If your applications require workload balance, and high availability,
and you want the ability to easily add new systems to meet demand as your
workload grows, you might want to migrate your Application Server runtime
and associated application servers from a monoplex to a sysplex configuration.
Before you begin
After you install the server runtime and associated business application
servers on a monoplex, you should evaluate whether you want to migrate the
server runtime and associated application servers to a sysplex configuration.
If you decide to set up a sysplex environment that consists of several z/OS
images and workload management (WLM), you must run the BBOWWPFA job in the
z/OS image on which you are starting WebSphere Application Server.
The
BBOWWPFA job is one of the jobs that are automatically generated when you
initially configure and customization WebSphere Application Server. You run
this batch of jobs to set up your z/OS environment. Typically these JCL jobs
are executed one by one in the first z/OS image that is available on the sysplex.
However, the BBOWWPFA job, which sets up the runtime (configuration) file
system for the product must run in the same z/OS image as where you plan to
start the product. To ensure that the BBOWWPFA job runs in the proper image,
add the following JCL statement, after the BBOWWPFA job statement, within
the batch of automatically generated JCL statements, before you run the BBOWWPFA
job.
/*JOBPARM SYSAFF=sxx
where sxx is
the name of z/OS image in which you are going to run the product.
About this task
A sysplex environment enables you to:
- Balance the workload across multiple systems, thus providing better performance
management for your applications.
- Add new systems to meet demand as your workload grows. This capability
provides a scalable solution to your processing needs.
- Replicate the runtime and associated business application servers. This
capability ensures that if a failure occurs on one system, other systems are
available to handle user requests.
- Upgrade the Application Server from one release or service level to another
without interrupting service to your users.
Perform the following tasks to setup the Application Server in
a sysplex configuration.
Procedure
- Set up a sysplex environment if one is not already available.
The z/OS publication z/OS MVS Setting Up a Sysplex describes
how to set up a z/OS sysplex. The directory you set up should be similar to
the following directory structure:
Figure 1. Directory structure for
two Application Servers running in a Sysplex
- Configure the Server runtime for a sysplex environment.
- Decide whether you want a single-system view of the error log.
If you want a single-system view of the error log, and initially you
set up the error log in the system logger and used DASD for logging, you must
now configure the error log in the coupling facility.
- Decide how you will share application executables in the cell.
- Set up ARM. This release does not support cross-system
restart, so you must set up your ARM policy accordingly. Make sure you specify
TARGET_SYSTEM for the system on which each element runs (if you take the default
TARGET_SYSTEM=*, you get cross-system restart).
- Decide whether you will run all the WebSphere Application Server
for z/OS run-time servers on every system in the cell.
Recommendations:
The following table provides recommendations and requirements for running
servers in a cell.
Table 1. Running
servers in a cell
Server |
Recommendations
and requirements for running servers in a cell |
location
service daemon and node agent |
- You must run both the location service daemon and the node agent on each
system in the sysplex in which you want the server runtime to run. If the
server runtime is not installed on some of the systems in your sysplex, you
do not have to run a location service daemon and node agent on those systems.
- If a server indicates that PassTickets are desirable for interaction with
a client, you must run the location service daemon and node agent on the system
where the z/OS client resides.
|
deployment
manager |
Make
sure you follow the correct steps to configure a deployment manager cell. |
- Prepare your security system.
- Set up data sharing. Refer to the DB2 Data Sharing:
Planning and Administration publication for the version of DB2 that
is running on your z/OS system.
- Customize z/OS functions on the other systems in the sysplex to
match the customization you performed as part of the initial server runtime
installation.
Complete customization information for additional
systems is contained in the generated customization instructions.
- Change the TCP/IP settings. Each system in a sysplex
contains a location service daemon, node agent, and business application servers.
The location service daemon acts as a location service agent and accepts locate
requests with object keys in the requests. Therefore it is important that
the TCP/IP domain name server (DNS) entries, and TCP/IP profile for each system
in the cell include the port for the location service daemon, and that port
is associated with the name of the new location service daemon server.
- Change DNS entries.
If you use a DNS implementation
that allows the use of generic IP names that dynamically resolve to like-configured
servers, you must adjust the IP names in your DNS. You must keep the generic
IP name of the location service daemon, but add a new IP name for the second
and subsequent location service daemon servers. The additional IP names enable
the DNS to direct work to other servers if a failure occurs.
- In the TCP/IP profile for each additional system in the cell,
add a port for the location service daemon, and associate that port with a
new location service daemon server name.
By default, the server
runtime uses port 5655 for the location service daemon. The server runtime
also names the first location service daemon server DAEMON01 and increments
the suffix on that name for each new location service daemon server; for example,
DAEMON02, DAEMON03, and so forth. Therefore, for the second system in the
sysplex, you must add a port and associate it with DAEMON02.
Example: 5655
TCP DAEMON02
Follow the same pattern for the third and subsequent systems in the
sysplexl.
- Define new application server clusters in the sysplex.
- Optional: Create deployment manager cells.
- Install the default application server on each node in your
sysplex.
- Install a deployment manager cell on one node in your sysplex.
- Add default server nodes to the deployment manager cell.
Results
You can take advantage of all of the benefits of running your applications
on multiple systems in a sysplex.
What to do next
Migrate your applications to the sysplex.