Some Layer 2 network deployments collect statistics on physical Ethernet ports and on Layer 2 interfaces at a high-frequency using a push model to, among others, monitor traffic, diagnose network issues, or provide billing. SR OS supports cflowd and XML accounting; however, those mechanisms are either Layer 3-specific, or focus on providing statistics at extremely large scale (therefore use a pull model and cannot support high-frequency counter updates). To meet the statistics collection requirements of such Layer 2 deployments, SR OS supports sFlow statistics export using sFlow version 5.
The following list gives the main restrictions for sFlow support:
sFlow data sources require multicore line cards (IOM), enabling sFlow on a card that is not a multi-core is not blocked and can be detected by SNMP trap/log generated by sFlow
To meet high-frequency export of counters, sFlow implementation is targeted for low per-port VLL/VPLS SAP scale only. The configuration is blocked if the per-port VLL/VPLS SAP limit exceeds sFlow limit. Contact your Nokia representative for per-platform scaling limits applicable.