MX68 - 84 QoS

[znaqvi786]

My customer is moving to WebEx calling from thier On-Premises call manager and some of the branches has Meraki MX, the question is if MX68/84 can do QoS for voice leveraging broadband and if there is any specific software version required on them.

[GIdenJoe]

All MX appliances have traffic shaping capabilities.
If you are fully tunneling to a DC MX then you can have two way QoS but if your transport for your voice call manager is the internet then you will only get outbound QoS.

On the security & SD-WAN -> traffic shaping page you can set these options.

Step1: Make sure your upstream and downstream bandwidth is set to the correct maximum values as your circuit speeds.

Step2: Make sure you match your voice traffic either through L7 application matching or through L3/4 IPs and ports.  And give it a DSCP value of EF(expedite forwarding).  You can set the queue to high but it should take the real-time queue by setting your DSCP value to EF.

Step3: Match some other traffic types and give them high/medium/low queuing service.

The logic is as follows.
- Each WAN interface on an MX has 4 queues
- The realtime queue is a strict priority queue (the moment 1 packet is waiting in that queue it gets serviced first)
- The other 3 queues are weighted bandwidth queues where high gets 4/7 of the maximum bandwidth, medium gets 2/7 and low gets 1/7.

So imagine you have a circuit with 70 Mbps upstream:
High would get 40 Mbps, medium 20 Mbps, low 10 Mbps.  However if one packet enters the realtime queues the other queues stops servicing and the realtime queue is emptied first.

[ww]

For 18.2  

• Firmware 18.2 and above: Class Based Weighted Fair Queueing with Deficit Round Robin is enforced on token bucket allocations. Allocation ratios are as follows:

  • Realtime: 8

  • High: 4

  • Medium: 2

  • Low: 1

[znaqvi786]

Thanks, Any specific software version required for this?

[CptnCrnch]

Nope 😎

[GIdenJoe]

Nope, as I already outlined.  In dashboard go to your network where you have the MX and in the menu select Security & SD-WAN -> Traffic Shaping.

All settings are available on that one page.