Failover support in Applications Manager
Failover is an alternate Application High availability (HA) mode that facilitates automatic switching to a secondary/ backup server, database, or network when the primary system breaks down, or is unavailable due to maintenance. Configuring failover support for applications like Applications Manager can not only help achieve uninterrupted availability, but also ensure hassle-free monitoring of mission-critical servers that may be important to your business.
Applications Manager HA / Failover is available by default for free in all the editions. (Professional/Enterprise).
Architecture Diagram of Applications Manager
Failover Mechanism:
As you can see in the above diagram, Applications Manager's failover is a dual server, single database system. There are two servers - a primary server and a secondary server along with a common database. Every time the primary server interacts with the database, the secondary server listens. If for some reason, there have been no interactions between the primary server and the database (and if an entry hasn't been added in the failover table in the last 60 seconds), the secondary server understands that there might be a problem and hence automatically starts acting as the primary server. Once the primary server has been restarted, it then starts acting as the secondary server.
When failover happens and the secondary server becomes active, the IP of the primary server might've changed and you will have to access the IP of the secondary server which will now act as the primary server.
The virtual IP address is not tied to a specific server. It helps access the available server and enables smooth transitions during failover.
Note: Also, it is recommended that you enable replication for the backend database to avoid sudden database unavailability and minimize downtime as much as possible.
New to ADSelfService Plus?
Related Articles
Applications Manager default tomcat is down
If your Tomcat Monitor is down, it could probably be due to changes in Hostname/IP address of the machine in which Applications Manager is installed. You can verify the same using the steps given below: Navigate to ...Configuring AWS Application Load Balancer (ALB) for routing traffic to Applications Manager Failover setup
Step 1: Failover Setup Follow this document and set up the Applications Manager Failover. It is recommended that you deploy the database server in the Cloud infrastructure as well. To use PGSQL, you can use bundled PGSQL with Applications Manager. To ...Configuring Applications Manager Failover setup across multiple regions/networks in AWS
To configure APM Failover setup in a single region using Amazon Application Load Balancer, refer to this Knowledge Base. Agenda: To configure APM Failover between multiple networks, consider the following scenarios: Establish communication between ...Authentication Methods in Applications Manager
Authentication involves validating an incoming user to facilitate the access to a specific resource. There are various authentication methods that you can use - based on the requirements and usage. In recent times, numerous organizations are ...ManageEngine Applications Manager High Availability setup with dual database (MySQL).
Apart from the Failover setup, which uses a single database and dual Application Server, we also support a failover with dual database and Application Server. Failover support requires you to configure Applications Manager Secondary (Standby server) ...