In addition to the differences between root installations
and non-root installations, there are several limitations on non-root
installations. This topic discusses the limitations to help you decide
if you want to use a non-root installation.
- Product limitations
- Some DB2® database products
are not supported in non-root installations:
- DB2 Net Search
Extender
- Locally installed DB2 Information
Center
Note: The locally installed DB2 Information Center is not supported
in non-root installations because it requires root user authority
to start the daemon. However, a non-root-installation DB2 instance can be configured to use a locally
installed DB2 Information
Center if it is installed on the same computer.
- Features and tools limitations
- The following features and tools are not available in non-root
installations:
- The DB2 Administration Server
(DAS) and its associated commands: dascrt, dasdrop,
daslist, dasmigr, and dasupdt
- The ability for the db2governor to increase
priority is not supported
- Automatic starting of non-root DB2 instances
at system reboot is not supported
- Health monitor limitations
- The following health monitor features are not supported in non-root
installations:
- Running script or task actions on alert occurrences
- Sending alert notifications
- Partitioned database limitation
- Only single-partition
databases are supported in non-root installations. You cannot add
additional database partitions.
- Listing DB2 database products
- The output produced by the db2ls command, when
run as a non-root user, is different than the output produced when
run as a root user. For details, refer to the db2ls command
topic.
- DB2 copies
- Each non-root user can have only one copy of a DB2 database product installed.
- DB2 instance limitation
- In non-root installations, one DB2 instance
is created during installation. Additional instances cannot be created.
- DB2 instance actions can
be performed only by the instance owner
- Root installations and non-root installations can coexist on the
same computer in different installation paths. However, a non-root
instance can be updated, or dropped (using the db2_deinstall command),
only by the non-root user who owns the non-root instance.
A DB2 instance created by a user with
root user authority can be updated or dropped only by a user with
root user authority.
- Upgrading limitation
- Root instances cannot be upgraded to a non-root instance.
- Manual kernel parameter updates required
- Automatic Linux kernel parameter modification is not supported
for non-root installations. Kernel parameters in non-root installations
must be updated manually as described in the "Modifying Kernel Parameters
(Linux)" topic.
- Post-installation actions can be performed only by the DB2 instance owner
- Root
installations and non-root installations can coexist on the same computer.
However, only the original non-root user who installed the DB2 database product can perform
subsequent actions such as:
- Applying fix packs
- Adding features
- Installing add-on products
- Adjusting ulimit values
- The ulimit command on UNIX and Linux operating
systems sets or reports user resource limits, such as data and stack
limits. For root instances, the database server dynamically updates
required ulimit settings without changing the permanent settings.
However, for non-root instances, the ulimit settings can only be checked
during installation. A warning message is displayed if the settings
are inadequate. Root user authority is required to change the ulimit
settings.
Limitations that can be overcome by running db2rfe
There
are further limitations on non-root installations which can be overcome
by running the
db2rfe command. The following features
and abilities are initially unavailable in non-root installations:
- Operating system-based authentication
- High Availability (HA) feature
- The ability to reserve service names in the /etc/services file
- The ability to increase user data limits (ulimits). This ability
applies only to AIX®. On other
operating systems, user data limits must be increased manually.
Run the Enable root features for non-root install command
(db2rfe) to enable these features and abilities.
Running the db2rfe command is optional, and must
be run by a user with root user authority.
Authentication type in non-root installations
Operating
system-based authentication is the default authentication type for DB2 database products. Since non-root
installations do not support operating system-based authentication,
if you choose not to run the
db2rfe command after
installing your DB2 database
product as a non-root user, then you must manually set the authentication
type. You can do so by updating the following parameters in the database
manager configuration (dbm cfg) file:
- clnt_pw_plugin (Client userid-password plug-in
configuration parameter)
- group_plugin (Group plug-in configuration
parameter)
- srvcon_pw_plugin (Userid-password plug-in
for incoming connections at the server configuration parameter)