EVPN-Specific BMP RIB Statistics Extensions

Introduction RFC 7854 defined different BMP statistics message types to observe events on the router. The statistics are defined as counters or gauges to provide insights into BGP processing. This document extends the BMP RIB statistics defined in by adding EVPN-specific statistics types to monitor EVPN-related events in RIB-In and RIB-Out for the EVPN address family (AFI=25, SAFI=70). These EVPN-specific statistics provide enhanced visibility into multihoming, IP aliasing, dynamic inter-VRF route leaking (IVRL), route-map applications, and route-type specific counters, among others. The statistics defined herein are gauges (64-bit unsigned integers) unless otherwise specified, following the conventions in . They apply specifically to to the EV bombing in the EVPN SAFI and extend the per-AFI/SAFI structure where applicable.

Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 when, and only when, they appear in all capitals, as shown here.

EVPN BMP Statistics Extensions This section defines EVPN-specific statistics types for BMP. These statistics are applicable to the EVPN address family (AFI=25, SAFI=70) and extend the RIB statistics framework in . Each statistic is a 64-bit gauge unless noted otherwise, and the value can increase or decrease based on route processing events. The counters provide bits and bitmap to indicate Rib-In, Rib-Out and Pre, Post policy indicators if applicable.

Stat Type = TBD1: EVPN Route Type Statistics Consolidated counter for Standard EVPN route types (Type-1 to Type-8) across RIB-In and RIB-Out, Pre-policy and Post-policy stages. Extends BMP RIB statistics defined in . This statistic is specific to AFI=25, SAFI=70 and includes breakdowns for:

1st byte represents Type-1 to Type-8
2nd bit represent Rib-In or Rib-Out
3rd bit represent Pre or Post

Stat Type = TBD2: EVPN Locally Originated Routes Number of EVPN routes are only originated by the router and not relayed. It's helpful to keep a count of hosted EVI's (IMET for layer-2 EVIs) and Ethernet Segments (ESI and I-ESI) via Type-1 and Type-4). The first byte is used for indicating the route-type. As of today, standard route types for EVPN are numbered from 1 to 8

Stat Type = TBD3: EVPN Multihoming Ethernet Segments Number of Ethernet Segments (ESI) configured for multihoming. Based on and . The first two bit indicates if its a segment representing layer-2 multihoming or layer-3 multihoming or I-ESI.

Stat Type = TBD4: EVPN Multihomed EVIs Number of EVIs tied to an ESI or I-ESI. The first two bit indicate type of Ethernet Segment. The next 80 bits (10 bytes) can represent the ESI value.

Stat Type = TBD5: EVPN Aliased Paths Count per EVI Number of Aliased path per-EVI. First 4 bytes represent the EVI.

Stat Type = TBD6: EVPN Dynamic IVRL Number of EVPN routes leaked across VRFs due to matching route-targets. Related to RIB-In Post-policy (Type 2) as defined in . The first bit makes a distinction if the leak is indicated by MAC-VRF or layer-3, routing VRF. TBD: if need be, each counter can be indexed with Combination of source VRF and destination VRF.

Stat Type = TBD7: EVPN Route-Map, Policy Applicability Count Bitmap indicating which route attributes were modified by route-map (e.g., local-preference, AS-path, MED, community). The 2-byte bitmap includes flags for following attributes and many more, TBD. The exact bitmap for each category can be assigned later:

Local Preference
AS Path
MED
Community
Extended Community
Prefix List
MAC address list
Next Hop
EVI
Vendor specific Range

This statistic provides visibility into route-map modifications applied to EVPN routes on a per-attribute basis.

IANA Considerations IANA is requested to assign the following new parameters to the "BMP Statistics Type" registry:

Type = TBD1: EVPN Route Type Statistics
Type = TBD2: EVPN Locally Originated Routes
Type = TBD3: EVPN Multihoming Ethernet Segments
Type = TBD4: EVPN Multihomed EVIs
Type = TBD5: EVPN Aliased Paths Count per EVI
Type = TBD6: EVPN Dynamic IVRL
Type = TBD9: EVPN Route-Map, Policy Applicability Count

Security Considerations The EVPN-specific statistics defined in this document do not introduce any new security considerations beyond those already specified in for BMP and in for RIB statistics. BMP sessions should be protected using mechanisms such as TCP-AO or TLS to prevent unauthorized access to monitoring data.

Acknowledgements