HOW to do SPAN of Vlans (with utilization reaching more than Gigabit) and sending the sniffed data to a Gigabit port.

[elsaonita]

Hi!

We want to sniff a VLAN during peak hours, but we noticed that during that time, our equipment's (Cisco 7613 Router) CPU utilization reaches 28%(maximum). Is sniffing will increase the utilization of the router? We also want to know the threshold of the CPU Utilization for this device.

Thanks!

[Giuseppe Larosa]

Hello Elsa,

what I have seen in the past is that if you try to mirror 2 or 3 Gbps of traffic over a GE destination port supervisor cpu can even reach 100% after some time so I would recommend to avoid this, if the level of expected traffic is much higher then 1 Gbps.

Our findings were with Sup720 3BXL and 12.2(18)SXF9 and later with 12.2(33)SXI2a.

Hope to help

Giuseppe

[elsaonita]

Hi Giuseppe!

Thank you for your prompt response, So if a vlan has say, 4GPbps traffic, how can you send all those traffic to a SPAN destination port for analysis.
ANd do you have a supporting document from cisco for this? So that we have our reference.. Thanks!

Thanks!