HP-UX SNAplus2 Upgrade Guide (June 2003)

Upgrading from Earlier Versions of SNAplus2 to R6.0 and later

Phased Upgrade of a Running Client/Server System

Chapter 2 27

Restrictions in a Mixed Network of Current-Level and

Back-Level Computers

The only restrictions in support for programs on back-level computers

are as follows:

• Current-level clients cannot connect to back-level servers.

• Applications that are recompiled with current-level header ﬁles

cannot run on back-level servers or clients.

• Back-level servers cannot be administered by current-level servers or

clients. Current-level servers cannot be administered by back-level

servers or clients if new features have been conﬁgured.

• Applications on current-level servers or clients will be unable to use

resources on back-level servers.

• SNAplus2 Release 5.1 servers do notsupport Release 6.1020 systems

in a client/server system. (Refer to Table 1-2, “Client/Server

Compatibility”). If your servers are Release 5.1 and you install a new

system with Release 6.1020 software, you must do one of two things

to maintain compatibility: either upgrade all systems to Release

6.1020, or downgrade the new system to Release 5.1 (by removing

the Release 6.1020 software and then installing Release 5.1

software). If you do not have access to Release 5.1 software, contact

your HP Support Center.

Upgrade Steps

Before beginning the upgrade process, you need to determine the order

in which the servers are to be upgraded. In general, you want the master

server and backup servers in the upgraded network to be the same

servers as in the original network running the back-level software. To

achieve this, you should upgrade the master server ﬁrst, then any

backup servers in order of precedence, and then any peer servers. This

makes it easier to ensure that the servers are set up in the upgraded

network as master and backup servers in the correct order. If you intend

to use different master and backup servers in the upgraded network

from those in the original network, you should upgrade the new master

server ﬁrst, then the new backup servers in order.