Is it possible to enable accelerated networking on a VMX-M concentrator within Azure

[Damien_Zwart]

Hello everybody,

I was wondering if someone has enabled accelerated networking on VMX concentrators in Azure.

The VM's are of this type;
Standard F4s v2 (4 vcpus, 8 GiB memory)
We have two concentrators in Azure, all traffic between spokes flows over the primary concentrator in Azure.
Recently I have lowered the MTU size on the Meraki AutoVPN to 1390.
Since then camera's and DECT stations started working without any problems. When I make packet captures on the tunnel interface of the primary concentrator I can see the size of the packets is ok, but I still see continuous retransmits. Because of this I was wondering if enabling accelerated networking would resolve this because of the advantages it could bring. I can't see anything about this in official documentation.

Thanks in advance,

Regards,

Damien Zwart

[Damien_Zwart]

and of cource I meanth enabling accelerated networking on the NIC connecting to the VMX

[alemabrahao]

Since there's nothing documented, I'd say it's not possible.

https://documentation.meraki.com/MX/Install_and_Get_Started/Installation_Guides/vMX_Setup_Guide_for_...

[Damien_Zwart]

Good morning, I posted this question also on another Meraki forum and someone replied ;

"I enabled 'Accelerated Networking' on two vMX Mediums this this past weekend and haven't had any production issues."

[Damien_Zwart]

I am thinking of trying it, because of the advantages it will bring;

Yes, accelerated networking can be enabled for Meraki vMX appliances in Azure, which improves performance by directing network traffic directly to the VM's virtual network interface (vNIC), bypassing the host's virtual switch. This is configured in the Azure portal by enabling accelerated networking on the virtual machine's network interface (NIC) during creation or for an existing VM. 

How to enable it

• During VM creation: When creating the virtual machine for the vMX, go to the "Networking" tab and ensure "Accelerated networking" is set to "Enabled".
• For an existing VM:
  1. Navigate to your virtual machine in the Azure portal.
  2. Select "Networking" from the left-hand menu.
  3. Click on the "Network Interface" link.
  4. Go to the "Accelerated networking" settings in the "NIC Overview" page.
  5. Select "Enabled" and save the changes. 

Benefits

• Reduced latency: By bypassing the virtual switch, the vMX can process packets more directly, leading to lower latency.
• Improved performance: Accelerated networking significantly improves networking efficiency, handling large numbers of simultaneous connections and enhancing performance for network-intensive workloads.
• Direct traffic forwarding: Traffic is forwarded directly to the VM by the NIC, which applies policies in hardware instead of through the host's software. 

[Damien_Zwart]

I checked wether the used VM image has support for accelerated networking with this scipt in Azure CLI:


az vm list-skus \
--location westeurope \
--all true \
--resource-type virtualMachines \
--query '[].{size:size, name:name, acceleratedNetworkingEnabled: capabilities[?name==`AcceleratedNetworkingEnabled`].value | [0]}' \
--output table


And the used VM SKU is listed, so that is another confirmation it should work without problems.

[Damien_Zwart]

e enabled acce;lerated networking today, without any problems

[Damien_Zwart]

https://imgs.ecsrv.com/design/cprod/103127/DesignImage_1051.pdf