Post-Upgrade Steps for Hue

Complete the following steps after you upgrade Hue with or without the MapR Installer:

About this task

Procedure

To configure the Hue-livy package after upgrading, see Integrate Hue 3.10+ With Spark 2.
After upgrading on Ubuntu, remove the mapr-hue-base package:
```
apt-get remove mapr-hue-base
```
Copy the changes that you made for required services in your existing hue.ini file into the latest version of the file:
```
/opt/mapr/hue/hue-<version>/desktop/conf/hue.ini
```
NOTE: Hue 3.9 uses the old Query editor to work with Hive and Impala queries, and introduces new Spark Notebooks. Hue 3.10+ uses Notebooks as a replacement for the old Query editor for Hive and Impala. If you are upgrading to Hue 3.10+, and you want to have access to your saved queries in the old Hive or Impala Query editor, you need to configure Hue to use the old Query editor. To do this, set the use_new_editor property in the hue.ini file to false. For example:
```
[desktop]
...
  # Choose whether to show the new SQL editor.
  use_new_editor=false
```
If Hue is installed on CentOS/RedHat 7.x nodes, complete the following steps:
1. Create the following symlink to the Cyrus SASL library:
```
ln -s /lib64/libsasl2.so.3.0.0 /lib64/libsasl2.so.2
```
2. If Hue is also configured to use a MySQL database, run the following commands to install MariaDB and the Redhat 6 compatibility library:
```
yum install mariadb  
 rpm -ivh --nodeps http://yum.mariadb.org/<mariadb_version>/rhel7-amd64/rpms/MariaDB-<mariadb_version>-centos7-x86_64-compat.rpm 
```

If you use SQLite as the Hue database, load its backup:

If the Hue node runs on Ubuntu, install sqlite3:
```
apt-get install sqlite3
```

Run the following commands:

cd /opt/mapr/hue/hue-<new_version>/desktop
mv desktop.db desktop.db.old
sqlite3 desktop.db < ~/dump-hue-<old_version>-sqlite.bak
sqlite3 desktop.db
DELETE FROM django_content_type;

Update the old database schema so that it is compatible with the new upgraded version:
```
source /opt/mapr/hue/hue-<new_version>/build/env/bin/activate
hue syncdb --noinput
hue migrate --merge
deactivate
```
For example, run the following commands to update the database schema so that it is compatible with Hue 3.10+:
```
source /opt/mapr/hue/hue-3.10.0/build/env/bin/activate
hue syncdb --noinput
hue migrate --merge
deactivate
```
If you are using MySQL, PostgreSQL, or Oracle, and you have trouble with the database during the Hue upgrade, you can restore your data from the backup that you created during the Pre-Upgrade Steps for Hue:
```
source /opt/mapr/hue/hue-<new_version>/build/env/bin/activate
hue loaddata --ignorenonexistent ~/dump-hue-<old_version>.json
deactivate
```
For upgrades performed without the MapR Installer: If you are using Hadoop MRv1, complete the following steps to establish communication between Hue and the JobTracker processes:
1. Remove existing Hue plugins from the MapReduce lib directory:
```
rm /opt/mapr/hadoop/hadoop-0.20*/lib/hue-plugins-*.jar
```
2. Copy new Hue plugins to the MapReduce lib directory:
```
cp /opt/mapr/hue/hue-<version>/desktop/libs/hadoop/java-lib/hue-plugins-*.jar /opt/mapr/hadoop/hadoop-0.20*/lib/
```
  For example, run the following commands to copy the Hue plugin for Hue 3.10+:
```
cp /opt/mapr/hue/hue-3.10.0/desktop/libs/hadoop/java-lib/hue-plugins-*.jar /opt/mapr/hadoop/hadoop-0.20*/lib/
```
3. Restart the JobTracker services:
```
maprcli node services -jobtracker restart -nodes <ip_addresses>
```
Run configure.sh -R:
```
/opt/mapr/server/configure.sh -R
```
If you do not complete this step, Hue may fail to start and the MCS may still display references to the Hue version that you upgraded from.

Restart the Hue service:

maprcli node services -name hue -action restart -nodes <ip_address>