This blog contains experience gained over the years of implementing (and de-implementing) large scale IT applications/software.

Virtualisation Conundrum

Whilst researching ideas for using my VMware ESXi test rig, I came across this blog site:
I’ve added it to my Fav’s as a *must read* once in a while.
It’s packed with some very interesting articles concerning Linux, Virtualisation and more importantly, Oracle.

It may have changed my mind about using Oracle Enterprise Linux.  I’m considering shifting up the Linux tree to RedHat, or experimenting with Fedora.

See the Wikipedia tree diagram on the right of the Wikipedia Linux Distro page.

Clone a VMware ESXi Virtual Machine from the Command Line

My version of VMware vSphere is obviously not the full “knock your socks off” version and prevents me from right clicking and cloning an existing VM.
Not to be downhearted, there is another way…

– VMware vSpehere client.
– Access to the VMware ESXi server console & keyboard or an SSH client (like PUTTY for Windows).
– The VMware ESXi root user’s password.

– Create the new VM using vSphere client.
– Give it a very small hard disk.
– Remove the hard disk from the VM once created.

– Enable local tech support mode from VMware *console* screen, press ALT+F1 and log in as “unsupported” with the root password.
– Enable remote tech support mode from VMware *console* screen, then use an SSH client to log into the server as root.

– Once you have a command line, locate the source virtual machine’s datastore directory under /vmfs/volumes/<datastorename>:
# cd /vmfs/volumes/ds1/source_vm

– Change to the new target VM datastore directory:
# cd /vmfs/volumes/ds1/target_vm

– Now use vmkfstools to clone the disk (note the use of thin-provisioning, you don’t have to):
# vmkfstools -i "/vmfs/volumes/ds1/source_vm/source_file.vmdk" "/vmfs/volumes/ds1/target_vm/target_file.vmdk" -d thin

– Back in the vSphere client, add the new disk to the target virtual machine and boot it.

– Bob is your uncle.

VMWare ESXi 4.1 Test Rig – UPDATE

This is an update to my previous post here.

The VMware install onto the HP XW6200 hardware was a snip:
VMware ESXi 4.1 Update 1 Install Guide
VMware ESXi 4.1 Update 1 Release Notes

I decided to use a spare 8GB USB pen (check requirements in the installation guide relating to swap space) to install the VMware hypervisor on.  This enables me to use the entire size of the internal SATA disks as VMware datastores for hosting guest operating systems.  It also means I can create a backup copy of the USB pen when trying out a VMware upgrade.

Total time to install:
– Download boot CD ISO      = 10mins.
– Burn boot CD from ISO      = 5 mins.
– Install from CD to USB pen = 10 mins.
– Download vSphere Client    = 5 mins.
                                TOTAL = 30mins.

Once installed, I then downloaded the VMware standalone converter to my laptop.
I had two VirtualBox guest machines on my laptop, so I used the VMware converter to simply pull them off (there is no pun here!) onto the VMware virtual infrastructure.
My LAN is not the fastest so total time to v2v conversion was about 10 hours to do both guest VMs.

The next problem was the Oracle Linux 6.1 install.
This seems to come in two separate parts; the boot ISO and the main DVD ISO.
Downloading the main DVD ISO took about 3 hours over my simple ADSL connection.

Once downloaded, my problems started.
I attached the Oracle Linux 6.1 boot ISO to the virtual CDROM of a new 64bit virtual machine and click “Power On”.
Then, bam!    No longmode enabled:

Well, it turns out that the history of the Intel XEON processor is a rather tarnished story of rivalry between Intel and AMD.
Although the XEON processor I have *is* 64bit capable, and does support EM64t with Hyperthreading and all that, it just doesn’t have the VT (virtualization) capability.
The spec of the XEON processors in the HP XW6200 workstations can be seen on the Intel page here

Looking at the Intel page is even more confusing, since it states it doesn’t have Hyperthreading, but I have just enabled it in the BIOS.  Does it?  Doesn’t it?    Arghh!

In summary, you’re better off getting any one of the Core2Duo processors as these will undoubtedly support EM64t and VT.
Only problem is, most don’t support 8GB of RAM due to the system board limitations (more than likely a soft limitation).  Oh dear indeed.

So my story doesn’t end there, I’m now in the process of downloading and installing 32bit Oracle Linux 6.1.  Not quite what I wanted, but it will suffice because I have limited memory so will not be needing the use of 64bit memory addressing capabilities – yet.
My other task is to download the 32bit version of the Oracle 11g XE.  But wait, Oracle only provide a Linux version of the 11g XE in 64bit mode.  Scuppered!  I’ll have to use the 32bit version for Windows only.

As you can see, we are in this awkward transition period where software is both 32bit and 64bit but hardware is 32bit or 64bit or 64bit with flags.
We are trying our best to virtualise, but for the small guy it’s an expensive project.
You either buy a server or you buy the latest and greatest desktops that support more than 4GB of RAM.
It’s a very tricky thing to get right.
For me, it’s a case of trying to keep skills current.  I think I can afford £166 for now, then re-invest another £166 at a later stage to make the jump to a “proper” 64bit (with VT) capable system.

One other thing, once the free version of VMware ESXi expires (you get 60-days free use of all the features), you’ll need to spend some time faffing with the license to register it (downgrade to free only features) so you can continue to use it. I did this up-front so I don’t have a situation where I can’t use the VMs because I forgot the expiry date.
See instructions here:

VMWare ESXi 4.1 Test Rig – Up up and away!

This weekend I will be focussing my attention on getting my new (old) HP XW6200 workstation transformed into a VMWare ESXi 4.1 test rig.
Bought on eBay for £166.00.

I did take a brief look at the Oracle VM 2.2 offering, but it required about twice the amount of storage space to install it compared to the ~200MB required by VMWare ESXi 4.1 and it didn’t have the nice GUI for simplicity or the excellent VMWare converter for transfering my existing VirtualBox guest VMs to the virtual infrastructure.

The plan is to install VMWare onto a USB pen device, then use the 500GB SATA disk and 1TB SATA disk as virtual disk storage where I can host all manner of Virtual Servers.
I’m planning to use OpenFiler inside a virtual appliance, to provide a shared chunk of disk via iSCSI so that I can get ASM working in a cluster.
I’m hoping to get an Oracle Unbreakable Linux server running and download the beta Oracle 11gR2 XE RDBMS.
For those of you in the know, Oracle don’t officially support VMWare (I wonder why…) but since I’m not running a production database, this is not a problem.  I know for sure that it *will* work fine.

The XW6200 machine spec:
2 x Intel Xeon 3.4gGhz with HT and EM64t.
256MB graphics card.
4GB RAM (for the moment, but will support 8GB via 4x2GB DIMMS).
Floppy (really!)
USB sockets galore.

It’s a little power sucker, but it supports wake-on-lan so I can have it shutdown until required.