Step 2: Apply the Patch to Data Nodes

When applying a patch manually, apply the patch to nodes dedicated to storing and processing data prior to applying the patch on nodes that run the CLDB. This includes nodes that run the Fileserver for storage and processing components such as the NodeManager and the HBase client.

Note: For clusters with more than 100 data nodes, it is a best practice to apply the patch in batches. Also, wait a few minutes before proceeding to the next batch of nodes.

On each data node:

Stop the Warden and ZooKeeper (if installed) services:
1. To stop Warden, run the following command:
```
sudo service mapr-warden stop
```
2. If Zookeeper is installed on the node, run this command:
```
sudo service mapr-zookeeper stop
```
If there is already a patch installed on the cluster, run one of the following commands to uninstall it:
- On CentOS/Redhat: sudo rpm -e mapr-patch
- On SUSE: sudo zypper remove mapr-patch
- On Ubuntu: sudo apt-get -y remove mapr-patch
Install the patch using one of the following commands:
- On CentOS/RedHat: sudo rpm -ivh mapr-patch-<new_patch_number>.rpm
- On SUSE: sudo zypper install mapr-patch-<new_patch_number>.rpm
- On Ubuntu: sudo dpkg -i mapr-patch-<new_patch_number>.deb
Start the Warden and ZooKeeper (if installed) services:
1. If ZooKeeper is installed on the node, run this command to start ZooKeeper:
```
sudo service mapr-zookeeper start
```
2. To start Warden, run this command:
```
sudo service mapr-warden start
```
To verify that the patch was installed successfully, run one of the following commands:
- On CentOS/Redhat or SUSE: sudo rpm -ql mapr-patch-<new_patch_number>
- On Ubuntu: sudo dpkg -l | grep mapr-patch-<new_patch_number>