MacOS Content Caching : Primary and Peered Configuration

In this scenario we have some Mac Mini devices setup with the Apple Content Caching mode enabled which means we need to enable the following option in the sharing settings: 

Then as we are only interested about "shared updates" which including System Updates for iOS/MacOS and applications, not personal data like iCloud and Music from iTunes we need to set this options as below:

Peered Policy

I will be using Priority policy would be most appropriate as in this example we need to ensure consistent pulling from your primary server and not other servers, so we will have the HQ Mac Mini Caching Server as Primary and all the other Mac Caching servers as:

Parent IP : Mac HQ Address
Policy : Priority

You can review all the policy's at the bottom of this article.

Setup the Mac Mini's

The the next setting to update is the primary server that the other peers will talk to, it makes sense to have this in a very client dense environment, then from that device

1. System Settings > Sharing > Content Caching
2. Enable Content Caching
3. Set "Cache:" to "Only Shared Content"

Then we need to setup the peered servers

1. System Settings > Sharing > Content Caching
2. Enable Content Caching
3. Under "Parents" add primary server's IP
4. Set Policy to "Priority" (this ensures consistent pulling from primary)

Then we need to verify Configuration:

sudo AssetCacheManagerUtil status

Then finally we need to verify this with a test connection:

sudo AssetCacheManagerUtil peerTest

Content Cache Parent Policy Options 

Default: Server automatically selects the most efficient parent based on response times and availability.
Round Robin: Distributes requests sequentially among parent servers, ensuring even load distribution.
Random: Randomly selects a parent server for each request, providing basic load balancing.
Sticky First: Uses the first responding parent server consistently unless it becomes unavailable.
Sticky Random: Randomly selects a parent server initially, then sticks with it until unavailable.
Priority: Always tries the first parent server in the list before falling back to others, ideal for primary/secondary hierarchies.

Before: Operational Diagram

This is what the topology looks like when you have all the MacOS devices working independently from one another, they all use the same internet feed which can cause excessive network traffic.

After: Operational Diagram

When this primary and peer has been implemented then all the peered MacOS device will talk to the Primary device which will then talk to the Internet, this also means as the Primary is in a dense location this will get all the updates that the others will then "pull" from the primary.