(13.9) Redundant deployment with docker compose

Wallboard deployment

Follow this guide to deploy the Wallboard on two machines.

Virtual IP configuration

Repeat the following steps for all the machines in the HA cluster.

1. Download keepalived.sh script and place it in /root directory.

2. Give execute permission and execute the script: 

   # chmod +x keepalived.sh # ./keepalived.sh

3. Configure keep.env file inside /root/keep-alived folder

   Name	Description
   KEEPALIVED_UNICAST_PEERS	IPs of the machines in the cluster. On each machine, this variable should have the IP of the other machine in HA.
   KEEPALIVED_VIRTUAL_IPS	Virtual IP of the cluster. It should be available in the LAN. For example: 192.168.1.245
   KEEPALIVED_PRIORITY	The priority of the node. Instances with lower numbers will have a higher priority. It can take any value from 1-255.
   KEEPALIVED_INTERFACE	Name of the network interface with which your machine is connected to the network. On CentOS, ifconfig or ip addr will show all the network interfaces and assigned addresses.
   CLEARANCE_TIMEOUT	Corresponds to the initial startup time of the application in seconds which is being monitored by keepalived. A nominal value of 60-120 is good enough
   KEEPALIVED_ROUTER_ID	Do not change this value.
   SCRIPT_VAR	This script is continuously polled after 2 seconds. Keepalived relinquishes control if this shell script returns a non-zero response. For wallboard, it should be: pidof dockerd && wget -O index.html https://localhost:443

4. Give the execute permission and execute the script: 

   # chmod +x keep-command.sh # ./keep-command.sh