PHEXPP - Maintaining connectivity during server maintenance
PHEXPP is currently configured for failover on new connections from PHEXPP1 to PHEXPP2. However, existing connections may experience a loss of connectivity if the server they are connected to becomes unavailable.
To avoid service interruptions during planned PHEXPP1 maintenance, applications should be temporarily configured to connect to PHEXPP2 first, with PHEXPP1 as the second entry, and then changed back once maintenance is complete. The following describes the connection settings which can be used to connect to PHEXPP2 first.
Because of the way your Oracle driver or application works, you may not be able to seamlessly switch between instances during maintenance. In this case, you may want to switch to prefer the server that is not being updated -- usually PHEXPP2 -- when it is convenient for you and then switch back to the standard (PHEXPP1 first) configuration after the maintenance window.
Connection information for PHEXPP2 first:
PHEXPP =
(DESCRIPTION =
(FAILOVER=on)
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = phexpp2.db.doit.wisc.edu)(PORT = 1596))
(ADDRESS = (PROTOCOL = TCP)(HOST = phexpp1.db.doit.wisc.edu)(PORT = 1596))
)
(CONNECT_DATA =
(SERVICE_NAME = phexpp.doit.wisc.edu)
)
)
Once server maintenance on PHEXPP1 is complete, your application's configuration should be reverted back to the normal settings.
Default connection settings:
PHEXPP =
(DESCRIPTION =
(FAILOVER=on)
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = phexpp1.db.doit.wisc.edu)(PORT = 1596))
(ADDRESS = (PROTOCOL = TCP)(HOST = phexpp2.db.doit.wisc.edu)(PORT = 1596))
)
(CONNECT_DATA =
(SERVICE_NAME = phexpp.doit.wisc.edu)
)
)
Please contact mstsupport@lists.wisc.edu with any questions or concerns.