Adding a worker node (IBM Cloud Pak for AIOps on Linux)

Learn how to add a worker node to a Linux cluster that has a deployment of IBM Cloud Pak for AIOps running on it.

Procedure

Set environment variables.
1. Set default values for environment variables that might not exist in aiops_var.sh on upgraded deployments of IBM Cloud Pak for AIOps.
  
  Edit the shell script aiops_var.sh that you created when you installed IBM Cloud Pak for AIOps on your Linux cluster. Verify that you have the following environment variables set: HTTP_PROXY, , HTTPS_PROXY, NO_PROXY.
  If any are not defined, then set them to an empty string, as in the following example:
```
export HTTP_PROXY=""
export HTTPS_PROXY=""
export NO_PROXY=""
```
  For more information about aiops_var.sh, see Create environment variables in Online installation of IBM Cloud Pak for AIOps on Linux or Offline installation of IBM Cloud Pak for AIOps on Linux.
2. Run the following command to source the shell script aiops_var.sh that you created when you installed IBM Cloud Pak for AIOps on your Linux cluster.
```
. ./aiops_var.sh
```
3. Set an environment variable for the new worker node that you want to add.
```
export NEW_WORKER_NODE="<new_worker_node>"
```
  Where <new_worker_node> is the FQDN or IP address of the worker node to be added, for example agent8.acme.com.

Configure a new worker node.

Run the following commands to configure your new worker node.

For online deployments:

K3S_TOKEN=$(ssh ${TARGET_USER}@${CONTROL_PLANE_NODE} aiopsctl cluster node info --token-only)
K3S_HOST="https://${LOAD_BALANCER_HOST}:6443"

ssh ${TARGET_USER}@${CONTROL_PLANE_NODE} ssh ${TARGET_USER}@${NEW_WORKER_NODE} curl -LO "${AIOPSCTL_INSTALL_URL}"
ssh ${TARGET_USER}@${CONTROL_PLANE_NODE} ssh ${TARGET_USER}@${NEW_WORKER_NODE} tar xvf "${AIOPSCTL_TAR}"
ssh ${TARGET_USER}@${CONTROL_PLANE_NODE} ssh ${TARGET_USER}@${NEW_WORKER_NODE} mv aiopsctl /usr/local/bin/aiopsctl

HTTP_PROXY_FLAG=$(if [ -n "${HTTP_PROXY}" ]; then echo "--http-proxy=${HTTP_PROXY} "; fi)
HTTPS_PROXY_FLAG=$(if [ -n "${HTTPS_PROXY}" ]; then echo "--https-proxy=${HTTPS_PROXY} "; fi)
NO_PROXY_FLAG=$(if [ -n "${NO_PROXY}" ]; then echo "--no-proxy=${NO_PROXY} "; fi)

ssh ${TARGET_USER}@${CONTROL_PLANE_NODE} ssh ${TARGET_USER}@${NEW_WORKER_NODE} aiopsctl cluster node up --accept-license=${ACCEPT_LICENSE} --role=worker --server-url="${K3S_HOST}" --token="${K3S_TOKEN}" --registry-token="${IBM_ENTITLEMENT_KEY}" --app-storage="${APP_STORAGE_PATH}" ${HTTP_PROXY_FLAG}${HTTPS_PROXY_FLAG}${NO_PROXY_FLAG}

For offline deployments:

K3S_TOKEN=$(ssh ${TARGET_USER}@${CONTROL_PLANE_NODE} aiopsctl cluster node info --token-only)
K3S_HOST="https://${LOAD_BALANCER_HOST}:6443"

ssh ${TARGET_USER}@${CONTROL_PLANE_NODE} scp -r ~/.aiopsctl ${TARGET_USER}@${NEW_WORKER_NODE}:~/.aiopsctl/
ssh ${TARGET_USER}@${CONTROL_PLANE_NODE} scp /usr/local/bin/aiopsctl ${TARGET_USER}@${NEW_WORKER_NODE}:/usr/local/bin/aiopsctl

HTTP_PROXY_FLAG=$(if [ -n "${HTTP_PROXY}" ]; then echo "--http-proxy=${HTTP_PROXY} "; fi)
HTTPS_PROXY_FLAG=$(if [ -n "${HTTPS_PROXY}" ]; then echo "--https-proxy=${HTTPS_PROXY} "; fi)
NO_PROXY_FLAG=$(if [ -n "${NO_PROXY}" ]; then echo "--no-proxy=${NO_PROXY} "; fi)

ssh ${TARGET_USER}@${CONTROL_PLANE_NODE} ssh ${TARGET_USER}@${NEW_WORKER_NODE} aiopsctl cluster node up --accept-license=${ACCEPT_LICENSE} --role=worker --server-url="${K3S_HOST}" --token="${K3S_TOKEN}" --registry="${TARGET_REGISTRY}" --registry-user="${TARGET_REGISTRY_USER}" --registry-token="${TARGET_REGISTRY_PASSWORD}" --app-storage="${APP_STORAGE_PATH}" ${HTTP_PROXY_FLAG}${HTTPS_PROXY_FLAG}${NO_PROXY_FLAG} --offline --insecure-skip-tls-verify="${SKIP_TLS}"

Update the environment variables script aiops_var.sh.

When your worker node is succesfully added and configured, add an entry for it to the WORKER_NODES array for the new control plane node. This is to maintain the accuracy of the environment variables file.