Post-Installation Verification

After completing any installation method below, verify connectivity and reset credentials:

mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY 'SecureP@ssw0rd!';
Query OK, 0 rows affected (0.01 sec)

mysql> CREATE DATABASE app_database;
Query OK, 1 row affected (0.00 sec)

mysql> USE app_database;
Database changed

mysql> CREATE TABLE employees (emp_id INT, emp_name VARCHAR(20));
Query OK, 0 rows affected (0.02 sec)

mysql> INSERT INTO employees VALUES (1,'Alice'),(2,'Bob'),(3,'Charlie');
Query OK, 3 rows affected (0.01 sec)
Records: 3  Duplicates: 0  Warnings: 0

mysql> SELECT * FROM employees;
+--------+----------+
| emp_id | emp_name |
+--------+----------+
|      1 | Alice    |
|      2 | Bob      |
|      3 | Charlie  |
+--------+----------+
3 rows in set (0.00 sec)

Method 1: YUM Repository Installation

For servers with internet access, use the official Oracle MySQL repository:

Download and install the release package:

[admin@db-server ~]$ wget https://dev.mysql.com/get/mysql57-community-release-el7-11.noarch.rpm
[admin@db-server ~]$ sudo rpm -Uvh mysql57-community-release-el7-11.noarch.rpm

Modify repository configuration to enable MySQL 5.7 and disable 8.0:

[admin@db-server ~]$ sudo sed -i 's/enabled=1/enabled=0/' /etc/yum.repos.d/mysql-community.repo
[admin@db-server ~]$ sudo yum-config-manager --enable mysql57-community

Install the database server:

[admin@db-server ~]$ sudo yum install -y mysql-community-server mysql-community-devel

Retrieve the temporary root password from logs:

[admin@db-server ~]$ sudo grep 'temporary password' /var/log/mysqld.log
2024-01-15T08:30:12.123456Z 1 [Note] A temporary password is generated for root@localhost: 9Xk#mP2$vLqR

[admin@db-server ~]$ mysql -u root -p'9Xk#mP2$vLqR'

Method 2: Offline RPM Bundle Installation

For air-gapped enviornments, deploy using the official RPM bundle:

Extract the package collection:

[admin@db-server ~]$ mkdir -p /opt/mysql-packages && cd /opt/mysql-packages
[admin@db-server ~]$ tar -xvf mysql-5.7.44-1.el7.x86_64.rpm-bundle.tar
[admin@db-server ~]$ ls *.rpm
mysql-community-client-5.7.44-1.el7.x86_64.rpm
mysql-community-common-5.7.44-1.el7.x86_64.rpm
mysql-community-libs-5.7.44-1.el7.x86_64.rpm
mysql-community-server-5.7.44-1.el7.x86_64.rpm

Install all packages locally:

[admin@db-server ~]$ sudo yum localinstall -y mysql-community-*.rpm

Complete initial setup:

[admin@db-server ~]$ sudo grep 'password' /var/log/mysqld.log | tail -1
[admin@db-server ~]$ mysql -uroot -p'TemporaryPass123!'

Method 3: Generic Binary Installation

Compile from generic Linux binaries for custom deployment paths:

Prepare system dependencies:

[admin@db-server ~]$ sudo rpm -e mariadb-libs --nodeps
[admin@db-server ~]$ sudo yum install -y libaio numactl-libs ncurses-devel

Deploy binary distribution:

[admin@db-server ~]$ cd /usr/local/src
[admin@db-server ~]$ sudo tar -zxvf mysql-5.7.44-linux-glibc2.12-x86_64.tar.gz
[admin@db-server ~]$ sudo mv mysql-5.7.44-linux-glibc2.12-x86_64 /usr/local/mysql57
[admin@db-server ~]$ sudo ln -s /usr/local/mysql57 /usr/local/mysql

Create data directories and service account:

[admin@db-server ~]$ sudo mkdir -p /var/db/mysql/{data,logs,tmp}
[admin@db-server ~]$ sudo groupadd -r dbadmin
[admin@db-server ~]$ sudo useradd -r -g dbadmin -M -s /sbin/nologin dbadmin
[admin@db-server ~]$ sudo chown -R dbadmin:dbadmin /var/db/mysql /usr/local/mysql
[admin@db-server ~]$ sudo ln -s /usr/local/mysql/bin/* /usr/local/bin/

Initialize the data directory:

[admin@db-server ~]$ sudo /usr/local/mysql/bin/mysqld --initialize-insecure \
  --user=dbadmin --basedir=/usr/local/mysql --datadir=/var/db/mysql/data

Configure instance settings in /etc/mysql57.cnf:

[client]
port=3306
socket=/var/db/mysql/mysql.sock

[mysqld]
user=dbadmin
basedir=/usr/local/mysql
datadir=/var/db/mysql/data
port=3306
socket=/var/db/mysql/mysql.sock
pid-file=/var/db/mysql/logs/mysqld.pid
log-error=/var/db/mysql/logs/error.log
character-set-server=utf8mb4
collation-server=utf8mb4_unicode_ci
default-storage-engine=InnoDB
symbolic-links=0

Create systemd service file /etc/systemd/system/mysql57.service:

[Unit]
Description=MySQL 5.7 Database Server
After=network.target

[Service]
Type=forking
User=dbadmin
Group=dbadmin
ExecStart=/usr/local/mysql/bin/mysqld --defaults-file=/etc/mysql57.cnf --daemonize
ExecReload=/bin/kill -HUP $MAINPID
ExecStop=/bin/kill -QUIT $MAINPID
PIDFile=/var/db/mysql/logs/mysqld.pid
LimitNOFILE=65535
Restart=on-failure

[Install]
WantedBy=multi-user.target

Start and enable the service:

[admin@db-server ~]$ sudo systemctl daemon-reload
[admin@db-server ~]$ sudo systemctl enable --now mysql57
[admin@db-server ~]$ mysql -uroot -e "ALTER USER 'root'@'localhost' IDENTIFIED BY 'NewSecurePass123!';"

Troubleshooting Common Isssues

Service Start Failure If systemctl start mysql57 exits with error code 1, verify PID directory permissoins:

[admin@db-server ~]$ sudo mkdir -p /var/run/mysqld
[admin@db-server ~]$ sudo chown dbadmin:dbadmin /var/run/mysqld
[admin@db-server ~]$ sudo systemctl restart mysql57

Missing Temporary Password When the error log contains no temporary password:

[admin@db-server ~]$ sudo rm -rf /var/db/mysql/data/*
[admin@db-server ~]$ sudo /usr/local/mysql/bin/mysqld --initialize \
  --user=dbadmin --datadir=/var/db/mysql/data
[admin@db-server ~]$ sudo grep 'temporary password' /var/db/mysql/logs/error.log

Socket Connection Errors When encountering ERROR 2002 (HY000): Can't connect through socket:

[admin@db-server ~]$ ln -s /var/db/mysql/mysql.sock /tmp/mysql.sock

Production Configuration Reference

Optimized my.cnf template for server deployment:

[client]
port=3306
socket=/var/db/mysql/mysql.sock
default-character-set=utf8mb4

[mysql]
prompt="\\u@\\h [\\d]> "
no-auto-rehash

[mysqld]
# Core Settings
user=dbadmin
port=3306
basedir=/usr/local/mysql
datadir=/var/db/mysql/data
socket=/var/db/mysql/mysql.sock
pid-file=/var/db/mysql/logs/mysqld.pid
default-storage-engine=InnoDB
default-authentication-plugin=mysql_native_password

# Logging Configuration
log-error=/var/db/mysql/logs/error.log
slow-query-log=1
slow-query-log-file=/var/db/mysql/logs/slow.log
long-query-time=1
log-timestamps=SYSTEM
log-queries-not-using-indexes=1

# InnoDB Tuning
innodb-buffer-pool-size=2G
innodb-buffer-pool-instances=4
innodb-log-file-size=256M
innodb-log-files-in-group=3
innodb-flush-log-at-trx-commit=1
innodb-file-per-table=1
innodb-flush-method=O_DIRECT
innodb-large-prefix=1

# Connection Handling
max-connections=300
max-user-connections=100
wait-timeout=600
interactive-timeout=600
max-allowed-packet=64M

# Replication Settings
server-id=1001
log-bin=/var/db/mysql/logs/binlog
binlog-format=ROW
expire-logs-days=7
gtid-mode=ON
enforce-gtid-consistency=ON
log-slave-updates=1

# Query Cache (disabled for 5.7 performance)
query-cache-type=0
query-cache-size=0

# Table Settings
table-open-cache=2048
table-definition-cache=1024
tmp-table-size=64M
max-heap-table-size=64M

# Security
skip-name-resolve
local-infile=0
symbolic-links=0
require-secure-transport=OFF