Deploying 5G core network with Free5GC, Kubernetes and Helm

Happy devSecOps

(λx.x)eranga

Published in

Effectz.AI

4 min readDec 25, 2021

Background

In my previous post I have discussed about deploying 5G core network with Open5GS and configuring 5G UE & 5G RAN simulator with UERANSIM. In this post I’m gonna discuss about deploying Free5GC based 5G core network with Kubernetes and Helm. The monitoring of the services done with Prometheus/Grafana. All the deployments which related to this post available on gitlab. Please clone the repo and continue the post.

Free5GC

Free5GC is an open-source project for 5th generation (5G) mobile core networks. It is the first open-source 5G core network in the world to conform to the 3GPP Release 15 (R15) international standards. Free5GC’s original goal was to provide academics with a platform to test and prototype 5G systems. However, due to Free5GC’s completeness and open source code, it also has commercial value, especially for private 5G networks.

Free5GC-based 5G core network can be deployed with Kubernetes using Helm charts. Orange-OpenSource provides open source Helm charts to deploy Free5GC with Kubernetes. Following are the main steps to follow to deploy the Free5GC 5G network on Kubernetes.

Configure Kubernetes

I have run the single node Minikube Kubernetes cluster on AWS Ubuntu 20.04 server. To run Free5GC services I had to enable 4 CPUs, 8 GB Memory for Kubernetes cluster(otherwise prods may stop saying Insufficient cpu/memory).

For handle the networking in Kubernetes cluster I have used Calico container network interface(CNI) plugin. CNI supports plugin-based functionality to simplify networking in Kubernetes. By default Kubernetes using the Kubenet plugin to handle networking(e.g handling incoming/outgoing requests). Kubenet is a very basic plugin that doesn’t have many features. If we need more features like isolation between namespaces, IP filtering, traffic mirroring or changing load balancing algorithms then other network plugins should be used. There are various CNI plugins available, Flannel, Calico, WeaveNet, Cilium, Canal. In this scenario I have used Calico CNI plugin. With Calico I have assigned static IPs to pods, enable SCTP traffic on cluster etc.

Enable Multus-CNI Plugin

Multus-CNI is a CNI plugin for Kubernetes that enables attaching multiple network interfaces to pods. Typically, in Kubernetes each pod only has one network interface (apart from a loopback. With Multus you can create a multi-homed pod that has multiple interfaces. This is accomplished by Multus acting as a meta-plugin, a CNI plugin that can call multiple other CNI plugins.

To run Multus-CNI, first I need to install a Kubernetes CNI plugin to serve the pod-to-pod network, I have used Calico CNI plugin. The Calico CNI plugin creates the default network interface that every pod will be created with. Each network attachment created by Multus will be in addition to this default network interface.

Deploy Helm Chart

Once configured the K8s cluster and the CNI, I can deploy the Free5GC 5G core network services with Helm charts. I have used the Free5GC Helm chart provided by Orange-OpenSource.

Free5GC Web UI

Free5GC provides Web UI to configure the UE devices and other configurations in the 5G core network. The Web UI is exposed with a Kubernetes service with nodePort=30500. I can access it by using this url {replace-by-the-IP-of-one-of-your-cluster-nodes}:30500 or Kubernetes port forwarding. In the Web UI, I can register the UE device configurations. I have deployed the 5G core services on AWS. To access the Web UI service from my local machine I have done SSH port forwarding.

Then I can register a subscriber(UE device) via the Web UI. Read more information about UE device configuration in the Web UI from my previous post.

Service Monitoring

To monitor the 5G core services on Kubernetes I have used Prometheus. The visualization done with Grafana. prometheus-community provides Helm chart to install the Prometheus/Grafana services. Following are some services available on prometheus-community.