In this part we show how easy it is to create, activate, move, and stop a system WPAR – all using the WPAR manager (browser) console. In part one we show how to configure the WPAR manager, and in part 2 we show how to register and discover WPAR agents – or AIX 6.1 servers that will be hosting System WPAR's and/or Application WPAR's.

Although the focus is on the WPAR manager – we start with getting the WPAR hosting environment ready. In this case: setting up the NFS environment to support Live Application Mobility.

We already have the WPAR manager with agents. Additionally we will need an NFS server to support the Live Application Mobility – or move an active WPAR from one AIX host to another AIX host. In my environment I have an AIX 5.3 server with the storage I need. I have created a seperate filesystem (/backup/wpars) and created a seperate sub-directory for each planned WPAR. Further, I have added entries for each of the WPAR systems or application servers (names x150 to x159). The directory permission on the NFS server for /backup/wpars is 700 (rwx------) root:system.

As each subdirectory gets mounted seperately the permissions do not need to be so strict. Each individual WPAR is chroot() to the subdirectory with it's name (e.g. WPAR x151 will reside physically on x054:/backup/wpars/x151. However, more strict permissions will probably leave a better impression with most EDP auditors.

Here is the NFS area before anything has happened. Notice the total disk usage is 16.

With out infrastructure ready for deployment we can move our focus to WPAR Manager console at the Workload Partitions panel.

Click in the menu to get to the correct panel:

If you have been following the articles you should see something very similar to this:but before you “Click on New.” we need to do some preparation on a NFS server so that we can also use Live Application Mobility

This opens the following dialog. We are going to create system WPAR x150, hosted by AIX server x203, with the files being stored remotely to enable application mobility.

Once the form is complete and we click on OK the process starts. Creating a system WPAR takes a few minutes – from 6 to 10, and there are ways to watch it progress. The menu item you need now is:

You should get something like this:

Keep clicking on the highlighted name and you will continue to get more information abiut the current step, or as we shall see in part 4, error messages that we can use to resolve problems with the current status of a WPAR.

When the WPAR deployment is complete in the task area you will be able to see something like this:

and back at the WPAR panel you will see something like this:

What resources have been created and where?

For a system WPAR the filesystems /usr and /opt are “borrowed” from the hosting system. This is why it is very important that all hosting systems are at the same level of AIX (e.g. For /usr/lib/* - the shared libraries). In my environment I have assured the equality of the hosting systems by having installed them all from the same clone (mksysb) image.

My NFS server is a p615 running AIX 5.3. For NFS it is not important which version of AIX is running. Currently nearly everything is at it's default for NFS. As AIX 6.1 is looking more and more to NFS v4 one of my next tests will be to force the AIX 5.3 server into NFS v4 for this export.

So, taking a quick peek at what is now available after the deployment (creation) of a system WPAR I have excuted du -s for an estimate of the storage requirements, and an ls -l for a look at what has been made. The sizes are low compared to a seperate system – remember /usr and /opt are coming from the hosting system. The rest, however, looks pretty standard AIX – which is as it should be.

With everything in place, it is simple to start our new virtual system – x150. Proceed to WPAR Manager and select the action/task – Start!

This updates the panel to show the system is Transitional and can be monitored in the Task Panel.

However, starting an image does not take long – there is no hardware POST (power on self test) so let's just login. The image has ssh installed, so we connect using a ssh client.

and

Once we complete the login we have a regular terminal session. My first test is to start topas and I see I may need to do some changes to get the screen colors right.

However, I am much more interested in Live Application Mobility.

Live Application Mobility

In this example I am going to use the WPAR Manager to do all the work around managing the process of moving a system WPAR from one host (currently on x203, an LPAR on a Power5 Model 51a, to x103 – a similar LPAR on a similar, but different! Power5 Model 51a. So, together with the NFS server, my physical configuration is two Power5 systems and one Power4.

Using WPAR Mananger is very simple – but I want to be able to monitor the lag the System WPAR experiences, so I start a simple loop that will give me the date every 15 seconds. I could have made this loop shorter to get a closer estimate of the time the virtual system is paused, but I did not want too much text on my screen either.

With this demo program running I switch my focus to the WPAR Manager panal again, and select “Relocate”.

The WPAR manager comes with a suggestion of a best system to go to, and as it is on the other P5 system I just use the suggested system, rather than browsing for another candidate.

In the Application Tasks I can monitor the progress....

or, I can go to the system and watch my program as it progresses. Remember, this is a TCP connection (ssh) from a PC to a “remote” system. I do not want to have to restart my client when the system comes up again!

Not being really exciting to watch I decide to take a peek at the Task Application (screen above) and click on the “Relocate Workload Partition” task in progress to see what I might see.

I see here that the system has completed the checkpoint and is in the process of restarting the system on the new server x103. After a short wait I see the screen start filling with new entries and the system WPAR has been relocated.

And with that knowledge I went back to my ssh session to see if I was still alive. As you can see, there is a pause – compareable to the times in the screen shot above. I highlighted the times – and then got distracted.

What about WPAR Pause?

WPAR Pause – I saw it in the task view – and I recalled seeing it in the WPAR Managed Systems Panel. And, having a long memory I recalled that WPAR Pause was only supported on Application WPAR's – during the beta test it seems. Because Pause is fully supported now.

And at the System WPAR....

Stopping a WPAR 

Using WPAR Manager I shall stop the System WPAR – but note this is not the suggested way to stop a system WPAR. It is much better to run the AIX shutdown command from within the WPAR. In part 4 I'll show one of the reasons why. Another reason is here: the client just ends – and no clue why!

Next Installment

Will be coming as soon as possible – and shall cover tracking errors via the Application Task Panel.