./bitnami-lampstack-7.2.26-0-linux-x64-installer.run --help

./bitnami-lampstack-7.2.26-0-linux-x64-installer.run --prefix /opt/bitnami/lampstack-7.2.26.0 --disable-components varnish,zendframework,symfony,codeigniter,cakephp,smarty,laravel --base_password testpass --apache_server_port 9955 --apache_server_ssl_port 9943  --mysql_port 3309 --mode unattended

$ cd /opt/bitnami/lampstack-7.2.26.0 && ./ctlscript.sh status  && ./ctlscript.sh stop
apache already running
mysql already running
Syntax OK
/opt/bitnami/lampstack-7.2.26.0/apache2/scripts/ctl.sh : httpd stopped
/opt/bitnami/lampstack-7.2.26.0/mysql/scripts/ctl.sh : mysql stopped

$ mv mysql mysql_original
$ mkdir mysql && mkdir mysql/{tmp,run,data}
$ cp -r mysql_original/scripts mysql/
$ cp mysql_original/my.cnf mysql ##it should be adapted to your previous configuration, but keep defined directory variables
$ wget https://downloads.mysql.com/archives/get/p/23/file/mysql-5.7.38-linux-glibc2.12-x86_64.tar.gz
$ tar -xzf mysql-5.7.38-linux-glibc2.12-x86_64.tar.gz  -C mysql --strip-components 1 ##untar archive contents into mysql skipping root directory
$ ln -s /opt/bitnami/lampstack-7.2.26.0/mysql/bin/mysqld /opt/bitnami/lampstack-7.2.26.0/mysql/bin/mysqld.bin ##or fix mysql ctl.sh to use mysqld instead of mysqld.bin

$ cp -R old_data/ /opt/bitnami/lampstack-7.2.26.0/mysql/
$ ./opt/bitnami/lampstack-7.2.26.0/ctlscript.sh start mysql

 InnoDB: Unsupported redo log format. The redo log was created with MariaDB 10.2.44. Please follow the instructions at http://dev.mysql.com/doc/refman/5.7/en/upgrading-downgrading.html

[ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery

[ERROR] InnoDB: Page [page id: space=0, page number=734] log sequence number 3261161573 is in the future! Current system log sequence number 3221898782.
[ERROR] InnoDB: Your database may be corrupt or you may have copied the InnoDB tablespace but not the InnoDB log files. Please refer to http://dev.mysql.com/doc/refman/5.7/en/forcing-innodb-recovery.html for information about forcing recovery.

$ vi mysql/scripts/ctl_upgrade.sh

#!/bin/sh
MSQLPATH=/opt/bitnami/lampstack-7.2.26.0/mysql
MYSQL_PIDFILE=$MSQLPATH/run/mysqld.pid

MYSQL_START="$MSQLPATH/bin/mysql_upgrade --defaults-file=$MSQLPATH/my.cnf --socket=$MSQLPATH/tmp/mysql.sock --verbose"

$MYSQL_START >$MSQLPATH/data/mysqld-update.log 2>&1

$ ./mysql/scripts/ctl_upgrade.sh
$ ./mysql/scripts/ctl.sh stop && ./mysql/scripts/ctl.sh start

$ vi /opt/bitnami/mysqldump.sh

#!/bin/sh
## Dump DB with no DB name in two rows:
## 1. dump structure with routines and no data
## 2. dump only data in ansi mode
## I avoid dumping with auto creating database to avoid collisions with existing databases on import.
MYSQL_BIN=mysqldump ##note, here i use old mysql binary available globally
PASSWORD=
HOST=$1
USER=root
DATABASE=$2

IGNORED_TABLES_STRING='' #if you want to skip some tables from dumping

now="$(date +'%d_%m_%Y_%H_%M')"
filename="${DATABASE}_db_backup_$now.sql"
backupfolder="./mysqldump"
logfile="$backupfolder/"backup_log_"$(date +'%Y_%m')".txt

echo "Dump structure started at $(date +'%d-%m-%Y %H:%M:%S')" >> "$logfile"
    $MYSQL_BIN --host=${HOST} --user=${USER} --password=${PASSWORD} --no-create-db ${DATABASE} --single-transaction --no-data --routines --log-error $logfile > $backupfolder/${DB_FILE} 
echo "Dump structure finished at $(date +'%d-%m-%Y %H:%M:%S')" >> "$logfile"

echo "Dumping contents"
##note dumped db will be in ansi mode, for better [compatibility][5] 
$MYSQL_BIN --compatible=ansi --host=${HOST} --user=${USER} --password=${PASSWORD} --no-create-db ${DATABASE} --no-create-info --skip-triggers ${IGNORED_TABLES_STRING} --log-error $logfile >> $backupfolder/${DB_FILE} 

$ cd /opt/bitnami && mkdir mysqldump && sh mysqldump.sh localhost db_to_dump
## stop old lampp services
$ ./opt/lampp/ctlscript.sh stop

$ vi /opt/bitnami/mysqlrestore.sh

#!/bin/sh
## Note here we use lampstack MySQL binary (not added to PATH)
MYSQL_BIN="/opt/bitnami/lampstack-7.2.26.0/mysql/bin/mysql --socket=/opt/bitnami/lampstack-7.2.26.0/mysql/tmp/mysql.sock"

PASSWORD=
filename="${1}"
USER=root
DATABASE=$2

now="$(date +'%d_%m_%Y_%H_%M')"

echo "Creating DB $DATABASE"
$MYSQL_BIN --user=$USER --password=$PASSWORD -e "CREATE DATABASE $DATABASE;"

MYSQL_BIN -u $USER --password=$PASSWORD $DATABASE < $filename

$ cd /opt/bitnami/lampstack-7.2.26.0/mysql/scripts && cp ctl.sh ctl_init.sh && vi ctl_init.sh
change MYSQL_START to 
MYSQL_START="/opt/bitnami/lampstack-7.2.26.0/mysql/bin/mysqld --socket=/opt/bitnami/lampstack-7.2.26.0/mysql/tmp/mysql.sock  --datadir=/opt/bitnami/lampstack-7.2.26.0/mysql/data --log-error=/opt/bitnami/lampstack-7.2.26.0/mysql/tmp/mysqld_init.log  --pid-file=$MYSQL_PIDFILE --lower-case-table-names=1 --user=mysql --initialize"
 NB! if you need root without password use --initialize-insecure

$ ./ctl_init.sh start
$ ./ctl.sh start
$ cd /opt/bitnami && ./mysqlrestore.sh mysqldump/dumped_file.sql db_new_name

 $ cd /opt && mkdir mariadb && mkdir mariadb/10.2.44-systemd 
 $ wget https://archive.mariadb.org/mariadb-10.2.44/bintar-linux-systemd-x86_64/mariadb-10.2.44-linux-systemd-x86_64.tar.gz
 $ tar -xzf mariadb-10.2.44-linux-systemd-x86_64.tar.gz -C 10.2.44-systemd --strip-components 1 
 $ cd 10.2.44-systemd && mkdir {tmp,run,data}
 $ cp /opt/bitnami/lampstack-7.2.26.0/mysql/scripts scripts
 $ cp /opt/bitnami/lampstack-7.2.26.0/mysql/my.cnf my.cnf
 $ ln -s /opt/mariadb/10.2.44-systemd /opt/bitnami/lampstack-7.2.26.0/mariadb

 At this point bitnami is aware that mariab module is installed, yet we need to update paths in copied ctl scripts to point to mariadb.

 $ cd scripts
 $ grep -rlZ "/opt/bitnami/lampstack-7.2.26.0/mysql" . ../my.cnf | xargs -0 sed -i 's/\/opt\/bitnami\/lampstack-7.2.26.0\/mysql/\/opt\/mariadb\/10.2.44-systemd/g'
 
 However, PhpMyAdmin will fail to connect, because in conf it points to mysql socket. Workaround is to create mariadb socket into mysql dir.

 $ vi ctl.sh
  In start_mysql() function in success clause (ERR -eq 0) add 
  ln -s/opt/mariadb/10.2.44-systemd/tmp/mysql.sock /opt/bitnami/lampstack-7.2.26.0/mysql/tmp/mysql.sock

  And in stop_mysql() in (RUNNING -eq 0) clause put
  rm /opt/bitnami/lampstack-7.2.26.0/mysql/tmp/mysql.sock

 Now you can run both MariaDB and MySQL and easily control them via manager.

$ sudo vi /etc/systemd/system/xampp.target
[Unit]
Description=Lampp target 
Requires=multi-user.target
After=multi-user.target
AllowIsolate=yes

$ sudo vi /etc/systemd/system/xampp@.service
[Unit]
Description=Start Xampp module: %I
PartOf=xampp.target

[Service]
Type=simple
User=your_username
ExecStart=/opt/bin/xampp_ctl.sh start %i
ExecStop=/opt/bin/xampp_ctl.sh stop %i 
Restart=on-failure
RemainAfterExit=yes

[Install]
WantedBy=xampp.target

$ daemon-reload
$ systemctl enable xampp@apache  ## for service name after @ use ctlscript tags (check by calling ctlscript.sh help)
$ systemctl enable xampp@mariadb ## to start mariadb by default
$ systemctl enable xampp.target
$ systemctl disable xampp.service ## old xampp service
$ ln -s /opt/bitnami/lampstack-7.2.26.0/ctlscript.sh /opt/bin/xampp_ctl.sh
$ systemctl start xampp.target