Fixing TLS connection errors on VMs

To change the MTU value for all network interfaces created for Docker containers on the VM, modify the Docker service configuration. To do this, follow these steps:

1. Run the sudo nano /etc/docker/daemon.json command and add the following section to the file:

   {
   "mtu": 1450
   }
   

2. Save the file and run sudo systemctl restart docker to restart Docker.

To change the MTU value for the network interfaces of all VMs in the Managed Service for Kubernetes node group, you need to create a DaemonSet object and apply it to the cluster. To do this, follow these steps:

1. Create a file with the object manifest by running nano ds-set-mtu.yaml. Add the following content to the file:

   apiVersion: apps/v1
   kind: DaemonSet
   metadata:
   name: set-mtu
   spec:
   selector:
      matchLabels:
         app: set-mtu
   template:
      metadata:
         labels:
         app: set-mtu
      spec:
         containers:
         - name: set-mtu
         image: amouat/network-utils
         command: ["sh", "-c", "ip link set dev <interface_name> mtu 1450"]
         securityContext:
            privileged: true
         resources:
            requests:
               cpu: "100m"
               memory: "50Mi"
            limits:
               cpu: "200m"
               memory: "100Mi"
         hostNetwork: true
         nodeSelector:
         kubernetes.io/os: linux
   

2. Save the manifest file and run kubectl apply -f ds-set-mtu.yaml to apply it to the cluster.

To change the MTU value on the VM interface, run cmd as administrator and follow these steps:

1. Run the netsh interface ipv4 show subinterfaces command to display a list of all available network interfaces on the VM. In the Interface field, select and save the name of the network interface where you want to change the MTU value.

2. Run the netsh interface ipv4 set subinterface "<interface_name>" mtu=1450 store=persistent command, specifying the name of the network interface where you want to set the new MTU value. This value will persist after the system reboot.

3. Restart the VM.

4. Make sure the new MTU value persists on the network device by running netsh interface ipv4 show subinterfaces.