Ideal CentOS minimal template for Automation

Ever try to build a CentOS image for use with automation or just simply use for templates in general with VMware? I can tell you from experience it can be very frustrating to have a great VM that you thought would work for cloning but when you actually test it nothing seems to work. With that in mind I thought I would create this post. In a very verbose manner we will walk through the following steps

• Build a new vm from scratch
• Select a OS type that’s ready for customization specs
• Insert the functionality to copy and paste from the vm console
• Setup the console so no repeat characters appear while typing (vital for linux)
• Configure the vm tools
• Prep the VM for cloning

Let’s start by going to vCenter -> select your DC -> Create a new virtual machine

We are going to Create a new virtual machine

Give it a name and select the data center you wish to create it in

Choose the cluster

Choose the storage *Note – if using for automation, put it on shared storage

Select the compatibility mode *Note – you will not be able to choose any level higher than your supported vCenter/Host. It’s also important to know that if you choose 5.5 it will only be editable by the web client)

Choose the Guest OS family – Linux, and a OS version. *Note – I recommend using RHEL even though there is a Cent option. If you choose RHEL you can then use customization specs within vCenter

Go to VM Options tab -> Expand Boot Options -> Check Force Bios

Now expand Advanced -> Edit Configuration

Now we add the following 3 rows
isolation.tools.copy.disable FALSE
isolation.tools.paste.disable FALSE
keyboard.typematicMinDelay 200000

Click Finish when ready

Now power on the VM

Go to the manage and connect the iso image for CentOS

Launch Console

In the BIOS settings make sure to set CD-ROM Drive in the boot options to first

Now boot into your iso image

Media check, I typically skip but can be handy if you have any corrupt data from your iso

Installer is now running – click next

Select your language

Should be Basic Storage Device as the vmdm is what you will be installing to

Warning about wiping data, since this is a new VM should not matter

Choose a host name *Note with 6.5 the short name here is what it will use for the default Volume Group in the LVM configuration

Configure Network

Ensure that “Connect automatically” is checked

Select your timezone

Set your password for root

Choose your disk layout, I select “Use All Space” in order to build a default LVM

Are you sure…Yes write changes to disk

After some time the install will complete and give you this reboot screen

After the reboot is complete we login as root and update to the latest software components
Type yum update

As that completes you will see a summary
Type y to continue with the updates

Once that portion completes you will be prompted to continue with the RPM Key for installation purposes
Type y to continue

Once installation of the updates completes now you need to install perl so that vmware tools can load properly
Type yum install perl

Again a summary will appear
Type y to continue

Install the piece for automation tools to detect information about the system
Type yum install dmi_decode

Next let’s initiate the vmware tools install

Mount the disk

Now we go through the step by step commands *Note the [TAB] references the tab button as it will complete the file name or directory for you
Type mkdir /mnt/cdrom (this creates the directory)
Type mount /dev/cdrom /mnt/cdrom (this mounts the cdrom into that created directory)
Type cp /mnt/cdrom/VMwareTools[TAB] /tmp (this will copy the file to the /tmp directory)
Type umount /mnt/cdrom (unmounts the cdrom)
Type cd /tmp (takes you into the /tmp directory)
Type ls (verify file is there)
Type tar -xzvf VMware[TAB] (this will extract the files)

Next we run the following commands to kick off the install of tools
Type cd vmware-tools-distrib
Type ./vmwareinstall.pl
Choose all the defaults during installation

Once complete you will see the following on the screen

Now that we have complete the installation of tools we have a number of steps that need to occur to make this streamlined for cloning
Type rm /etc/dev/rules.d/70-persistent-net.rules
Type y
Type vi /etc/sysconfig/network-scripts/ifcfg-eth0

Move the cursor to the UUID row and type dd to delete it
Do the same for the HWADDR

Type :wq in to save and exit the editor

Now lets disable the firewalls that would prevent communication of any agents
Type chkconfig iptables off
Type chkconfig ip6tables off
Type echo 0 >selinux/enforce
Type vi /etc/selinux/config

Type i to insert
Change the SELINUX= to disabled
Type :wq to save

Your template is now ready for use!
Type shutdown -h now

Now back to the vSphere client and either take a snapshot for linked clone or clone directly to a template