As the current docs stand, it’s difficult to understand how to use/configure MeshNetworks in IstioOperator for any type of installation, especially Multi-Cluster and VMs.
Do we have documentation that goes into more detail on how to use MeshNetworks.
What I would like to have answered is:
1. When must we specify MeshNetworks?
-> The reason for this question is that we can see in
Install Multi-Primary on different networks that to set up two clusters we don’t need to specify the networks in the clusters at all.
Which is the opposite of what you’d expect according to the MeshNetworks description:
MeshNetworks (config map) provides information about the set of networks inside a mesh and how to route to endpoints in each network.
Assumption: Can we skip specifying networks when we label the namespaces with
2. What’s the benefit of specifying NetworkEndpoints (of the MeshNetworks.Network) explicitly?
Assumption: That’s how the control plane decides how to configure workloads located in different networks.
Assumptions about the properties:
- fromCidr: statically define workloads that are within a network. (i.e. 10.10.0.0/16 means that a workload with the IP 10.10.0.122 is considered to be in this network when created anywhere in the mesh)
- fromRegistry: dynamically interrogate the registry to define in which network a workload is.
If the above assumptions are correct, it means that this is actually important only during workload bootstrapping. Is that correct?
3. What’s the purpose of the section in the IstioNetworkGateway (of the MeshNetworks.Network)?
Assumption: This is how Control Plane knows how to configure workloads in other networks how to reach services within it.
Are any of my assumptions correct? Are there docs that can help me dig the details of this?