TS/MP 2.5 Release Supplement

For more information on the ACS API errors, see Section 7, Pathsend Errors for ACS Subsystem in
the TS/MP 2.5 Pathsend and Server Programming Manual.
Automated Online Upgrade
The planned outage elimination feature is enhanced in the latest version of the TS/MP. It provides
capability to upgrade a server class application object online while maintaining application
consistency. When changes to the program object of a server class are made, the updated program
object can be rolled out across the Pathway domain with no loss of application, and single
application image is ensured to the Pathsend requests.
TS/MP provides a command, ALTER-DOMAIN, for an automated online upgrade. The
ALTER-DOMAIN is a non-atomic command. It issues a number of SERVER commands internally.
If there are any errors during the execution of a SERVER command, a manual recovery may be
required. The ALTER-DOMAIN command is used to upgrade servers with a newer version of the
program file. It can also be used to alter other server class attributes except SET and RESET
PROCESS.
The following operations are involved in an online upgrade of the server class:
1. When the ALTER-DOMAIN is run, the PDMCOM sends a lock message to the ACS subsystem
to lock the server such that any server command from another PDMCOM is not executed. If
the lock fails, the command is terminated.
When the ACS subsystem receives a close message (typically at the end of processing) from
PDMCOM, the locked server is unlocked.
2. After a successful lock, FREEZE and STOP server commands are issued on a single PATHMON.
This is followed by the ALTER command to change the server class attributes. After a successful
ALTER, the ACS subsystem queues all new Pathsend requests to this server class.
3. The FREEZE command is issued on all other PATHMON processes and the altered server is
thawed. The ACS subsystem starts processing new requests that are queued.
Because only the upgraded server is in THAW state and others servers are frozen, all requests
go to the upgraded server.
4. The remaining servers in other PATHMON processes are stopped, altered, thawed, and
started.
ALTER-DOMAIN is a non-atomic command. Any failure during processing must be manually
recovered.
If commands are issued from PATHCOM for the servers being upgraded when an ALTER-DOMAIN
is in progress, the results are unpredictable. You are recommended not to use PATHCOM for
operation and management of PATHMON processes, which are part of domains.
When ACS subsystem is not running:
• ALTER-DOMAIN command is rejected.
• PATHCOM process commands issued from PDMCOM are processed with a warning message.
For more information on the ALTER-DOMAIN command, see “ALTER-DOMAIN Command”
(page 40).
Synchronous Upgrade
TS/MP supports online upgrade of SCOBOL applications synchronized with online upgrade of
server class applications. This feature is useful when SCOBOL applications and the corresponding
server classes must be upgraded simultaneously.
See the synchronous upgrade in the HP NonStop Pathway/iTS System Management Manual.
TS/MP Earlier Version Features 35