Model(s): DCS-7280R, DCS-7280R2, DCS-7280E, DCS-7500R, DCS-7500R2, DCS-7500E, DCS-7050X, DCS-7060X, DCS-7250X, DCS-7260X, and DCS-7300X, DCS-7280R3, DCS-7280SR2A-48YC6, DCS-7280CR2-60, DCS-7280CR2A-60, DCS-7280CR2K-60, DCS-7280CR2-30, DCS-7280CR2A-30, DCS-7280SRAM-48C6, DCS-7280SR2K-48C6, DCS-7500R3, DCS-7500R2A-36CQ-LC, DCS-7500R2AK-36CQ-LC, DCS-7500R2AM-36CQ-LC, DCS-7500R2AK-48YCQ-LC. and DCS-7800R3
Version(s): EOS 4.29.2F
URL: https://www.arista.com/en/um-eos/eos-sflow
Notes: sFlow processing is done in software unless a hardware-accelerated supported switch is configured for hardware acceleration. See the section “Hardware Accelerated sFlow” at the end of this document.
Configuration Steps
Set the sFlow collector IP Address along with a destination port (Arista uses 6343 as the default port). The IP address set here is the Scrutinizer collector IP address.
switch(config)#sflow destination 10.2.13.2 2055 switch(config)#
Alternatively, the sflow source-interface command can be used. The IP address configured on the specified interface will be used as the source address of the sFlow datagrams
switch(config)# sflow source-interface vlan 25 switch(config)#
Set the sflow polling-interval to send counter data to the sFlow collector. Plixer recommends using a 10-second polling interval.
switch(config)# sflow polling-interval 10 switch(config)#
Set the sampling rate using the sflow sample Packets are sampled at random intervals to avoid inaccurate sampling of periodic events. A rate of 16384 corresponds to an average sample of one per 16384 packets. The default rate is 1048576.
switch(config)# sflow sample 65536 switch(config)#
Enable sFlow globally on the switch.
switch(config)# sflow run switch(config)#
Hardware Accelerated sFlow
With hardware acceleration, all sFlow processing is done in hardware using specialized chips, called accelerators. These accelerators process sampled packets and send out sFlow datagrams similarly as the software agent. Involvement from the CPU is very little and the chips are dedicated to sFlow, performance is higher and the CPU has more availability for other tasks, even with high sampling rates.
The Hardware accelerated sFlow is supported on the following switch series:
DCS-7280R3, DCS-7280SR2A-48YC6, DCS-7280CR2-60, DCS-7280CR2A-60, DCS-7280CR2K-60, DCS-7280CR2-30, DCS-7280CR2A-30, DCS-7280SRAM-48C6, DCS-7280SR2K-48C6, DCS-7500R3, DCS-7500R2A-36CQ-LC, DCS-7500R2AK-36CQ-LC, DCS-7500R2AM-36CQ-LC, DCS-7500R2AK-48YCQ-LC. and DCS-7800R3
However, the following switches have a limitation:
DCS-7280R, DCS-7280R2, DCS-7280E, DCS-7500R, DCS-7500R2, and DCS-7500E.
Before enabling hardware-accelerated sFlow, the following requirements must be fulfilled:
- sFlow must be running globally.
- Routing must be enabled in any VRF. This is required for sFlow datagrams to be routed to the collector(s).
To enable hardware-accelerated sFlow use the following command sflow hardware acceleration.
switch(config)# sflow hardware acceleration switch(config)#