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Phase 1 - Ensure existing configuration is good

There are several configuration items which need to be set in the slave configuration before proceeding.

Unfortunately, mysql 5.7 will use a different default binary log and relay log file name during the upgrade process (this is probably a bug), unless these steps are completed. 

Complete this procedure for all slaves (also both masters in master-master replication).

# Set variables for slave
cat <<EOFF >> /etc/my.cnf.d/jtel-slave.cnf
relay_log                       = mysqld-relay-bin
relay_log_index                 = mysqld-relay-bin.index
relay_log_info_file             = relay-log.info
EOFF


# Restart mysql
systemctl restart mysqld.service

Phase 2 - Update MySQL to 5.7

Remember - for replicated installations, start with the slaves first. Then update the masters. 

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# Clear versionlock table
yum versionlock clear

# Enable 5.7 
yum-config-manager --disable mysql56-community
yum-config-manager --enable mysql57-community
yum-config-manager --disable mysql80-community


# Update
yum update


# Start
service mysqld start

Start the MySQL Server (WITHOUT REPLICATION FOR SLAVES AND MASTER-MASTER)

Start the mysql Server without replication. Important: change the data directory if this is not in the standard location.

# Start - IMPORTANT - WITHOUT REPLICATION
# Change the data directory if this is not in the standard location.
systemctl set-environment MYSQLD_OPTS="--skip-slave-start"
systemctl start mysqld.service

Run mysql_upgrade

Either change the password in the following command, or simply use the -p option without specifying a password, and entering it at the prompt.

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Next restart the MySQL server.

systemctl stop mysqld.service
systemctl set-environment mysqld restartMYSQLD_OPTS=
systemctl start mysqld.service

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Phase 3 - Update MySQL to 8.0

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Phase

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4 - Configure Other Components

Update the JBOSS Server

The JBOSS server requires a new connector to attach to MySQL 8.x.

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