It is also recommended that you attend a z/OS UNIX System Services concepts class and a class in using z/OS UNIX System Services prior to migrating to z/OS Communications Server. If this is not possible, then you will want to ensure that the z/OS UNIX System Services implementer and the RACF® administrator work together with you during the installation and customization process.
Planning for and installing z/OS Communications Server requires MVS™, UNIX, and networking skill. If your background is in traditional MVS programming or system programming, the z/OS UNIX System Services terminology might at first seem to be somewhat confusing. If your background is in the UNIX environment, the terms should be familiar to you.
In the past, MVS TCP/IP system programmers have needed a working knowledge of the MVS or z/OS system. These programmers have been accustomed to working closely with the RACF administrator and z/OS system programmer for authorizations; the VTAM® and NCP system programmers for SNALINK and NCP connections; the IP address administrator for basic name and address assignments; and the administrators of the router network and channel-attached peripherals for connection definition and problem determination.
With the introduction of z/OS Communications Server, the TCP/IP system programmer needs to develop an additional alliance with the z/OS UNIX System Services system programmer. The TSO interfaces that have been traditionally available in the host-based TCP/IP still stand at the system programmer's disposal and additional MVS console commands simplify some TCP/IP operations. However, another user interface provided by the UNIX shell environment, either with the z/OS shell or the ISPF SHELL, is a useful and sometimes necessary tool that the TCP/IP system programmer will need to work with. Additionally, the tight coupling of z/OS Communications Server with z/OS UNIX System Services means that the TCP/IP system programmer needs more than a passing knowledge of UNIX conventions, commands, and hierarchical file system concepts. Even if the system programmer is familiar with other UNIX environments, work with the UNIX shell requires more than basic familiarity.
In the first version of a full TCP/IP stack based on native MVS and on z/OS UNIX System Services, few have all the requisite skills to successfully implement z/OS Communications Server on their own. As more and more system programmers acquire skills in UNIX System Services and in TCP/IP, this will become less and less the case. Working with the z/OS UNIX System Services implementer when implementing z/OS Communications Server provides the most effective solution to establishing a working z/OS Communications Server environment.
If you are migrating to z/OS Communications Server, establish a migration process to move all your existing applications, and after this, consider the use of new and enhanced functions based on z/OS Communications Server: New Function Summary. z/OS Communications Server allows multiple copies of the TCP/IP protocol stack to execute on the same MVS image. However, with all the performance enhancements introduced in z/OS Communications Server, it is probably not necessary to implement a multi-stack system for production purposes unless one is considering building a system programming test stack.