Wired Intelligent Edge

Hi,

I have 1 HP2910al-24G and 4 HP 2620's and I have the need to run QoS due to the Voice traffic on the network. All the 2620's uplink to the 2910. 

I know there are a lot of QoS options but it's quite confusing. We have hard phones that connect to the switch (and the PC's connect to the phones). The phones tag Voice traffic into VLAN10. 

So based on this, I setup VLAN 10 on all the switches and made it the Voice VLAN. Below is an excerpt from one of the 2620's. 

I have a couple of questions. 

1) If I set a VLAN to VOICE, I don't need to use any of the QoS options like dscp do I? Something tells me I don't need this but I can't seem to find much in the docs either way. 

2) For the 2620's all ports should be UNTAGGED into Vlan1 and Tagged into VLAN10 correct? 

I don't think I need any QoS settings if I use the VOICE vlan option yes? 

Any insight would be most appreciated. 

Thank you,

-Steve

qos dscp-map 100110 priority 7

vlan 1
name "DEFAULT_VLAN"
untagged 1-52
ip address 10.42.42.16 255.255.255.0
exit

vlan 10
name "Voice"
qos dscp 100110
tagged 1-52
voice
no ip address
exit

Hi Steve,

I've never found any documentation on this, but my local SE told me a few years back that adding the voice keyword to a VLAN does the following:

• enables LLDP-MED
• sets 802.1p to 6
• sets DSCP to EF, and
• transmits the Vlan ID to the end device.

That seems to indicate that you're right and that no QoS settings are necessary.

Hi Paul,

I tried the same in my lab switch and found the following:

1)When I config the vlan with voice, the output of "show qos vlan-priority"  shows "No-override" for Apply rule as well as Priority.

2)When I configure the the "qos priority <0-7>" in the vlan context, the output of "show qos vlan-priority"  shows "Priority" for Apply rule and under priority it shows "7".

Firmware:  WC.16.04.10 and W.14.49 for the 2910 switch

Switch: 2930F and 2910 (tested on both)

As per this lab test, the qos command has to be explicitly configured in the vlan apart from the voice command.

Hi

1) If I set a VLAN to VOICE, I don't need to use any of the QoS options like dscp do I? Something tells me I don't need this but I can't seem to find much in the docs either way. 

Generally you’re right, but you can add this command to voice VLAN, "qos priority 5", just in case..

There is a lot of tweaking that you can do to improve voice traffic, it’s not necessary QOS commands on voice Vlan, it could be QOS command for entire network, but i think let the voice traffic to "run" for couple of weeks and if the clients having some problems with the voice then you can make some steps to improve it.

2) For the 2620's all ports should be UNTAGGED into Vlan1 and Tagged into VLAN10 correct? 

yes.

good luck :)

Thanks everyone for the input. 

Apparently I can only flag one response as a Solution. I wish I could flag a second one. 

> I can only flag one response as a Solution. I wish I could flag a second one.

Right.  But you can assign Kudos to each post that helps you.

The only other question I have is now that I have VLAN10 as the Voice VLAN, how can I see that Voice traffic is actually prioritized? 

Are there any commands I can run to see that this is actually working? 

Thanks again,

-Steve

I would really like to know if there is anyway to tell if setting the Voice VLAN actually is working. 

I ask because I can't seem to find any commands that show me this is working.

NY-HP2620-2# show qos vlan-priority

VLAN priorities

VLAN ID Apply rule | DSCP Priority
------- ----------- + ------ -----------
1 No-override | No-override
10 No-override | No-override

NY-HP2620-2#

Is there anyway to tell that the Voice VLAN is actually prioritized? 

Hi

i'm, meirhasin from the top of the thread, i just opened new account to get new name :)

about qos utilization, try to goolge this command:

sh qos resources

Thanks. 

What's interesting about 'show qos resources' is that you get different responses on a 2910 vs a 2620.

On a 2910 it does shomw some stats but they're all '0' and then at the bottom it clearly states this command does not report on VLAN priority: 

"Resource usage includes resources actually in use, or reserved for future
use by the listed feature. Internal dedicated-purpose resources, such as
port bandwidth limits or VLAN QoS priority, are not included." 

On a 2620 I see something completely different although it makes no sense whatsoever. 

show qos resources

Policy Engine Resource Usage
Rules Rules Group
Group Allocated Used Number
------------------------+------------+------------+------------+
QoS | 0 | 0 | 1 |
rate-limit/misc | 128 | 2 | 2 |
CLI-ACL | 0 | 0 | 3 |
IDM-ACL | 0 | 0 | 4 |
Free | 1920 |

QoS Group Usage Detail
Rules Group
Type Used Number
-------------------------------------+------------+------------+
internal (double tag drop) | 2 | 2 |

So I am not sure this is giving me what I want to see. 

I've found that the easiest way to see if the QOS/DSCP priorities are being set correctly is to mirror one of the ports to a wireshark client and capture a trace of the target of interest (phone, in this case)  traffic.  examine the packets and you can find the QOS/DSCP fields to see if they're set as you expect.