RSVP neighbor and RSVP session flaps are seen between MX nodes running Junos 16.x and 17.x.
Two nodes have periodic RSVP neighbor flaps:
16.1R4-S2.2 <> 17.4R3-S1.2 router-A <> Router-B 172.27.15.194 <> 172.27.15.198
On Junos 16.x, the neighbor state is recorded as Up/Down count. The Rx message count is less than Tx msgcount. On Junos 17.x, the neighbor state stays in Idle state and times out before repeating. The Rx message count is less than Tx msg count The session " 172.27.15.198:dt-rsvp-FULL-MESH " shows flap.
172.27.15.198:dt-rsvp-FULL-MESH
router-A> show rsvp neighbor RSVP neighbor: 6 learned Address Idle Up/Dn LastChange HelloInt HelloTx/Rx MsgRcvd 172.27.15.198 0 18252/18251 2:48 9 411680/365039 0 172.27.15.199 0 18252/18251 2:27 9 412155/365412 0 ==== Address: 172.27.15.198 status: Up (Remote Node neighbor) Last changed time: 2:46, Idle: 0 sec, Up cnt: 18254, Down cnt: 18253 Message received: 0 Hello: sent 411725, received: 365079, interval: 9 sec Remote instance: 0xd52a1105, Local instance: 0x24cbd7b Refresh reduction: operational Remote end: enabled, Ack-extension: enabled Enhanced FRR: Enabled LSPs (total 2): Phop 0, PPhop 0, Nhop 0, NNhop 2 ==== router-B> show rsvp neighbor RSVP neighbor: 6 learned Address Idle Up/Dn LastChange HelloInt HelloTx/Rx MsgRcvd 172.27.15.194 1:35 0/0 1:35 9 1227342/746585 0 172.27.15.195 1:10 0/0 1:13 9 1366996/885661 50 router-B> show rsvp neighbor detail RSVP neighbor: 6 learned Address: 172.27.15.194 status: Down (Remote Node neighbor) Last changed time: 2:58, Idle: 2:55 sec, Up cnt: 0, Down cnt: 0 Message received: 0 Hello: sent 1227331, received: 746585, interval: 9 sec Remote instance: 0x0, Local instance: 0xd52a1105 Refresh reduction: not operational Remote end: disabled, Ack-extension: disabled Enhanced FRR: Disabled
Output shows node hellos are enabled by default:
router-A> show rsvp version Resource ReSerVation Protocol, version 1. rfc2205 RSVP protocol: Enabled R(refresh timer): 1200 seconds K(keep multiplier): 3 RSVP Node-ID based Hello: Enabled RSVP Hello acknowledgements: Enabled Preemption: Normal Soft-preemption cleanup: 30 seconds Graceful deletion timeout: 30 seconds
Node hello’s are enabled by-default from Junos 16.1 which is formed between the loopback of PLR and merge point. If authentication is required, it should use the global authentication parameter. If global authentication is not configured, it will use the interface authentication key. But since the packet is destined for remote loopback, it ends up failing authentication.
Remove the interface authentication or configuring the same global authentication key on both peers. In the following example, global authentication is configured and the RSVP session remained stable.
router-A# set protocols rsvp authentication-key <authentication-key>
Refer to the following document for guidance on how to enable the rsvp authentication globally, such as at the “ edit protocol rsvp ” hierarchy level:
edit protocol rsvp
"Authentication key (password): Neighboring routers use the password to verify the authenticity of packets sent from this interface or peer interface. To authenticate node hellos or remote messages between the Point of Local Repair (PLR) to the Merge Point (MP), enable authentication-key at the [edit protocols rsvp] hierarchy level."