Actions to Take When Server IP Address Changes

When Apinizer server IP address changes, update Kubernetes Master and MongoDB configurations, regenerate certificates, and update replica set configuration.

Actions for Kubernetes Master:

The following files need IP addresses changed:

/etc/kubernetes/admin.conf
/etc/kubernetes/controller-manager.conf 
/etc/kubernetes/kubelet.conf
/etc/kubernetes/scheduler.conf
/etc/kubernetes/manifests/etcd.yaml
/etc/kubernetes/manifests/kube-apiserver.yaml

Existing certificates are deleted:

cd /etc/kubernetes/pki
rm -rf apiserver.* apiserver-kubelet-client.*

New certificates are created (this stage may produce errors but they can be ignored):

sudo kubeadm init phase certs apiserver-kubelet-client
sudo kubeadm init phase certs apiserver

sudo systemctl restart kubelet

The current config file is moved to the user’s home directory for access:

sudo cp -i /etc/kubernetes/admin.conf $HOME/.kube/config
sudo chown $(id -u):$(id -g) $HOME/.kube/config

Actions for MongoDB:

Connect to MongoDB:

mongosh mongodb://<YOUR_NEW_MONGO_IP_ADDRESS>:25080 --authenticationDatabase "admin" -u "apinizer" -p

New IP settings are applied with the “force” option:

cfg = rs.conf()
cfg.members[0].host = "<YOUR_NEW_MONGO_IP_ADDRESS>:25080"
rs.reconfig(cfg, {force:true})