Auto-RP
Cisco devices can announce their willingness to be an RP, via cisco-rp-announce
A different service, a mapping agent, will read these messages, pick a winner, then advertise that out via cisco-rp-discovery
- 5.5.5.5, Candidate RP.
- 4.4.4.4, mapping agent.
R4# show ip pim autorp AutoRP Information: AutoRP is enabled. RP Discovery packet MTU is 1500. 224.0.1.40 is joined on Loopback0. AutoRP groups over sparse mode interface is enabled PIM AutoRP Statistics: Sent/Received RP Announce: 0/16, RP Discovery: 64/42
These packets are slow.
R4# debug ip pim auto-rp PIM Auto-RP debugging is on ! ! Sent to cisco-rp-discovery ! *Apr 25 19:57:08.940: Auto-RP(0): Build RP-Discovery packet *Apr 25 19:57:08.941: Auto-RP(0): Build mapping (224.0.0.0/4, RP:5.5.5.5), PIMv2 v1, *Apr 25 19:57:08.942: Auto-RP(0): Send RP-discovery packet of length 48 on GigabitEthernet0/3 (1 RP entries) *Apr 25 19:57:08.943: Auto-RP(0): Send RP-discovery packet of length 48 on GigabitEthernet0/4 (1 RP entries) *Apr 25 19:57:08.945: Auto-RP(0): Send RP-discovery packet of length 48 on GigabitEthernet0/0 (1 RP entries) *Apr 25 19:57:08.948: Auto-RP(0): Send RP-discovery packet of length 48 on Loopback0(*) (1 RP entries) *Apr 25 19:57:12.008: Auto-RP(0): Received RP-discovery packet of length 48, from 10.0.45.5, ignored ! ! Received by cisco-rp-announce ! *Apr 25 19:58:30.159: Auto-RP(0): Received RP-announce packet of length 48, from 5.5.5.5, RP_cnt 1, ht 181 *Apr 25 19:58:30.159: (0): pim_add_prm:: 224.0.0.0/240.0.0.0, rp=5.5.5.5, repl = 0, ver =3, is_neg =0, bidir = 0, crp = 0 *Apr 25 19:58:30.160: Auto-RP(0): Update *Apr 25 19:58:30.160: prm_rp->bidir_mode = 0 vs bidir = 0 (224.0.0.0/4, RP:5.5.5.5), PIMv2 v1 R4# undebug all All possible debugging has been turned off