Rocky_Linux_8
Sponsored Link

HAProxy : Layer 4 Load Balancing
2021/08/16
 
Configure HAProxy on Layer 4 Mode.
On this example, configure MariaDB backend like the following environment.
-----------+---------------------------+--------------------------+------------
           |                           |                          |
           |10.0.0.30                  |10.0.0.51                 |10.0.0.52
+----------+-----------+   +-----------+----------+   +-----------+----------+
|   [ dlp.srv.world ]  |   | [ node01.srv.world ] |   | [ node02.srv.world ] |
|        HAProxy       |   |   MariaDB Server#1   |   |   MariaDB Server#2   |
+----------------------+   +----------------------+   +----------------------+

[1] Configure HAProxy.
[root@dlp ~]#
vi /etc/haproxy/haproxy.cfg
# change [mode] value in [defaults] section

defaults
    mode            tcp

# define MariaDB for frontend, backend
frontend mysql-in
    bind *:3306
    default_backend backend_servers

backend backend_servers
    balance         roundrobin
    server          node01 10.0.0.51:3306 check
    server          node02 10.0.0.52:3306 check

[root@dlp ~]#
systemctl restart haproxy

[2] If SELinux is enabled, change boolean setting.
[root@dlp ~]#
setsebool -P haproxy_connect_any on

[3] If Firewalld is running, allow ports HAProxy listens.
[root@dlp ~]#
firewall-cmd --add-service=mysql

success
[root@dlp ~]#
firewall-cmd --runtime-to-permanent

success
[4] Verify working normally to access to frontend HAproxy Server.
[root@client ~]#
mysql -u rocky -p -h 10.0.0.30 -e "show variables like 'hostname';"

Enter password:
+---------------+------------------+
| Variable_name | Value            |
+---------------+------------------+
| hostname      | node01.srv.world |
+---------------+------------------+

[root@client ~]#
mysql -u rocky -p -h 10.0.0.30 -e "show variables like 'hostname';"

Enter password:
+---------------+------------------+
| Variable_name | Value            |
+---------------+------------------+
| hostname      | node02.srv.world |
+---------------+------------------+
Matched Content