HA Configuration

Installation:

On machine1 and machine2 install Heartbeat and needed utilities. You may need to review the packages you have available using ‘yum list | grep drbd’. These are for CentOS 5.5. You may also need to reboot after this step.

# yum -y install gnutls*
# yum -y install ipvsadm*
# yum -y install heartbeat*
# yum -y install heartbeat.x86_64

Configuration:

Edit /etc/sysctl.conf and set net.ipv4.ip_forward = 1

# vi /etc/sysctl.conf

Controls IP packet forwarding net.ipv4.ip_forward = 1

# /sbin/chkconfig --level 2345 heartbeat on
# /sbin/chkconfig --del ldirectord

Configure HA:

You need to setup the following configuration files on both machines:

# vi /etc/ha.d/ha.cf

#/etc/ha.d/ha.cf content
debugfile /var/log/ha-debug
logfile /var/log/ha-log
logfacility local0
keepalive 2
deadtime 30
warntime 10
initdead 120
udpport 694 # If you have multiple HA setup in same network.. use different ports
bcast eth0 # Linux
auto_failback on # This will failback to machine1 after it comes back
ping 192.168.2.1 # The gateway
apiauth ipfail gid=haclient uid=hacluster
node db1.grennan.com
node db2.grennan.com

On both machines

NOTE: Assuming 192.168.2.15 is virtual IP for your MySQL resource and mysqld is the LSB resource agent. The host name (db2) should be the secondary server’s name.

# vi /etc/ha.d haresources

# /etc/ha.d/haresources content
db2.grennan.com LVSSyncDaemonSwap::master Paddr2::192.168.2.15/24/eth0 rbddisk::db Filesystem::/dev/drbd1::/data::ext3 mysqld

# vi /etc/ha.d/authkeys

#/etc/ha.d/authkeys content
auth 2
2 sha1 BigSecretKeyks9wjwlf9gskg905snvl

Now, make your authkeys secure:

# chmod 600 /etc/ha.d/authkeys

Check your work:

On both machines, one at a time, stop MySQL and make sure MySQL does not start when the system reboots (init 6).

If it does, you may need to remove it from the init process with:

# /sbin/chkconfig --level 2345 MySQL off

Start Heartbeat.

# service heartbeat start

These commands will give you status about this LVS setup:

# /etc/ha.d/resource.d/LVSSyncDaemonSwap master status
# ip addr sh
# service heartbeat status
# df
# service mysqld status

Access your HA-MySQL server like:

# mysql –h 192.168.2.15

Shutdown machine1 to see MySQL up on machine2. ‘shutdown now’

Start machine1 to see MySQL back on machine1.