How Do I Enable Remote Access To MySQL Database Server?
By
default remote access to the MySQL database server is disabled for
security reasons. However, some time you need to provide remote access
to database server from home or a web server. If you want to remotely
access to the database server from the web server or home, follow this
quick tutorial.
Task: MySQL Server Remote Access
You need type the following commands which will allow remote connections.
Step # 1: Login Using SSH (if server is outside your data center)
First, login over ssh to remote MySQL database server:
ssh user@server1.cyberciti.biz
Step # 2: Edit my.cnf File
Once connected you need to edit the MySQL server configuration file my.cnf using a text editor such as vi.
- If you are using Debian Linux file is located at /etc/mysql/my.cnf location
- If you are using Red Hat Linux/Fedora/Centos Linux file is located at /etc/my.cnf location
- If you are using FreeBSD you need to create a file /var/db/mysql/my.cnf
Edit /etc/my.cnf, run:
# vi /etc/my.cnf
Step # 3: Once file opened, locate line that read as follows
[mysqld]
Make sure line skip-networking is commented (or remove line) and add following line
bind-address=YOUR-SERVER-IP
For example, if your MySQL server IP is 65.55.55.2 then entire block should be look like as follows:
[mysqld]
user = mysql
pid-file = /var/run/mysqld/mysqld.pid
socket = /var/run/mysqld/mysqld.sock
port = 3306
basedir = /usr
datadir = /var/lib/mysql
tmpdir = /tmp
language = /usr/share/mysql/English
bind-address = 65.55.55.2
# skip-networking
....
..
....
Where,
- bind-address : IP address to bind to.
- skip-networking
: Don’t listen for TCP/IP connections at all. All interaction with
mysqld must be made via Unix sockets. This option is highly recommended
for systems where only local requests are allowed. Since you need to
allow remote connection this line should be removed from my.cnf or put
it in comment state.
Step# 4 Save and Close the file
If you are using Debian / Ubuntu Linux, type the following command to restart the mysql server:
# /etc/init.d/mysql restart If you are using RHEL / CentOS / Fedora / Scientific Linux, type the following command to restart the mysql server:
# /etc/init.d/mysqld restart If you are using FreeBSD, type the following command to restart the mysql server:
# /usr/local/etc/rc.d/mysql-server stop
# /usr/local/etc/rc.d/mysql-server start OR
# /usr/local/etc/rc.d/mysql-server restart
Step # 5 Grant access to remote IP address
Connect to mysql server:
$ mysql -u root -p mysql
Grant access to a new database
If
you want to add a new database called foo for user bar and remote IP
202.54.10.20 then you need to type the following commands at mysql>
prompt:
mysql> CREATE DATABASE foo;
mysql> GRANT ALL ON foo.* TO bar@'202.54.10.20' IDENTIFIED BY 'PASSWORD';
How Do I Grant Access To An Existing Database?
Let
us assume that you are always making connection from remote IP called
202.54.10.20 for database called webdb for user webadmin, To grant
access to this IP address type the following command At mysql> prompt
for existing database, enter:
mysql> update db set Host='202.54.10.20' where Db='webdb';
mysql> update user set Host='202.54.10.20' where user='webadmin';
Step # 6: Logout of MySQL
Type exit command to logout mysql:
mysql> exit
Step # 7: Open port 3306
You need to open TCP port 3306 using iptables or BSD pf firewall.
A sample iptables rule to open Linux iptables firewall
/sbin/iptables -A INPUT -i eth0 -p tcp --destination-port 3306 -j ACCEPT
OR only allow remote connection from your web server located at 10.5.1.3:
/sbin/iptables -A INPUT -i eth0 -s 10.5.1.3 -p tcp --destination-port 3306 -j ACCEPT
OR only allow remote connection from your lan subnet 192.168.1.0/24:
/sbin/iptables -A INPUT -i eth0 -s 192.168.1.0/24 -p tcp --destination-port 3306 -j ACCEPT
Finally save all rules (RHEL / CentOS specific command):
# service iptables save
A sample FreeBSD / OpenBSD pf rule ( /etc/pf.conf)
pass in on $ext_if proto tcp from any to any port 3306
OR allow only access from your web server located at 10.5.1.3:
pass in on $ext_if proto tcp from 10.5.1.3 to any port 3306 flags S/SA synproxy state
Step # 8: Test it
From your remote system or your desktop type the following command:
$ mysql -u webadmin –h 65.55.55.2 –p Where,
- -u webadmin: webadmin is MySQL username
- -h IP or hostname: 65.55.55.2 is MySQL server IP address or hostname (FQDN)
- -p : Prompt for password
You can also use the telnet or nc command to connect to port 3306 for testing purpose:
$ echo X | telnet -e X 65.55.55.2 3306 OR
$ nc -z -w1 65.55.55.2 3306 Sample outputs:
Connection to 65.55.55.2 3306 port [tcp/mysql] succeeded!
