Managing CS Linux client/server systems

CS Linux can operate as a standalone system with all SNA components and applications on a single Linux system, or can operate as part of a client/server domain. A client/server domain includes both servers (SNA nodes) and IBM Remote API Clients (which can access SNA connectivity through a server).

In a domain with multiple CS Linux servers, one server holds the controlling copy of the CS Linux domain configuration file. This server is known as the controller server. You can define other servers in the domain to be backup servers. The domain configuration file is copied to backup servers - either when they are started, or when the controlling copy is changed - so that all backup servers hold a copy of the latest information.

Remote API Clients can be computers running AIX, Linux, Linux for Power, Linux for IBM Z, or Microsoft Windows. Remote API Clients can also run in containers on AIX, Linux or Windows systems; this provides SNA APIs for applications that run in containers like Web Application Server using Java-for-CPI-C applications. The container must have a DNS name to help the domain servers resolve the IP address of the containers. (CS Linux server cannot be installed into a container because of kernel dependencies.)

Servers and clients communicate across the CS Linux domain using TCP/IP; both IPv4 and IPv6 addressing are supported. A client can access one or more servers at the same time, and can run concurrent applications as needed. For information about the networking requirements for a client/server configuration, see IP networking requirements.

The TCP/IP connections used between clients and servers may flow across physical LANS, WANs, or virtual paths between servers running under VM. In the CS Linux books, the term LAN is used for all of these.

For Remote API Clients on AIX or Linux, you must supply information about the CS Linux network and servers. For information about this function, and for instructions on enabling and disabling the CS Linux software on clients, see Managing Remote API Clients on AIX or Linux.

All administration commands can be issued on a server. However, there are restrictions on which commands can be issued on AIX and Linux clients.

• You can issue any query or status command on a an AIX or Linux client.
• Some other administration commands, defined in IBM Communications Server for Data Center Deployment on Linux Administration Command Reference, explicitly say that they can be issued from an IBM Remote API Client. Otherwise these commands are available only from a server.

For Windows clients, you must supply information that CS Linux can use to enable the client software. If you plan to have invokable TPs on the Windows client, you must also supply information about the TPs. For information about these functions, and for instructions on enabling and disabling the CS Linux software on a Windows client, see Managing Remote API Client on Windows.

Administration commands, defined in IBM Communications Server for Data Center Deployment on Linux Administration Command Reference, cannot be issued from a Windows client.