Upgrade Distributed API and DB server to v5.2

These steps are for a Distributed API Server with the database on the API server.

Abiquo will upgrade to new versions of RabbitMQ and MySQL that require a manual upgrade path of dependencies.

These steps are for a server that contains RabbitMQ AND MySQL

Remove the Erlang and Galera packages.

yum remove erlang* galera
yum clean all && yum makecache

Install new RabbitMQ and MariaDB server
```
yum install rabbitmq-server MariaDB-server
```
Before you confirm, check that the packages will be installed from the abiquo-base repository
1. rabbitmq-server: 3.8.2.1
2. MariaDB-server: 10.4.10.1
Upgrade Abiquo to 5.2.x
```
yum update
```
Before you confirm, check the following packages will be installed from the abiquo-base repository:
1. jdk: 11.0.6u10
2. redis: 5.0.7.1

After the update, check versions

Click here to show/hide steps to check versions

Check that the symbolic link to the latest version of Java points to Java 11 on Monolithic Server or Datanode

# cd /usr/java
# ll
latest -> /usr/java/jdk-11.0.6+10

Check that the correct Tomcat version will be used on the Monolithic Server

# cd /opt/abiquo/tomcat/bin
# sh version.sh
Using CATALINA_BASE:   /opt/abiquo/tomcat
Using CATALINA_HOME:   /opt/abiquo/tomcat
Using CATALINA_TMPDIR: /opt/abiquo/tomcat/temp
Using JRE_HOME:        /usr
Using CLASSPATH:       /opt/abiquo/tomcat/bin/bootstrap.jar:/opt/abiquo/tomcat/bin/tomcat-juli.jar
NOTE: Picked up JDK_JAVA_OPTIONS:  --add-opens=java.base/java.lang=ALL-UNNAMED --add-opens=java.base/java.io=ALL-UNNAMED --add-opens=java.rmi/sun.rmi.transport=ALL-UNNAMED
Server version: Apache Tomcat/9.0.33
Server built:   Mar 11 2020 09:31:38 UTC
Server number:  9.0.33.0
OS Name:        Linux
OS Version:     3.10.0-1160.15.2.el7.x86_64
Architecture:   amd64
JVM Version:    11.0.6+10
JVM Vendor:     AdoptOpenJDK

On the Monolithic Server in the JDK folder, check certificate migration for AM download. The API Server certificate should be listed for Java 11 with its FQDN. You may need to enter the storepass option to supply the password and you can use the alias option to search for the hostname or FQDN of your server

# cd /usr/java/jdk-11.0.6+10/lib/security
# keytool -list -keystore cacerts -alias (hostname or fqdn)

For example

sudo keytool -list -keystore cacerts -alias abiquo.example.com

Enable and start the new services

systemctl enable mariadb
systemctl enable rabbitmq-server
systemctl start mariadb
systemctl start rabbitmq-server

Upgrade MySQL
```
mysql_upgrade
```
The mysql_upgrade step may detect errors that trigger messages such as the following:
kinton_accounting.ACCOUNT_PERIOD_USAGE_VW Error : Column count of mysql.proc is wrong. Expected 21, found 20. Created with MariaDB 100129, now running 100410. Please use mysql_upgrade to fix this error
These messages are expected and this same mysql_upgrade process will automatically fix these errors in its next stages.
Check that the mysql_upgrade process completes correctly.
Check that your hostname is in your DNS or in your /etc/hosts file
Upgrade the Abiquo API databases
```
abiquo-db [-h DB hostname] [-P DB port] [-u user] [-p password] update
```
If the liquibase update fails with a message similar to the following:
Liquibase update Failed: Validation Failed:
1 change sets check sum
src/X.X.X-XX/kinton-X.X.X.xml::ABICLOUDPREMIUM-XXXX-XxxxxxxxXXxXxxxxxxXxxxxx::XXXXXXXXX is now: 7:ee2fa6e058ec76c7abf801567898917d
For more information, use the --logLevel flag
Do the following steps
1. Clear the database checksums
  abiquo-db clearCheckSums
2. Retry the above abiquo-db update command.
Change file owners to tomcat user
```
chown -R tomcat /opt/abiquo
```