Using QoS Traffic Shaping on the HP 3100 V2 Network Switch

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1 Technical white paper Using QoS Traffic Shaping on the HP 3100 V2 Network Switch Table of contents Traffic Shaping on the HP 3100 V Test Environment... 2 Initial Testing... 3 Test Results... 3 Appendix A Configuration Settings on the test HP 3100 V AA3-xxxxENW, Month 20XX Click here to verify the latest version of this document

2 Traffic Shaping on the HP 3100 V2 HP has introduced a second version of the HP 3100 switch that is known as the V2 switch. The major differences between the HP 3100 original and the HP 3100 V2 is that you now have support for QoS Traffic Shaping, IPV6, LLDP-MED, 802.3ah, and DHCP V6 Client. One of the major architecture differences in the HP 3100, either version, is that there are only 4 hardware input/output queues for traffic shaping instead of the 8 hardware input/output queues on the more featured and higher end switches that HP sells. As a result, you have the ability by using the qos map-table commands to modify the Dot1p and DSCP mappings to the input/output queues. This paper describes customer scenario in which the customer wanted to have 4 streams defined, with traffic shaping to 10Mb each, so that the output would be approximately 40Mb in order to comply with the contractural agreement that they had with their ISP. Any traffic outside of those performance parameters would be dropped by the ISP so it was critical that the HP 3100 V2 switch be configured to send traffic at the desired rate. Test Environment For the sake of this testing, they defined 4 streams in the Smartbits Test Center traffic generator: 1. RT Real-time IP filtered traffic between two IP addresses 2. D1 A UDP stream between two specific IP addresses and UDP ports 3. D2 A TCP stream between two specific IP addresses and TCP ports 4. D3 Another TCP stream between two specific IP addresses and a different set of TCP ports The streams were equally divided on the Smartbits Test Center to 25mb per stream into the HP 3100 V2 to fill the Fast Ethernet input connection. The output from the HP 3100 V2 was rate limited with traffic shaping to be 10mb/stream, on output, to another Fast Ethernet port. The following table lists the streams and their settings for Dot1p, DSCP, and QoS to achieve the desired result: Stream Dot1p QoS DSCP Decimal DSCP Hex RT 6 C8 CS D1 4 A0 CS D AF D AF11-10 A0 Table 1 Desired stream settings for Dot1p, DSCP, and QoS The following table shows how the DSCP to Dot1p mappings in 8 Output Queue and 4 Output Queue switches are made: DSCP Range Dot1p Setting 4 Output Queue Switches & & 3 1

3 & & 7 3 Table 2 DSCP to Dot1p mappings There are 8 Dot1p settings available (numbered 0 7) in keeping with the Comware software running on more featured HP switches. The above table shows how the 8 Dot1p settings are mapped in 4 output queue switches. This testing was done with the default settings for the qos map-tables. If needed, this can be modified by using the qos map-table command. If you decide to modify the mappings, you must be aware of how the traffic will ultimately map to the output queues in order to get your desired performance result. On the basis of sending the right traffic to the right output queue, we found that in order to get the desired QoS Traffic Shaping of approximately 10mb output per stream, or 40mb output in the aggregate, we had to ensure that each stream made it to a unique output queue. As long as the traffic is either marked correctly on inbound, or remarked in the traffic behavior on the switch in accordance with Table 2 above, you will get the desired output rate. Initial Testing The initial testing was done with the stock code on the switch, R5103P01. In that release, if you removed the qos trust setting from the switch configuration the default was something called port priority. That meant that all the traffic coming in on a port would receive the same priority. The result of that was about 10mb output total for the switch because all of the traffic would be going through a single output queue.. In the newer R5202 code for the HP 3100 V2, there was a bug relating to when a qos behavior has both Dot1p and local-precedence remark statements. Prior to R5202, the local-precedence remark statement was ignored or not used and the switch ended up using the port priority defined in the interface. If no port priority is defined in the interface, the default is 0. In release R5202 and later the local-precedence remark statement now works. Setting up Local Precedence In order to set up local precedence, you set up a series of ACL s to describe the traffic that you want to give special treatment to. This is achieved by using the traffic classifier command. The traffic classifier classifies the traffic according to an acl. The traffic behavior allows you to act on the traffic that was classified. The traffic behavior command allows several actions such as: re-mark the traffic with values for Dot1p, DSCP, and adjust the local precedence among other things. You can also enable to see how much traffic is triggering a particular traffic behavior. The qos policy ties the traffic classifier and traffic behavior together. Once the defining configuration is in place, you modify the appropriate inbound interface to add the qos apply policy for inbound traffic. That will activate the qos settings on the interface. On the output side, you define the traffic shaping you need with the qos gts command. In our case, we specified treatment for each of the 4 output queues. Test Results With all of that in place, we were able to get the 10Mb output per stream or queue. That resulted in an aggregate output of 40Mb on the output interface as desired by the customer.

4 Setting up Port Priority, if desired If you still need the ability to queue traffic based on Port Priority, have no fear. It is still possible. There are two things that need to be done: 1. Remove any remark local-precedence statements from all traffic behaviors 2. Execute the undo qos trust command The lack of a remark for local-precedence, and the qos trust set to the default, will get you the port priority treatment that you need.

5 Appendix A Configuration Settings on the test HP 3100 V2 What follows are the relevant configuration sections of the working configuration on the HP 3100 V2 8-Port Switch running the latest R5202 code: version , Release 5202 acl number 3000 name RT rule 10 permit ip source destination acl number 3001 name D1 rule 10 permit udp source source-port eq 80 destination acl number 3002 name D2 rule 10 permit tcp source-port eq 95 destination-port eq 1025 acl number 3003 name D3 rule 10 permit tcp source-port eq 1024 destination-port eq 1025 traffic classifier RT operator and if-match acl name RT traffic classifier D2 operator and if-match acl name D2 traffic classifier D3 operator and if-match acl name D3 traffic classifier D1 operator and if-match acl name D1 traffic behavior RT remark dscp 50 remark dot1p 6 remark local-precedence 6 traffic behavior D2 remark dot1p 2 remark dscp af22 remark local-precedence 2 traffic behavior D3 remark dscp af11 remark dot1p 1 traffic behavior D1 remark dscp cs5 remark dot1p 4 remark local-precedence 4 qos policy FILTER1 classifier D1 behavior D1 classifier D2 behavior D2 classifier D3 behavior D3

6 classifier RT behavior RT interface Ethernet1/0/3 description INPUT port link-type trunk port trunk permit vlan 1 to to 4094 qos apply policy FILTER1 inbound interface Ethernet1/0/4 description OUTPUT port link-type trunk port trunk permit vlan 1 to to 4094 qos gts queue 3 cir cbs qos gts queue 0 cir cbs qos gts queue 1 cir cbs qos gts queue 2 cir cbs Please note that in the traffic behavior for stream D3 we did not specify a local precedence. Since all of the other streams were set with the local precedence, we decided to not set it for D3 so it would end up in the default local precedence of 0 which would put the D3 traffic in output queue 1, as desired. Each of the streams would now end up in their own output queue: Stream RT traffic is in output queue 3 Stream D1 traffic is in output queue 2 Stream D2 traffic is in output queue 0 Stream D3 traffic is in output queue 1 You will also notice that there is no qos trust command in the above configuration. That is because we are using the new qos trust default of Local Precedence in this version of the HP 3100 V2 code. With this configuration in place, you could choose any of the qos trust settings of the default, Dot1p, or DSCP and get the same desired result. Also, if you remove the remarks for local-precedence and undo qos trust, you will also be able to get the original default behavior of port priority.