What happens when you use the INSTALL command

Most resource definitions can be installed in groups or individually, and are committed at the individual resource level. However, some SNA LU control resource definitions must be installed in groups and are committed in installable sets.

Some SNA LU control resource definitions within a CSD group are committed at the installable set level. An installable set comprises those resources, such as a CONNECTION and its associated SESSIONS, which are dependent in some way. The backout of an installable set does not cause the whole group to be backed out. The following types of resource definition are installed in installable sets:
  • CONNECTION and associated SESSIONS definitions
  • Pipeline terminals—all the terminal definitions sharing the same POOL name
If a member of an installable group fails to install, CICS® issues message DFHZC6216 identifying the member that caused the installation of the set to fail.

All other resource types are committed individually, and not in installable sets. For these resources, the effect of a partially successful group INSTALL is to leave the resources that were added in a committed state.

If resource definition overrides support is in use, resource overrides are applied to relevant resources when those resources are installed. See Overriding resource definitions.

For the installation of installable sets and for individual definition, an INSTALL may not be successful for one of two reasons:
  1. A resource definition could not be installed because it is currently in use.
  2. A system failure occurred during installation.

You can use the CEDA INSTALL command to reinstall the same group used at a cold or initial start, and the new definitions are installed successfully, even if some original definitions are in use and fail to install.