Configuring High Availability for Micetro Central

Failover instances of Micetro Central can be configured to build a High Availability (HA) cluster. For information about fine-tuning the settings for the Central High Availability cluster, refer to Micetro Central HA Tweaks.

Note

• To run Micetro in High Availability mode, you must be using the MS SQL or PostgreSQL database backend for Micetro. High Availability mode is not available for other database types.

• All participating Micetro Central HA servers should have NTP configured. Clocks that are out-of-sync can cause unwanted failovers.

When there are no HA members defined or if Micetro Central has not been configured for HA, a message will appear, indicating further configuration is necessary. This documentation provides instructions on how to configure HA in Micetro for versions 10.2 and above. If you need to use the management console (thick client), please refer to the documentation for version 10.1.

WindowsLinux

1. On the existing (or designated as primary) server running Micetro Central, edit the Micetro Central preferences file C:\ProgramData\Men and Mice\Central\preferences.cfg by adding the following XML-tag to the file:

<ClusterMemberName value="somename" />

somename is the unique name that will identify the Micetro Central instance in the High Availability cluster, e.g., “1”, “primary”, or “central1”. Here’s an example:

<ClusterMemberName value="primary" />

2. Restart the primary Central application from the command line:

• Open the Services window, e.g., by selecting Win + R, entering services.msc, and selecting OK.

• Locate the Men and Mice Central service, right-click on it, and select Start or Restart.

3. Log into the Micetro Web Application as “administrator” and go to Admin ‣ Configuration.

4. Select High Availability.

5. Enter the name of the first member server to match the name previously given and set the priority to 10. The name must match the name in the XML-tag ClustMemberName, e.g., as in the example above as primary.

6. Select Add Member.

   

7. Restart Micetro Central from the command line or through the services.msc:

• Open the Services window, e.g., by selecting Win + R, entering services.msc, and selecting OK.

• Locate the Men and Mice Central service, right-click on it, and select Start or Restart.

8. Log into the Web Application and navigate to Admin ‣ Configuration ‣ High Availability to verify that the current server is running with state Active.

   

9. Repeat steps 3–6 to add another member to the HA configuration, but now use a priority of 20 or higher, e.g., add a secondary server with the name “secondary” and a priority of 20.

   This adds the secondary server to the database. The configuration of the secondary Micetro Central server itself is done in the next steps.

10. On the newly added secondary server, install Micetro Central. If it’s already installed, make sure it’s stopped:

• Open the Services window by selecting Win + R, entering services.msc, and selecting OK.

• Locate the Men and Mice Central service, right-click on it, and select Stop to make sure it’s not running.

11. Copy the C:\ProgramData\Men and Mice\Central\preferences.cfg file from the first server (the Active one) to the new secondary server to replace the secondary server’s existing preferences.cfg file.

    • Change the XML-tag ClusterMemberName value to the name of the secondary that was set up in Step 9 and save the changed file.

Note

The only difference between the primary (Active) and secondary server’s preferences.cfg files should be the value of ClusterMemberName, e.g., secondary instead of primary.

12. Start Micetro Central on the secondary server:

• Open the Services window by selecting Win + R, entering services.msc, and selecting OK.

• Locate Men and Mice Central service, right-click on it, and select Start to make sure it’s running.

13. In the Web Application, navigate to Admin ‣ Configuration ‣ High Availability and verify that you now have two servers: one Active and one in a Standby state.

14. Create a round robin DNS name for the High Availability setup. This involves creating two A records with the same name, each with the IP address of the primary and secondary server. For example:

micetrocentral.example.com A 192.168.2.53
micetrocentral.example.com A 192.168.2.54

in which 192.168.2.53 is the primary and 192.168.2.54 is the secondary.

• Check whether the round robin name can be resolved, e.g., with Resolve-DNSName or nslookup on the Micetro Central servers.

15. Edit your Web Application C:\ProgramData\Men and Mice\Web Services\preferences.cfg file and add the following XML-tag:

<DefaultCentralServer value="your round robin record" />

For example:

<DefaultCentralServer value="micetrocentral.example.com" />

16. Restart the Men and Mice Web Services service through the services.msc.

Note

Repeat these steps for each High Availability failover relationship you’d like to add. The priority for each failover member should be unique and higher than the primary.

Proceed to Installing Micetro DNS Agents on Windows.

Editing HA member options

1. Log into the Micetro Web Application and go to Admin ‣ Configuration.

2. Select High Availability.

3. Hover over the server member and use the Row … menu to select one of the following options:

• Edit member: Change the name or priority of the server member in the HA cluster.

• Set active: Manually set the server to be the Active member of the HA cluster.

• Remove member: Remove the server member from the HA cluster.

Proceed to Installing Micetro DNS Agents on Windows or Installing Micetro DNS Agents on Linux.