Quick Reference Guide

1080 PowerConnect B-Series TI24X Configuration Guide
53-1002269-02
sFlow
A
• Identifies ingress and egress interfaces for the sampled flows
• Combines sFlow samples into UDP packets and forwards them to the sFlow collectors for
analysis
• Forwards byte and packet count data, or counter samples, to sFlow collectors
sFlow is described in RFC 3176, “InMon Corporation's sFlow: A Method for Monitoring Traffic in
Switched and Routed Networks”.
NOTE
When sFlow is enabled on a PowerConnect B-Series TI24X switch QoS will support 7 priority queues
rather than 8. This is because QoS queue 1 is reserved for sFlow and does not get used for other
types of traffic. Any non-sFlow packets assigned to QoS queue 1 will be redirected to QoS 0.
sFlow support for IPv6 packets
The Dell implementation of sFlow features support IPv6 packets. This support includes extended
router information and extended gateway information in the sampled packet. Note that sFlow
support for IPv6 packets exists only on devices running software that supports IPv6.
The configuration procedures for this feature are the same as for IPv4, except where the collector is
a link-local address on a Layer 3 switch. For details refer to “Specifying the collector” on
page 1082.
Extended router information
IPv6 sFlow sampled packets include the following extended router information:
• IP address of the next hop router
• Outgoing VLAN ID
• Source IP address prefix length
• Destination IP address prefix length
Note that in IPv6 devices, the prefix lengths of the source and destination IP addresses are
collected if BGP is configured and the route lookup is completed. In IPv4 devices, this information is
collected only if BGP is configured on the devices.
Extended gateway information
If BGP is enabled, extended gateway information is included in IPv6 sFlow sampled packets,
including the following BGP information about a packet destination route:
• The autonomous system (AS) number for the router
• The source IP AS of the route
• The source peer AS for the route
• The AS patch to the destination
NOTE
AS communities and local preferences are not included in the sampled packets.
To obtain extended gateway information, use “struct extended_gateway” as described in RFC 3176.