Basic Components of a Network

out-of-band management network
- this is used for lights-out ipmi/serial management of hosts
in-band management network
- Used for underlying infrastructure control via ssh and other management connections on devices like switches or virtualization host. Containers/VMs are then connected to bridges that are mapped to networks.
service networks
- This is used to serve up actual VM guests, containers and other devices on vlans outside of management networks for isolation and control. This would serve up https, sftp, sql and a host of other service oriented protocols. access-control-lists, such as a firewall, should be used to limit access to these services and outside access should be corralled and limited to specific port.
storage networks
- Just as the name implied this is used for attached storage purposes like SAN/NAS protocols such as iscsi, nfs, cifs and access should be restricted from services network.

refs