This is the documentation for CDH 5.1.x. Documentation for other versions is available at Cloudera Documentation.

Upgrading ZooKeeper from CDH 4 to CDH 5

To upgrade ZooKeeper from CDH 4 to CDH 5, uninstall the CDH 4 version (if you have not already done so) and then install the CDH 5 version. Do the following on each server.

Note: If you have already performed the steps to uninstall CDH 4 described under Upgrading from CDH 4 to CDH 5, you can skip Step 1 below and proceed with Step 2.

CAUTION:

On Ubuntu systems, make sure you remove HBase before removing ZooKeeper; otherwise your HBase configuration will be deleted. This is because hadoop-hbase depends on hadoop-zookeeper, and so purging hadoop-zookeeper will purge hadoop-hbase.

Step 1: Remove ZooKeeper

Stop the ZooKeeper server:
```
$ sudo service zookeeper-server stop
```
or
```
$ sudo service zookeeper stop
```
depending on the platform and release.
Remove CDH 4 ZooKeeper
To remove ZooKeeper on Red Hat-compatible systems:
```
$ sudo yum remove zookeeper-server
```
To remove ZooKeeper on Ubuntu and Debian systems:
```
$ sudo apt-get remove zookeeper-server
```
To remove ZooKeeper on SLES systems:
```
$ sudo zypper remove zookeeper-server
```

Step 2: Install the ZooKeeper Base Package

See Installing the ZooKeeper Base Package.

Step 3: Install the ZooKeeper Server Package

See Installing the ZooKeeper Server Package.

Important: Configuration files

If you install a newer version of a package that is already on the system, configuration files that you have modified will remain intact.
If you uninstall a package, the package manager renames any configuration files you have modified from <file> to <file>.rpmsave. If you then re-install the package (probably to install a new version) the package manager creates a new <file> with applicable defaults. You are responsible for applying any changes captured in the original configuration file to the new configuration file. In the case of Ubuntu and Debian upgrades, you will be prompted if you have made changes to a file for which there is a new version; for details, see Automatic handling of configuration files by dpkg.

Step 5: Restart the Server

See Installing the ZooKeeper Server Package for instructions on starting the server.

Page generated September 3, 2015.