Monthly Archives: July 2010

VMware Knowledge base entries of interest for Oracle DBAs

One of the things I love about VMware’s support site is their knowledge base. It’s not horrific flash like My Oracle Support (aka Metalink), and it’s freely searchable without a support contract. Also very cool is there is an RSS feed of new or updated knowledge base articles. It’s good to scan in an idle moment or two each day to have an idea of what issues other people are seeing.

Because of that RSS feed, I came across three knowledge base articles I’d like to highlight here:

KB Article 1023696: Oracle 11G R2 32 bit client fails with a segmentation fault when run in a RHEL 5.4 64 bit virtual machine

In this case, sqlplus would seg fault when you try running it. The issue it turns out isn’t a VMware issue – it’s an Oracle bug when running 32-bit 11gR2 client on a 64-bit RH OS with an AMD processor. The fix is Oracle patch 8670579.

KB Article: 1023898
RedHat and CentOS virtual machine show warning messages when starting the udev daemon

This issue actually cropped up in my VMware environments awhile ago. Basically you see messages like this when your VM starts:

udevd[572]: add_to_rules: unknown key ‘SUBSYSTEMS’
udevd[572]: add_to_rules: unknown key ‘ATTRS{vendor}’
udevd[572]: add_to_rules: unknown key ‘ATTRS{model}’
udevd[572]: add_to_rules: unknown key ‘SUBSYSTEMS’
udevd[572]: add_to_rules: unknown key ‘ATTRS{vendor}’
udevd[572]: add_to_rules: unknown key ‘ATTRS{model}’

On RHEL, the fix is to do the following

vi /etc/udev/rules.d/99-vmware-scsi-udev.rule


ACTION==”add”, BUS==”scsi”, SYSFS{vendor}==”VMware, ” , SYSFS{model}==”VMware Virtual S”, RUN+=”/bin/sh -c ‘echo 180 >/sys$DEVPATH/device/timeout'”


ACTION==”add”, BUS==”scsi”, SYSFS{vendor}==”VMware ” , SYSFS{model}==”Virtual disk “, RUN+=”/bin/sh -c ‘echo 180 >/sys$DEVPATH/device/timeout'”

and then reboot the VM.

The final article I want to mention is
KB Article: 1023185 VMware Tools installation fails to start the guest operating system daemon on Red Hat Enterprise Linux 4 64-bit guests with the 32-bit glibc-common package installed

This issue relates to Oracle because 32-bit glibc-common is frequently required for Oracle DB installs. The issue occurs because VMware tools configuration is looking for the 64-bit tools (64-bit OS, generally you’d want to install the 64-bit RPMs…). The solution is to install VMware tools as normal, but before running the configuration script, to issue
ln –s /usr/lib/vmware-tools/lib64/ /lib64/
ln –s /usr/lib/vmware-tools/lib64/ /lib64/
and then run the configuration program for vmware tools

Hopefully this is helpful to other Oracle on RHEL under VMware people out there.

Oracle VM compared to VMware vSphere: Part 1

I’ve been meaning to take a serious look at Oracle VM for a few months. In fact, it was this post [Live Migration of EBS Services Using Oracle VM] (and my long-winded reply) that was a major push for me to start this blog.

The final bit of impetus to learn all about Oracle VM came a few months ago when I saw the “Oracle VM for x86 Essentials” beta exam. If passed, you earn the certification “Oracle VM for x86 Certified Implementation Specialist”. It’s a certification geared for Oracle Partners. I figured the knowledge could help me to better understand Oracle’s offering. First and foremost, I’m an Oracle Applications DBA. If Oracle’s product could allow me to better serve my clients and do my job – awesome!

So I’ve been hitting all the Oracle VM resources I could find to learn about the product. I’ll post links to a number of the excellent resources I found at the end of this post. All the links at the bottom refer to information on the currently available product (Oracle VM 2.2). While compiling all of this information, I came across [Oracle Virtualization:Making Software Easier to Deploy, Manage, and Support] – a slide deck from a recent Sydney Australia Oracle meetup. It talks about upcoming features of Oracle VM 3.0. If those features come to pass, Oracle VM will become more enticing to many organizations.

Honestly, I’ve got *tons* of things I want to write about with regards to Oracle VM — so much that I don’t know where to begin.

General Impressions
Remember that first time you went from something with a nice GUI, like Windows (Thanks Apple Microsoft!) to something a little more “nerdy” like Linux ? The GUI, if there was one, was stripped down and clunky. Many of the things you could do with a couple of mouse clicks before now require specialized commands at a command line. All of these different steps you need to do just to get things working. Well, it’s the same type of thing going from VMware vCenter to Oracle VM Manager. It’s not that the product is bad — it isn’t. The Oracle VM interface is clunky and the product doesn’t have the richness of features of VMware vSphere. Simple as that. Are those differences worth it to you? Everyone’s needs are different. Both underlying products (Oracle VM Server, VMware vSphere ESX 4.0) run Linux and Windows VMs well enough for most enterprise-level systems.

As you can read in this Gartner report on Server Virtualization Infrastructure, VMware is the clear market leader. Oracle VM, although categorized as a niche player, is the strongest of the niche players and right on the border of being listed as a challenger to VMware.

Here are a few areas where Oracle VM has an advantage over VMware:

o Certified vs. Supported

(I hate talking about this but it needs to be addressed.) Is your VMware virtualized Oracle database supported by Oracle? YES. Is it Certified? No. I went into this in detail in this [Oracle Support on VMware] blog post so I won’t do it again. Short of running Oracle RAC, which is expressly NOT supported when virtualized under VMware, the question of whether you should care about the “certified” distinction is something each company needs to answer for themselves. To me, the whole thing smacks of FUD (Fear, Uncertainty, Doubt).

o Pricing

There are two parts to pricing. First is the effect virtualizing Oracle Database will have on your Oracle database licensing. I go into this in more detail in a post on Oracle licensing under VMware. One of Oracle VM’s main selling points is that Oracle considers Oracle VM (through hardcoding the CPU binding in the vm.cfg file) a type of hard partitioning and VMware vSphere a type of soft partitioning. When using hard partitioning, Oracle only requires you to license the processors (cores) in that hard partition (aka, the processors visible to the VM). When using soft partitioning, Oracle requires you to license ALL the processors (cores) in the server, even though there may be many more processors present than allocated to the VM. It should be noted that you can do the same type of CPU binding (called CPU affinity) with VMware vSphere, but that Oracle somehow still considers this soft partitioning.

This just seems like a way for Oracle to give their Oracle VM product preferential treatment. How does the joke go… Where does the 800 lb gorilla sit? Anywhere he wants to.

The second part of pricing involves the actual Oracle VM product versus the VMware vSphere product. Oracle basically has two pricing points
o Premier Limited — Up to 2 CPU sockets, regardless of the number of cores per socket in the physical server
o Premier — unlimited CPU sockets in the server

VMware, unlike Oracle, has four product feature levels (Standard, Advanced, Enterprise and Enterprise Plus) and so a head to head comparison is a complete pain to do. The short answer is that Oracle can be significantly cheaper.. The downside of this inexpensiveness is a lack of features. Yes, VMware generally costs more than Oracle, but you’re paying for additional features. Are those features worth it to your organization? That’s for you to decide. In my organization, we are willing to pay for VMware’s features, but my organization’s needs may be different than the needs of your organization.

Does your organization have a need for VM snapshots? Mine absolutely does. Oracle VM doesn’t have it and VMware does, even when you’re using the free version of each product.

Does your VM require more than 8 CPUs? VMware has a limit of 8 CPUs for a single VM. Oracle VM’s limit is 32 CPUs for a single VM. Through tuning and software improvements, my main client has managed to reduce the number of CPUs for our Production Oracle E-Business Suite database from an unvirtualized 8 cores to 2 cores virtualized, so the difference is immaterial… but maybe your organization needs 20 cores.

Does your organization have a need to do vMotions / Live Migrations? They come included with Oracle VM, but it’s not recommended to do more than one at a time. There is an additional cost to get VMware vMotion, but VMware supports a default configuration with up to 4 simultaneous moves and allows up to 8 simultaneous moves.

Does your organization need automated SAN level replication of your VMs so they can be brought up automatically in case of disaster? VMware has that functionality with Site Recovery Manager. Oracle doesn’t have anything like it.

o Oracle VM Templates

Do you want a pre-built VM you can download with the Oracle software already installed and configured? Oracle offers downloads of pre-built environments from a basic OEL 5 Linux box all the way through to a downloadable 38GB Oracle EBS R12.1.1 system. I admit, that could be pretty cool. However, it may not be right for your company. My main client never allows consultants to have console type access to our Linux servers. I don’t think my auditors would approve of a pre-built VM for production use, even if it was pre-built by Oracle. As something for quickly throwing up a demo or dev environment, I think it’s fantastic. I hope Oracle continues to do this for more and more of their products. Oracle Enterprise Manager 10gR5 took me roughly 2 weeks to install. Discoverer 11g about a week. Secure Enterprise Search about 2 weeks. It would be great to have a pre-built test system I could reference when building my production systems.

I’ve got numerous ideas for more blog posts with regards to Oracle VM. Feedback directing me to what interests others would be great.

Part 2 coming after the I take the exam later this week. Wish me luck!

Live Migration of EBS Services with Oracle VM
Installing & Configuring OEL 5 with Database 11gR1 as a Paravirtualized Machine (PVM) on an Oracle VM Server
The underground Oracle VM Manual
Official Oracle VM Wiki home page
Oracle VM for x86 Essentials Exam 1Z0-540 Exam Topics Study Guide
Oracle VM 2.2 Documentation Library
Performing Physical to Virtual (P2V) and Virtual to Virtual (V2V) (aka VMware to Oracle) conversions Note the excellent pdf linked from the article too.
Installing, Configuring and Using Oracle VM Server for x86