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At times debugging certain Oracle VM or Oracle VM Manager related issues is quite challenging. In today’s article I’d like to discuss the different log locations to better assist those in trying to solve a particular issue.

I will start off by discussing the Oracle VM Manager 2.2. The Oracle VM Manager has three main log files all located under the /var/log/ovm-manager directory. These files are the db.log, oc4j.log, and the ovm-manager.log
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When considering an Oracle RAC environment, one of the main questions that always seems to be asked is “How much is Oracle RAC licensing going to cost me?” While Oracle RAC licensing can be expensive, there is a way to cut some of those expenses out by ensuring that the amount of CPUs you are licensing is truly what you need. While attempting to size your physical environment with the correct amount of CPU cores required is possible, it is also very difficult due to vast growth of multi-cored CPUs in the market. A better option would be using Oracle VM to hard partition only the cores required for your Oracle RAC environment. This methodology known as ‘hard partitioning’ allows you to take advantage of Oracle RAC technology and save on Oracle RAC licensing costs.
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In today’s Oracle VM Manager there is no way of extending the disk size of a guest VM. However, via this tutorial I will show you how to extend the .img file.

PLEASE NOTE: It is highly recommended to make a backup of the disktoExtend.img file prior to trying the steps below.

Let us assume we have an Oracle VM guest which contains 3 files. The three files are the following: System.img, disktoExtend.img, and vm.cfg. Our guest VM is running RHEL/OEL.

[root@OVMSERVER]# ll
total 22000640
-rw-r--r-- 1 root root 26847313920 Oct 13 10:28 disktoExtend.img
-rw-r--r-- 1 root root 11630545920 Oct 13 09:57 System.img
-rw-rw-rw- 1 root root 459 Oct 13 10:27 vm.cfg

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If you haven’t checked out the latest Oracle 11gR2 ( VM template, it can be found at

Once there, under ‘Select a Product Pack’, pick Oracle VM Templates, and under ‘Platform’ pick your achitecture, 32 bit or 64 bit. Then look for the template labeled: Oracle VM Templates for Oracle RAC 11gR2 Media Pack v1 for x86 (32 bit) or Oracle VM Templates for Oracle RAC 11gR2 Media Pack v1 for x86_64

The 11gR2 templates are linked on OTN at:

However, if your looking for the 11gR2 ( Oracle VM template, it requires you have access to My Oracle Support. Only customers with support can download the under the patch number 10113572

If you want to know more about how the templates work and have access to Oracle OpenWorld on Demand, once logged in go to the search navigation bar and type ‘Oracle VM Best Practices’, once there you will find our (Saar Maoz and Roger Lopez) session presentation slide deck as well as audio to accompany the slide deck. Saar did a great job on creating these templates and it truly shows. I hope you all can check them out!

If you do not have access to download the presentation but want a copy, feel free to comment on this post so I can get you a copy.


Ever try and startup a virtual machine and got the following xc_dom_do_gunzip error?

Start - /OVS/running_pool/30_owi2
PowerOn Failed : Result - failed:failed: Error: (1, 'Internal error', 'xc_dom_do_gunzip: inflate failed (rc=-5)\n')>

File "/opt/ovs-agent-2.3/", line 57, in xen_start_vm
File "/opt/ovs-agent-2.3/", line 85, in run_cmd
raise Exception('%s => %s' % (cmdlist,>

File "/opt/ovs-agent-2.3/", line 131, in start_vm
raise e

A colleague of mine ran into this issue a few days ago, and I decided to post about what was causing the problem. At first glance, I thought it had to deal with xen memory ballooning in the OVM environment (since it mentioned the word inflate), but I was wrong. The root cause of the problem is that the root directory “/” under /dev/sda2 (default OVM storage layout) was full. Since the root directory diskspace was at capacity it wasn’t able to start up the VM.

The fix is to free up some space from your root directory in order to get rid of the problem. While the solution is an easy one, it can be tricky to see how your root directory could cause your VM not to start since all your VM files are located in the /OVS directory. For that reason, I decided to post about it anyway since the error message is not very clear on what could be causing the problem.

Hope this helps someone out and feel free to comment! 🙂

Ever had your virtual machine show an incorrect status such as ‘Shutting Down’ and just stay in that status indefinately? Well there is some good news, it’s an easy fix. There are a couple reasons this can occur. First, if you stopped your virtual machine from the OVM server instead of the OVM Manager this could cause the OVM Manager and OVM server to be out of  ‘sync’ when reporting the status of your virtual machine. In other cases, it could be a bug between the communication of the OVM Manager and Oracle VM server. In either case there are a few options in solving your issue.

In OVM Manager 2.1.*, you will need to manually update the Oracle VM Manager database status of your guest virtual machine.
Login as ‘oracle’ into your OVM Manager and follow the steps below.

$ export ORACLE_HOME='/usr/lib/oracle/xe/app/oracle/product/10.2.0/server'
$ export ORACLE_SID=XE
$ ${ORACLE_HOME}/bin/sqlplus system/oracle@XE
$ SQL> update ovs.ovs_vm_img t set t.status='Powered Off' where t.img_name like '<MY_VM_NAME>';
$ SQL> commit;
$ SQL> quit;

In Oracle VM Manager 2.2 and above, the process is quite simple. Oracle has introduced the ‘Reset’ option which will set the virtual macine guest to its correct state.
The steps are as follows:
1) Click on the Virtual Machines tab found on the top left corner.
2) Select the radio button of the appropriate virtual machine that has the incorrect status displayed.
3) Click on the ‘More Actions:’ drop down box and select the option ‘Reset’
4) Click the ‘Go’ button for the reset to take place.

Once the ‘Go’ button is selected, the virtual machine will reset and display the appropriate virtual machine status.

Hope you enjoyed this article and feel free to post any comments our questions.


In today’s topic, I’d like to discuss the process of backing up and restoring your Oracle VM Manager. Since the Oracle VM Manager is used to manage all your virtual machines and virtual machine resources, I thought it would be a good exercise to discuss the step-by-step process on backing up and restoring the OVM Manager environment. It is crucial to make backups of your Oracle VM Manager to ensure that you don’t lose any data from the Oracle VM Manager repository database that could cause you a headache in having to actively restore each virtual machine to a new Oracle VM Manager, one by one (not a fun exercise). The good news is Oracle has made the backup-restore process quite easy. In the example below, I will be backing up my original Oracle VM Manager, and restoring the content from my old server it into a new server all that has a fresh install of Oracle VM Manager.

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One of the tougher aspects of Oracle VM is deciphering how to debug errors found in the logs within the Oracle VM Manager. Today I’d like to discuss an issue I’ve come across when trying to create a server pool within the Oracle VM Manager. The bug specifically consisted of my Oracle VM Manager not correctly entering the proper IP information within the /etc/hosts file of my Oracle VM Server host.


In one of my earlier posts, I discussed setting up a shared storage repository using OCFS2. Today, I’d like to discuss the steps involved in implementing additional repositories to your Oracle VM Server. One of the main reasons you would want to add an additional repository is the simple fact of not having additional space within your current OVS repository to host more virtual machines. In this tutorial, I’ll show you step by step on how to do just that.


With the introduction of OCFS2 1.4 within Oracle VM 2.2, Oracle VM 2.2 has the ability to thin provision your files within your OCFS2 filesystem via the use of the sparse files. One might ask, what exactly is a sparse file? A sparse file is a file that attempts to use filesystem space more efficiently by effectively only using the space required to fit actual data. For example, imagine I have a System.img file within my Oracle VM repository that is 6.2GB in size as seen here:

[root@ovm]# ls -llh System.img
-rw-r--r-- 1 root root 6.2G Apr 14 09:18 System.img

If I did not have the sparse file feature within my Oracle VM 2.2 operating system, the  System.img file would actually take up 6.2GB of allocated space away from my OVS repository. However, with the introduction of sparse files to OCFS2 1.4, the actual data contained within  my System.img  was only 3.3GB as shown below. A total savings of 47% of actual diskspace!

[root@ovm]# ls -lsh System.img
3.3G -rw-r--r-- 1 root root 6.2G Apr 14 09:18 System.img

Now that we understand the huge advantages of enabling sparse files, I will show you how to enable sparse files for your Oracle VM 2.2 environment.