reflects the route to all nonclient and client peers An RR and its client peers form a route reflection cluster. BGP speakers announce only the best route for a given prefix. RR rules apply after the router makes its best path decision. NOTE: Do not use RRs in forwarding paths - hierarchal RRs that maintain forwarding plane RRs could create route loops. Routers B, C, D, E, and G are members of the same AS-AS100. These routers are also in the same route reflection cluster, where Router D is the route reflector. Routers E and G are client peers of Router D, and Routers B and C and nonclient peers of Router D. Layer 3 615