sFlow.org Peter Phaal http://www.sFlow.org/ InMon Corp. info@sflow.org Anoop Ghanwani Dell September 2012 sFlow LAG Counters Structure Copyright Notice Copyright (C) sFlow.org (2012). All Rights Reserved. Abstract This memo describes an sFlow version 5 structure for exporting Link Aggregation (LAG) counters. Table of Contents 1. Overview ...................................................... 1 2. sFlow Datagram Extension ...................................... 1 3. References .................................................... 3 4. Author's Addresses ............................................ 3 1. Overview This document describes additional structures that allow an sFlow agent to export information relating to IEEE 802.1AX Link Aggregation Control Protocol (LACP) [1]. sFlow version 5 is an extensible protocol that allows the addition of new data structures without impacting existing collectors. This document does not change the sFlow version 5 protocol [2], it simply defines an additional, optional, data structure that a network device can use to report LAG metrics. 2. sFlow Datagram Extension An sFlow agent exporting a counter_sample for a port that is part of a LAG must include an if_counters structure and a lag_port_stats structure. The lag_port_stats structure combines values from the dot3adAggPortTable and dot3adAggPortStatsTable. Both tables share FINAL sFlow.org [Page 1] FINAL sFlow LAG Counters Structure September 2012 dot3adAggPortIndex as the key and the values included in the lag_port_stats structure must correspond to the ifIndex reported in the if_counters structure. In order to ensure consistent results, all members of a LAG group must be represented by ifIndex Data Sources and share sFlow polling and sampling rate settings. In addition, an ifIndex Data Source associated with the parent Aggregation Port should also be present. All data sources associated with the LAG must support Counter Sampling (including the Aggregation Port - if present). Packet Flow Sampling should be implemented for each LAG member Data Source and the ingress/egress ifIndex numbers reported in Packet Flow Records should indicate individual LAG members. In this case, the Data Source associated with the parent Aggregation Port must only export Counter Records and does not perform Packet Flow Sampling. Alternatively, if it is not possible to perform packet sampling at the LAG member level, the Data Source associated with the Aggregation port must implement Packet Flow Sampling. In order to ensure consistent configuration across the LAG group, the sFlow MIB sFlowFsTable and sFlowCpTable tables must include the Data Source associated with the parent Aggregator Port and exclude the individual LAG members. Similar constraints must be enforced if configuration changes are made through an alternative configuration mechanism such as the command line interface. /* LAG Port Statistics - see IEEE8023-LAG-MIB */ /* opaque = counter_data; enterprise = 0; format = 7 */ struct lag_port_stats { mac dot3adAggPortActorSystemID; mac dot3adAggPortPartnerOperSystemID; unsigned int dot3adAggPortAttachedAggID; opaque dot3adAggPortState[4]; /* Bytes are assigned in following order: byte 0, value dot3adAggPortActorAdminState byte 1, value dot3adAggPortActorOperState byte 2, value dot3adAggPortPartnerAdminState byte 3, value dot3adAggPortPartnerOperState */ unsigned int dot3adAggPortStatsLACPDUsRx; unsigned int dot3adAggPortStatsMarkerPDUsRx; unsigned int dot3adAggPortStatsMarkerResponsePDUsRx; unsigned int dot3adAggPortStatsUnknownRx; unsigned int dot3adAggPortStatsIllegalRx; unsigned int dot3adAggPortStatsLACPDUsTx; FINAL sFlow.org [Page 2] FINAL sFlow LAG Counters Structure September 2012 unsigned int dot3adAggPortStatsMarkerPDUsTx; unsigned int dot3adAggPortStatsMarkerResponsePDUsTx; } 3. References [1] "IEEE Std 802.1AX-2008 IEEE Standard for Local and Metropolitan Area Networks - Link Aggregation", September 2008 [2] Phaal, P. and Lavine, M., "sFlow Version 5", http://www.sflow.org/sflow_version_5.txt, July 2006 4. Author's Address Peter Phaal InMon Corp. 580 California Street, 5th Floor San Francisco, CA 94104 Phone: (415) 283-3263 EMail: peter.phaal@inmon.com Anoop Ghanwani Dell 350 Holger Way San Jose, CA 95134 Phone: (408) 571-3228 EMail: anoop@alumni.duke.edu FINAL sFlow.org [Page 3]