Understanding Domain Failover

Domain Failover

Domain failover ensures that PeopleSoft Integration Broker continues processing message requests and responses, even if it incurs errors or other problems on the primary domain. When failover is activated, service operation processing will switch to back up domains should Integration Broker incur any errors or problems on the primary domain. In addition, should the domain fail, you can send a system-generated email notification to individuals.

If the connection with the database is lost and the handlers are processing service operations at that time, the handlers attempt to reboot. If initialization fails, the handlers are not rebooted. If you are using failover, the failover process takes over and failover of the domain occurs.

Domain Failover Groups

You can set up domain failover groups, so that all failover takes place on specific domains. To set up failover groups, you assign a domain a failover group number. After you assign domains to a group, you then assign the failover priority for all domains within the group.

Note:

Typically using a single failover group is all that is needed.

WARNING:

Queue sets within failover groups must be identical; queue sets between failover groups must be unique.

The example of the Failover Configuration page in the Setting Up Dynamic Primary-Secondary Dispatchers section of the documentation shows four domains attached to the application server. The first two domains have been assigned to failover group one, as indicated by the value 1 in the Failover Group field for each domain. The last two domains have been assigned to failover group two, as indicated by the value 2 in the Failover Group field for each domain.

The failover priority within group one is as follows: the first domain in the list is the main and primary back-up domain as indicated by the failover priority value 1; the second domain in the list is the second back-up domain as indicated by the failover priority value 2.

The failover priority within group two is as follows: the third domain in the list is the first back-up domain for group two as indicated by the failover priority value 1; the last domain in the list is the second back-up domain as indicated by the failover priority value 2.

Failover Groups — Priority Reset

PeopleSoft Integration Broker features a priority reset option that works in conjunction with failover groups.

When you set this option and failover occurs, the system attempts to use the domain defined as group priority value of 1 before failing over to the next sequential domain.

As an example, you could have a failover group defined as follows:

Group Failover Priority	Domain Name
1	QEDMO
2	DOMAIN02
3	DOMAIN03

In the example in the table, domain QEDMO has already failed over to domain DOMAIN02. If domain DOMAIN02 subsequently fails, the system attempts to failover back to the domain with the highest failover priority setting, domain QEDMO. If the system is unsuccessful in failing over to domain QEDMO, domain DOMAIN02 fails over to the next sequential domain in the failover group, domain DOMAIN03.

You set the Priority Reset option on the Failover Configuration page.

See Enabling Failover on Domains.

Dynamic and Static Primary-Secondary Dispatchers

You can implement primary-secondary dispatchers in conjunction with domain failover.

When dynamic secondaries are implemented, the domain with the highest priority will become the active domain (primary domain) in each group during failover. The next domain in priority is automatically programmatically configured as an active secondary domain. You configure dynamic secondaries in the Service Operations Monitor.

Static domain secondaries are always secondaries. You configure static secondaries in PSADMIN.

Failover Priority — General Failover

In general domain failover, if a failover domain becomes inactive, the system attempts failover to the next in priority domain. If it is unable to do so, the next domain in priority becomes the active domain.

As an example, consider an integration system with the domains and failover priorities shown in the following table:

Domain	Failover Priority
Domain A	1
Domain B	2
Domain C	3

In this integration system if Domain A fails, the system will failover to Domain B. If Domain B later fails, the system will failover to Domain C.

Failover Priority — Dynamic Secondary Failover

In dynamic secondary failover, if the dynamic secondary fails, the system generates and email notification and the dynamic secondary becomes inactive. The system does not failover to find another dynamic secondary.

Failover on the primary system has to occur for a dynamic secondary to automatically go into effect.

Failover Priority Modification

If you modify failover priorities when failover is enabled and change the priorities of the current active domain, all domains are reset to inactive and the domain with the priority value of 1 is activated. However, if failover is not active and you change priorities, PeopleSoft Integration Broker saves the changes without any domain status reset.

Failover and Node Pause Times

Domain failover is disabled during node/system pause times. Additional information is provided elsewhere in the product documentation.

You can add scheduled pause times to nodes during which time failover does not occur. A typical case for scheduling system pause times is for scheduled or routine system maintenance. Scheduling pause times prevents failover from occurring during the defined time range and notifications from being sent when a domain is brought back up.

See Integration Broker Service Operations Monitor: Understanding Pausing Nodes.