inter vlan routing throughput between gigabit interfaces on a 3560.

[Fabio Francisco]

Hi Guys,

I'm facing a poor throughput on a Cisco Catalyst 3560 10/100/1000.

Running Iperf I managed to get an average of 300mbits/s on the same vlan and routing between vlans I get a roughly 140 mbits/s.

What's acceptable? Is there any command to check throughput performance on the switch itself?

Thanks in advance.

Fabio

[Latchum Naidu]

Hi Fabio,

There may not be any problem with your switch ports.
As I have faced the same problem, I would suggest you to check from server end, is that servers have enough good resources (processr, RAM and CPU may high).
You may connect other devices on the same port and check the throughput for confirmation.

If this answered your question please click on correct answer.
Regards,
Nadiu.

[Eugene Lau]

Hi Fabio,

Most of the 3560 range should be wire rate with the exception of the over subscribed models.

Example:

Table 8

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps7078/product_data_sheet0900aecd805bac22.html

This means you should be able to achieve 1G on a 1G interface. The 3560 is would also switch Layer3 traffic in hardware and the throughput rate should be the same whether it is SAME VLAN or INTER VLAN - performance may be affected by certain features such as ACL with Log keyword etc

Some questions:

a. Are you using the same server/client hardware in IPERF and simply changing the traffic from SAME VLAN to INTER-VLAN?

b. Are there any L3 features enabled? such as ACL's etc.

c. Does the CPU elevate when you do the INTER-VLAN test -> that only reaches 140MB/s?

d. Do the interface rates roughly match the IPERF numbers?

e. Are you running multiple streams or single stream?

f. UDP or TCP?

Typically, when using IPERF - 300MB/s may be the limit of the CPU of the server/client hardware you are using too

HTH

Eugene