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
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
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
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
In the Application Tasks I can monitor
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
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!
Will be coming as soon as possible –
and shall cover tracking errors via the Application Task Panel.