Failover Service (Version 13000 and above)

Failover Service (FOS) configuration ensures the availability of ServiceDesk Plus MSP in case of hardware/software failure. It implements a hot-standby system: a primary server runs by keeping a secondary server in standby mode while the primary server runs the application while the secondary server stays in a standby mode. In the event of primary server unavailability/scheduled downtime, the secondary server takes over the primary server functions.

NOTE: Currently, Failover Service is supported only for servers running on Windows Operating System. 

You can launch FOS mode from Admin > General Settings > HA Configuration.

Role Required: SDAdmin

This guide discusses configuring Failover Service through the following topics:

• Prerequisites
• How does Failover Service work?
• Benefits of launching ServiceDesk Plus MSP in FOS mode
• Set Up Process
• Set Folder Permissions
• Configuring Failover Service
• Upgrade/Restore FOS
• Disable FOS
• History

Prerequisites 

Server Requirements   

• Two 64-bit server machines with high network connectivity.
• ServiceDesk Plus MSP 64 bit .exe installations (preferred).
• Servers used for the FOS setup must have two way read-write access for the ManageEngine folder (where ServiceDesk Plus MSP is installed).
• A common IP Address in the same network as primary and secondary servers.
• Two virtual or physical servers with different NIC card addresses to set up the FOS.

ServiceDesk Plus MSP Configuration Requirements 

• FOS license must be purchased as an add-on to your application edition. You cannot view FOS configurations in Admin without applying FOS license to your application.
• The database must be externalized from primary and secondary servers but remain accessible to both. Preferably, use MSSQL setup.
• File attachment path must be set as network path by externalizing from the primary and secondary servers. The attachment path must belong to the same network domain and remain accessible to both machines.
• HTTPS certificate must be obtained for the alias URL of the common IP.
• The common URL (for which the SSL certificate is obtained) must be bound to the common IP address configured in the DNS of the network.
• The application must be started as a service using Java Service Wrapper. 
• Polling and retry parameters should be the same in both servers.
• The applications installed in the primary and secondary servers must both run on the same port.

How does Failover Service work?  

1. The Failover Service setup involves the following components:
   • Primary Server: The server where the application is currently hosted.
   • Secondary Server: The backup server in standby mode that monitors the health of the primary server periodically. The secondary server also replicates files from the primary server constantly.
   • Database Server: The primary and secondary servers are connected to a common database server. By default, the database server is used to monitor the primary server's health via the DB heart beat mechanism. The database server also replicates the data stored in the primary server. This ensures that no data is lost during the time between the server failure and the take-over.
     Note: The primary server, secondary server, and the database server are connected to a common network.
2. The IP address of the primary server, secondary server, and virtual IP should be static and in the same network.
3. The primary server's status can be monitored in two ways:
   • DB heartbeat Mechanism - Default method for monitoring the health of a peer machine. The primary server updates its status to the database server every minute. If no status update is received, it is assumed that the primary server is unavailable and the secondary server takes over.
   • Ping Mechanism - Requires SSL certificate and can be configured only in the HTTPS protocol. In case of database failure, the application automatically sets up this method.
4. Standby server monitors the health of primary via the database server and replicates files from the primary server periodically.
5. When the primary server goes down, no status update is sent to the database server. The primary server status is updated as "Down" in database server.
6. The secondary server recognises the primary server failure and instantly begins the takeover process.
7. The secondary server pulls the latest files from the primary server and takes over as the primary server. The time taken to complete the takeover depends on the size of replication data.
8. When the primary server is restored back online, it starts as the standby server and the other server continues to act as the primary server. Thus, the cycle continues.

An easier approach using Robocopy. Install the application in the primary server and execute the following command from <ServiceDeskPlusMSP_home>\bin directory: mirrorSetup.bat <IP address of secondary server>.

Use the pointers below to configure the application in FOS mode:

Primary Server Details:

• Primary Server IP - Enter the IP address of the server where the application is running.
• NIC of Primary Server - Enter the Network Interface Card (NIC) address (also called the physical address) of your primary server. The NIC address should be enclosed within curly braces { }. For example: {117C3D5B-4395-4369-8812-741EEA26D76D}.

Learn how to identify the NIC address of your primary server ServiceDesk Plus MSP contains an inbuilt provision to help you identify your NIC address.  Go to <ServiceDeskPlus-MSP>\bin directory in your primary server. Execute the iflist.exe tool. Locate the NIC Card whose Adapter Status is UP. The adapter name is the NIC address for the IP address to which the application is bound. Copy the value in the Adapter Name field to the application.

• Subnet Mask of Primary Server - Enter the subnet mask of your primary server. The default subnet mask is set at 255.255.255.0. You can also configure other valid subnet mask values.

Valid Subnet Mask values /30 255.255.255.252 /29 255.255.255.248 /28 255.255.255.240 /27 255.255.255.224 /26 255.255.255.192 /25 255.255.255.128 /24 255.255.255.0 /23 255.255.254.0 /22 255.255.252.0 /21 255.255.248.0 /20 255.255.240.0 /19 255.255.224.0 /18 255.255.192.0 /17 255.255.128.0 /16 255.255.0.0

Secondary Machine Details:

• Secondary Server IP - Enter the IP address of your standby server.
• NIC of Secondary Server - Enter the Network Interface Card (NIC) address (also called the physical address) of your secondary server. The NIC address should be enclosed within curly braces { }. For example: {03C0161D-737E-4E97-A6BA-F8546FD2C6DB}.

 

Learn how to identify the NIC address of your secondary server ServiceDesk Plus MSP contains an inbuilt provision to help you identify your NIC address.  Go to <ServiceDeskPlus-MSP>\bin directory in your secondary server. Execute the iflist.exe tool. Locate the NIC Card whose Adapter Status is UP. The adapter name is the NIC address for the IP address to which the application is bound. Copy the value in the Adapter Name field to the application.

• Subnet Mask Secondary Server - Enter the subnet mask of your secondary server. The default subnet mask is set at 255.255.255.0. You can also configure other valid subnet mask values. 

• Virtual IP - Specify the IP address to which the primary and secondary server must be bound to. You can access the application by using a virtual IP address. Ensure that the virtual IP address you configure belongs to the subnet mask and is not bound to any existing servers in the network.

• Common Alias Name - Specify a domain name using which you can access the application apart from the virtual IP address. You can customize the alias name as needed.
• In case of failover notify to - Specify the email address to which notifications must be sent in the event of a server failure. Notifications regarding failover service monitoring alerts, data synchronization alerts, and secondary server takeover alerts are built-in and will be sent to this email address. You can configure multiple email addresses by separating them using commas.

 

By default, the primary server monitors the secondary server's status every 5 minutes. In the event of secondary server failure, an email is triggered to the configured email address. You can modify the primary server's listening time as needed by following the steps below:

1. Navigate to {SDPMSP_home} / conf.
2. Open the ha.conf file and find the entry: #peer.status.check.time.period=
3. Uncomment the entry by removing the hashtag
4. Specify the required time period in minutes. For example: peer.status.check.time.period=10

For the notification emails to be sent, the outgoing mail server should be configured for the application. You can customize the notification message from Translations. 

Click Save and restart the application for the configurations to take effect.

NOTE:

• After setting up FOS configuration, set up HA file replication configuration.   
• When the secondary server takes over as the primary server, the configurations in the FOS page are NOT auto-updated accordingly. In other words, FOS configurations do not reflect which server is primary/secondary unless manually updated. 
• While editing FOS configurations or general configurations like changing the webserver port, theme changes, or translations, always update the primary server first.

Upgrade/Restore  

Upgrade FOS

To upgrade your application,

1. Invoke <ServiceDeskPlus-MSP>\bin\shutdown.bat in the primary and secondary server. This will stop ServiceDesk Plus MSP.
2. Upgrade the build in the primary server using PPM. Click here to learn how.
3. Mirror the settings in the secondary server via Robocopy by invoking <ServiceDesk Plus MSP HOME>\bin\mirrorSetup.bat <IP address of secondary server> - pass the secondary server IP as parameter.
4. Invoke <ServiceDeskPlus-MSP>\bin\run.bat in both the servers to start ServiceDesk Plus MSP.

NOTE: Ensure that you backup your files before upgrading your application. Click here to know more.

Disable FOS 

To disable FOS from the application,

1. Uncheck the Enable FOS Startup Mode option under Admin > General Settings > HA Configuration.
2. Invoke <ServiceDeskPlus-MSP>\bin\shutdown.bat in both the primary and secondary servers. This will stop ServiceDesk Plus MSP.

You can then restart the application in the servers individually by invoking <ServiceDeskPlus-MSP>\bin\run.bat command. On restart, the servers will behave individually as two separate machines.

Alternatively, you can also start ServiceDesk Plus MSP as a service.

History 

The history tab documents the summary of operations performed on HA Configuration.