Before you begin the process of migrating to WebSphere® Application Server Version 8.5, there are some considerations
of which you need to be aware.
Supported configurations: This
article is about configuration migration, such as migrating deployment
managers and federated nodes in a network deployment environment.
The Application Migration Toolkit for WebSphere Application Server
provides support for migrating applications from previous versions
of WebSphere Application Server to the latest product version. For
information about migrating applications, read more about the Application
Migration Toolkit.
sptcfg
Considerations for AIX®, HP-UX, IBM i, Linux, Solaris, and Windows operating systems
Consider the following information
before you migrate Application Server:
- Before you perform the migration, evaluate the items deprecated
in WebSphere Application Server Version 8.5.
For more information,
see Deprecated, stabilized, superseded, and removed features.
- Before you migrate to Java Standard Edition (SE) Development Kit (JDK) 6 from JDK 5 or JDK
1.4 , review your applications for necessary changes based on the Java specification. IBM® WebSphere SDK Java Technology Edition
Version 6.0 is installed by default with WebSphere Application Server Version 8.5. Optionally, you
can use the Installation Manager to install IBM WebSphere SDK Java Technology Edition
Version 7.0.
Avoid trouble: Do not enable SDK Java Technology Edition Version 7.0 unless all
nodes are migrated to
Version 8.5.
gotcha
See Migrating API and specifications for more information.
- The migration articles in this information center assume that WebSphere Application Server Version 8.5 is being installed
in an environment where it must coexist with previous versions of WebSphere Application Server.
Consider the
following items when planning to enable coexistence:
See Running multiple application server versions for more information.
- WebSphere Application Server Version 8.5 migration converts
HTTP transports to channel-framework web container transport chains.
For more information on
WebSphere Application Server Version 8.5 transport support,
see the following information:
- Configuring transport chains
- HTTP transport channel settings
- Transport chains
- If you create a profile that does not meet the migration requirements
such as naming requirements, you can remove the previous profile and
create a new one rather than uninstalling and reinstalling the WebSphere Application Server Version 8.5 product.
- The migration tools create a migration backup directory containing
a backup copy of the configuration from the previous version. The
following guidelines might help you to determine the amount of file-system
space that this directory might require:
- If you are migrating from Version 6.1 or above, the space available
for this directory must be at least the size of the configuration
directory and applications from the previous profile.
- If you use the migration tools to create more than one Version 8.5 target profile on
the same host or installation instance and you use the default port
settings, there is a chance that the target profiles will share the
same ports for some of the new Version 8.5 port definitions.
This will cause startup problems if both of the migrated profiles
are used.
If you are migrating two or more profiles that reside
on the same host or installation instance, perform the following actions
for each additional target profile:
- Before using the migration tools, use the Profile Management tool
or manageprofiles command to create the target
profile and make sure that you select unique ports rather than using
the default ports.
- When you use the migration tools, select the target profile rather
than letting the tools create it.
- The amount of storage that your system requires during migration
to Version 8.5 depends on
your environment as well as on the migration tool that you are using.
- WASPreUpgrade storage requirements
- Location: Backup directory specified as a parameter of
the WASPreUpgrade command
- Amount: For an estimate of your storage requirements when
using this command, add the following amounts.
Size of the following items for the previous
profile or instance that you are migrating:- profile_root/installableApps directory
- profile_root/installedApps directory
- profile_root/config directory
- profile_root/properties directory
- Shared libraries referenced in the libraries.xml configuration files
- Resource adapter archive (RAR) files referenced in the resources.xml configuration files
- If trace is enabled, which is the default, up to 200 MB (depending
on the size and complexity of your configuration)
For more information about this command, see WASPreUpgrade command.
- WASPostUpgrade storage requirements
- For an estimate of your storage requirements when using this command,
add the following amounts.
For more information about this command, see WASPostUpgrade command.
- If you use isolated data repositories—specifically, nonshared
data repositories such as transaction logs for SIB and Apache Derby
databases—and you migrate from a previous release, your existing databases
and transaction logs are saved when the WASPreUpgrade command is run. Any database changes that you make after you run
the WASPreUpgrade command are not reflected in
the migrated environment.
- If you have mission-critical information that is stored in these
local data repositories, you should safely shut down all servers that
interact with those repositories before attempting migration. Those
servers should remain offline until the migration has been successfully
completed or rolled back.
- If you make multiple attempts at migration, either because of
unexpected rollback or to apply fixes, rerun the WASPreUpgrade command so that any changes to your isolated data repositories are
reflected in the migrated environment.
After the migration is complete or you have rolled back to the
previous version, you can restart the servers that interact with these
isolated data repositories.
- Before you migrate an Apache Derby database, ensure that any application
servers hosting applications that are using the Apache Derby database
are closed. Otherwise, the Apache Derby migration fails.
- If you updated your java.security file in the previous version
of WebSphere Application
Server, ensure that your updates are located in the migrated java.security
file, which is located in V85WAS_HOME/java/jre/lib/security/java.security.
- The process for disabling credential prompting has changed.
To disable credential prompting in Version 8.5, configure the ipc.client.props
to disable credential prompting before migrating from Version 6.1
to Version 8.5.
- During migration, some of your application metadata might be reset
to the default and cause the application to function differently from
what you expect.
If you installed an application in your old environment
with Use Metadata From Binaries set to true and during that
installation or a future update of the application you made a change
to the application's metadata (such as JNDI resource references or
database entries for example), the change might be lost when you migrate.
When Use Metadata From Binaries is set to true, the administrative
code only updates the metadata in the binary EAR file. This option
is not supported in a mixed cell; therefore, it is automatically turned
to false as part of migration. When this happens, the expanded metadata
in the configuration directories take precedence over the values in
the binary EAR file. This causes the values from the original EAR
file installation to take precedence over any updates that you might
have made.
Perform one of the following actions to resolve this
issue:
- Before migrating, update your applications in the old environment
and set Use Metadata From Binaries to false. Ensure that the
applications are functioning correctly with this new setting, and
then run the migration.
- After migrating, update your applications and correct the metadata
as required to allow the applications to function appropriately.
- After you use the migration tools to migrate to WebSphere Application Server Version 8.5, you might need to
perform some actions that are not done automatically by the migration
tools.
- Examine any Lightweight Third-Party
Authentication (LTPA) security settings that you might have used in WebSphere Application Server Version 6.1 or
above, and verify that Version 8.5 security is set appropriately.
See Lightweight Third
Party Authentication for more information.
- Check the WASPostUpgrade.log file in the logs directory for details about any JavaServer Pages
(JSP) objects that the migration tools did not migrate.
If Version 8.5 does not support
a level for which JSP objects are configured, the migration tools
recognize the objects in the output and log them.
- Verify the results of the automatic Apache Derby database migration,
and manually migrate any Apache Derby databases that are not automatically
migrated by the tools.
See Migrating Apache Derby databases for
more information.
- WebSphere Application Server Version 8.5 does not include
the WebSphere Connect
JDBC driver for SQL Server. The WebSphereConnectJDBCDriverConversion
tool is provided to convert data sources from the WebSphere Connect JDBC driver to the DataDirect
Connect JDBC driver or the Microsoft SQL Server JDBC driver.
See Migrating from the WebSphere Connect JDBC driver for more information.