Traffic Shaping

[DaveG]

I am trying to figure out how to deploy traffic shaping for the below situation. I am receiving conflicting information, so I thought I would reach out to the group to see if anyone could provide some guidance.

I have 5 separate subnets in which I need to apply traffic shaping to. Each subnet shares a 300 down and 30 up internet connection.

Each subnet should have a minimum of 60 down and 6 up; however, if bandwidth is available, each subnet should be allowed to burst to 300 down and 30 up.

In conversations with support, it was recommended I create 5 separate "shared shaping" policies for each subnet. However, after researching this further and based on my understanding of the way policies are applied, each policy operates independently, so each policy would think it could burst to 300 as it is not aware of the other policies.

In other conversations with support, it was recommended I create a single "shared shaping" policy. Based on my understanding, this approach would not allow me to achieve a guaranteed bandwidth for each subnet. 

[Toshi_Esumi]

What the support is saying is right as long as you set "set per-policy disable" on the traffic-shapers. Then your "guaranteed-bandwith" for download 60Mbps/upload 6Mbps and "maximum-bandwidth" for download 300Mbps/upload 30Mbps would be shared with those 5 shaping-policies. Only if you set the per-policy enabled, it would work independently.

You need to have two shapers for download and upload, and set upload-shaper to initiating direction and download-shaper to the "reverse" direction.

It's explained here.

https://docs.fortinet.com/document/fortigate/6.2.10/cookbook/933502/shared-traffic-shaper

Toshi

[DaveG]

Thanks for the reply. I am still confused how a shared shaper with per-policy disabled will guarantee 60Mbps down and 6Mbps up for each individual subnet. If the shaper is shared across the 5 policies, I would expect the 5 subnets as a whole to be guaranteed 60Mbps down and 6Mbps up. I am sure I am missing something.

[Toshi_Esumi]

Ok, I guess I stated opposite. You need to "enable" per-policy on the shaper for individual subnet to have guaranteed bandwidth 60M/6M, and apply it to 5 different shaping-policies. Probably you don't want to set the maximum.

[DaveG]

That makes since. I thought about configuring it that way but I wasn't sure how the maximum bandwidth would work. I suspect the maximum bandwidth will simply be regulated by the ISP and the guaranteed bandwidth will be regulated by the shaping policy.

[Toshi_Esumi · Accepted solution]

The maximum-bandwidth would be more meaningful when it's used in a shaper with per-policy disabled, or shared shaper. So regardless how many shaping-policies are involved, the hard-limit of the total bandwidth for the traffic is something specific, like only up to 255Mbps/25Mbps for all traffic other than voice to leave 5M/5M for voice.

[DaveG]

Makes since, I really appreciate your help with this.