The BGP Monitoring Protocol (BMP) provides a monitoring station that obtains route updates and statistics from a BGP router. The BMP protocol is described in detail in RFC 7854, BGP Monitoring Protocol (BMP). A router communicates information about one or more BGP sessions to a BMP station. Specifically, BMP allows a BGP router to advertise the pre-policy or post-policy BGP RIB-In from specific BGP peers to a monitoring station. This allows the monitoring station to monitor the routing table size, identify issues, and monitor trends in the table size and update or withdraw the frequency. The BMP station is also sometimes called a BMP collector. A router sends information in BMP messages to a BMP station.
BMP is a unidirectional protocol. A BMP station never sends back any messages to a router.
BMP allows a router to report different types of information.
A router can send BMP messages with notifications when neighbors go into or out of the established mode (for example, when the peer goes up or down). These notifications are called BMP peer-up and peer-down messages.
A router can periodically send statistical information about one or more neighbors. This information consists of a number of counters, for example, the number of routes received from a particular neighbor or the number of rejected or accepted routes because of ingress policy parameters.
Other counters report the number of errors that were encountered, for example, AS-path loops, duplicate prefixes, or withdrawals received.
A router can also report the exact routes received from a particular neighbor. This action is called route monitoring. A router encapsulates a BGP route into the original BGP update message, then encapsulates that BGP update message in a BMP route monitoring message.
BMP on an SR OS router reports information about routes that were received from a neighbor. The SR OS cannot report routes that were sent to a neighbor.
When periodic statistics are enabled, the router sends all the statistics as described in RFC 7854, section 4.8, with the exception of statistic number 13, ‟Number of duplicate update messages received”. The supported statistics are listed in Table: Supported statistics .
| Statistic | Type |
|---|---|
Number of Prefixes rejected by inbound policy |
0 |
Number of duplicate prefix advertisements received |
1 |
Number of duplicate withdraws received |
2 |
Number of invalidated prefixes because of Cluster_List loop detection |
3 |
Number of invalidated prefixes because of AS_PATH loop detection |
4 |
Number of invalidated prefixes because of Originator ID validation |
5 |
Number of invalidated prefixes because AS-Confed loop detection |
6 |
Total number of routes in adj-rib-in (all families) |
7 |
Total number of routes in Local-RIB (all families)` |
8 |
Number of routes per address-family in adj-rib-in |
9 |
Number of routes per address-family in loc-rib |
10 |
Number of updates subjected to treat-as-withdraw |
11 |
Number of prefixes subjected to treat-as-withdraw |
12 |
The values in these counters are the same values that can be seen in the show>router>bgp>neighbor ip-address [detail] command in the CLI.