Replace PCE Nodes or Uninstall Cluster

This section describes how to add a new node to take the place of one that has failed. It also describes how to uninstall the PCE.

You can replace only one PCE node at a time.

Determine which node is the cluster leader:

sudo -u ilo-pce illumio-pce-ctl cluster-leader

On the cluster leader node, remove the failed node:
```
sudo -u ilo-pce illumio-pce-ctl cluster-leave ip_address
```
Where ip_address is the IP address of the failed node.
Before adding the new replacement node, ensure that:
- The new node has a valid runtime_env.yml file configured.
- The PCE software is not running.
On any existing node in the cluster (not the new node you are about to add), run the following command. For ip_address, substitute the IP address of the new node.
```
sudo -u ilo-pce illumio-pce-ctl cluster-nodes allow ip_address
```
On the new node, run the following command to add the new node to the cluster:
```
sudo -u ilo-pce illumio-pce-ctl cluster-join ip_address
```
Where ip_address is the IP address of any existing running node within the cluster.

After the new node successfully joins the PCE cluster, the PCE software is started.

Perform this procedure to take offline or replace a running node in the cluster; for example, when you need to upgrade the host hardware.

Performing these steps on a data node can result in the loss of your Illumination data and existing VEN Support Reports.

Stop the PCE software:
```
sudo -u ilo-pce illumio-pce-ctl stop
```
Stopping the PCE software causes PCE services to fail over to their backup node.
Wait for the node to enter the FAILED state. To check this status, run the following command on any other node:
```
sudo -u ilo-pce illumio-pce-ctl cluster-members
```
When you are removing the leader node, wait until the PCE has promoted another node to the leader before proceeding. Run the following command to determine the new leader node:
```
sudo -u ilo-pce illumio-pce-ctl cluster-leader
```

On the leader node, remove the failed node:

sudo -u ilo-pce illumio-pce-ctl cluster-leave ip_address

Before adding the new replacement node, ensure that:
- The node has a valid runtime_env.yml file configured.
- The PCE system software is not running.
On any existing node in the cluster (not the new node you are about to add), run the following command. For ip_address, substitute the IP address of the new node.
```
sudo -u ilo-pce illumio-pce-ctl cluster-nodes allow ip_address
```
On the new node, run the following command to add the new node to the cluster:
```
sudo -u ilo-pce illumio-pce-ctl cluster-join ip_address
```
Where ip_address is the IP address of any existing running node within the cluster.

After the new node successfully joins the PCE cluster, the PCE software is started.

To completely uninstall and remove the PCE for your system, perform the following steps:

Manually delete these directories:

/var/lib/illumio-pce
/var/log/illumio-pce
/etc/illumio-pce

Illumio Core 24.5 Administration Guide