MySQL Router HA with Keepalived | MySQL InnoDB Cluster

keepalive provides frameworks for both load balancing and high availability. The load balancing framework relies on the well-known and widely used Linux Virtual Server (IPVS) kernel module, which provides Layer 4 load balancing. Keepalived implements a set of health checkers to dynamically and adaptively maintain and manage load-balanced server pools according to their health. High availability is achieved by the Virtual Redundancy Routing Protocol (VRRP).

• In short, Keepalived provides two main functions:
  • Health checking for LVS systems
  • Implementation of the VRRPv2 stack to handle load balancer failover

mysqlrouter –bootstrap innodbcluster@mysql2 –user mysqlrouter –force

Strong_Password1!

systemctl enable mysqlrouter

##ON both servers

sudo yum -y install keepalived

mv /etc/keepalived/keepalived.conf /etc/keepalived/keepalived.conf.back

vi /etc/keepalived/keepalived.conf

############mysqlrouter 1 ##############

vrrp_script chk_mysqlrouter {
script “/bin/killall -0 /usr/bin/mysqlrouter” # check the haproxy process
interval 2 # every 2 seconds
weight 2 # add 2 points if OK
fall 2
}

vrrp_instance VI_1 {
state MASTER
interface enp0s3
virtual_router_id 50
priority 102
advert_int 1
virtual_ipaddress {
192.168.56.111
}
track_script {
chk_mysqlrouter
}
}

############ mysqlrouter 2 ##############

cript chk_mysqlrouter {
script “/bin/killall -0 /usr/bin/mysqlrouter” # check the haproxy process
interval 2 # every 2 seconds
weight 2 # add 2 points if OK
fall 2
}

vrrp_instance VI_2 {
state BACKUP
interface enp0s3
virtual_router_id 51
priority 101
advert_int 1
virtual_ipaddress {
192.168.56.111
}
track_script {
chk_mysqlrouter
}
}

systemctl start keepalived (on both servers)
systemctl enable keepalived
systemctl status keepalived
ip addr show

while [ 1 ] do
sleep 1
mysql -h 192.168.56.111 -P 6447 -uinnodbcluster -pStrong_Password1! \
-e “select @@hostname;”
done