S/390 PartnerWorld for Developers, ITSO/EFS Project EFS Systems on a Linux Base: Additional Topics

Chapter 7. FLEX-ES definitions/operation 95

򐂰 You should terminate resources gracefully, with -t or -T options, instead of killing them

(with -k or Linux commands).

򐂰 A common sequence is to -T (terminate all resources), then -x (refresh with a newly

compiled resource file), and then re-IPL a S/390 operating system.

򐂰 You can -t (selectively terminate a resource) and then -x (refresh the resources file). This

will refresh only resources that are not running at that time.

򐂰 The resource manager writes log information to the /var/log/messages file (via the Linux

syslog logging facility).

򐂰 The resource manager automatically uses TCP/IP port 555 to communicate with other

elements of FLEX-ES, whether there is a single server or there are multiple servers

involved.

7.5 CLI commands

Every S/390 emulated system instance has an associated main console for FLEX-ES control

commands. This is a virtual console that is not directly connected to a real terminal. The

commands it processes are the CLI commands, some of which are described here. (CLI

means Command Line Interface.) A program named flexescli is used to communicate with

the virtual main console. flexescli works from a Linux command line, and you can start as

many flexescli instances as you like. The flexescli program sends commands to a main

console and returns the results.

In discussions we typically ignore the details of the flexescli and main console interaction

and describe operations in terms of commands to flexescli. Also, for our basic EFS

discussion, we usually assume that only a single S/390 is being emulated at any given time.

CLI commands can be entered two ways:

򐂰 You can start the flexescli program in interactive mode and then issue CLI commands

directly at the flexes prompt provided by the CLI program. All the sample startup scripts in

the redbooks do this.

򐂰 You can use ECHO to pipe a command to flexescli. In this case, it executes the

command and terminates.

The syntax for the flexescli command is:

$ flexescli IPname systemname

$ flexescli IPname systemname filename

If the flexescli program is not in the current PATH, you would need to issue the full path

name for it. The

IPname can be an IP address, a host name that is resolved by DNS, or a

local name (in /etc/hosts). The standard IPname

localhost is used to reference the local IP

loopback address. The

systemname is the name of a syscf file used to start an emulated

S/390. In our examples, this is S14A.syscf. (The syscf suffix is omitted for the flexescli

command.) The flexescli program must always be directed to a specific S/390 instance

(even if there is only one running).

An example of executing a single command through the CLI interface might be:

# echo ‘ipl a80 0a8200’ | flexescli localhost S14A

# ... -------------- | | +-- S/390 system name (S14A.syscf)

| | | +----------- local system (TCP/IP loopback)

| | +--------------------- the flexescli command

| +-------------------------- the pipe operator

+------------------------------------ CLI command to be executed