Create a Custom Template for VMware Big Data Extension

The Serengeti vApp deployed for use by VMware Big Data extension comes with two VM’s. The management VM, that contains all the CHEF recipes and manifests used for automating deployments, and a Template VM, used to deploy all the nodes of a Hadoop cluster. The template VM comes with CentOS 5 as the installed OS. You can create a Hadoop Template virtual machine using a customized version of CentOS 6.x OS. This allows you to deploy an operating system with configurations specific to your IT environment. You can create a Hadoop Template virtual machine using a version of CentOS 6.x Linux customized for your IT environment in combination with a supported Hadoop distribution. This allows you to create a Hadoop Template virtual machine using your organization's preferred operating system configuration. When you provision Big Data clusters the customized CentOS operating system will be used in the virtual machines that are created from the Hadoop Template virtual machine.

PivotalHD deployments require CentOS 6, so to deploy PivotalHD you will have to create a custom tempalte. The Table below shows the supported Hadoop Distributions by VMware Big Data Extensions. If you choose to use the custom template with CentOs6, make sure you download the appropriate Hadoop versions. It is alos possible to drab and drop the appropriate template back and forth depending on the Hadoop distributions supported OS type, although obviously this is a manual proccess.

The rest of this blog shows setting up a custom CentOs 6.4 template

Using the vCenter client, create a new Virtual Machine. Select Typical and click Next
Give the Template VM a descriptive name and choose an Inventory location. Click Next
Select a location for the template vm. It should be on shared storage. Click Next
Select Linux as the guest operating systems with “Red Hat Enterprise Linux 6 (64-bit)” as the version Click Next
Use the default Adapter and connect it to the correct network. This network should be reachable by vCenter and the Serengeti Management VM. Click Next
Create a disk size of 20 gigs Click Next

Review the setting and click Finish. Once the VM creation is finished, power on the VM and open the console.
Click the CD button and navigate to your CentOS 6.x image. CentOS images can be downloaded from: http://wiki.centos.org/Download For this install we will be using CentOS version 6.4
From the splash screen select Install. We wont walk through all the steps of Installing the OS. The Template requires a basic Install so the defaults are used. We will highlight some points of interest.
There is no need to give the template a host name. Host names are assigned by Big Data extension during deployment. For IP address we will want to use DHCP. Templates deployed by BDE use either DHCP or a IP address pool to assign IP’s. During the configuration of the template we will require access to the internet. If you do not have DHCP, assign a temporary IP address. *Remember to set the address back to DHCP after configuration*. Select Basic Server for Install.
After the install completes logon to the console. Edit the network file: vi /etc/sysconfig/network-scripts/ifcfg-eth0
Change the ONBOOT to equal yes If you are using a DHCP IP address, the ifcfg-eth0 file should look like the screen shot above when configuration is complete.
Bring up the interface with this command ifup eth0
Install the wget utility. yum install wget
Change into the temp directory cd /tmp Retrieve the java installer using wget wget https://mrplus.googlecode.com/files/jdk-6u31-linux-x64.bin --no-check-certificate NOTE: By retrieving the Java installer from a google repository we can avoid the hassle of downloading it from Oracle then uploading it to the VM .
Change the attribute on the downloaded file: chmod a+x jdk-6u31-linux-x64.bin Make a directory to install java: mkdir /usr/java mkdir /usr/java/default Move the java installer to this directory: mv jdk-6u31-linux-x64.bin /usr/java/default Change into that directory: cd /usr/java/default
Install java: ./ jdk-6u31-linux-x64.bin
Next Install VMware Tools. On the console click the VM tab, select guest and Install/Upgrade VMware Tools	1)
From the command line mount the cdrom mount /dev/cdrom /media
Change directories to media cd /media
Copy the VMware tools installer to the temp directory cp VMwareTools* /tmp
Extract the VMwaretools tar file tar –zxvf VMwareTools*
Change into the vmwaretools directory and execute the installer cd /vmware-tools-distrib ./vmware-install.pl
After the installer is done change into the temp directory and download the custom scripts from the mangemnet server cd /tmp wget https://10.10.81.36/custos/custos.tar.gz --no-check-certificate Note: Replace the IP address with the IP address of your management
Extract the contents and execute the file. tar xf custos.tar.gz ./installer.sh /usr/java/default/jdk.1.6.0_31
When the install completes, add the java path to the environment echo “JAVA_HOME=/usr/java/default/jdk1.6.0_31 “ > etc/environment
Turn the firewall off service iptables off chkconfig iptables off
If you have set a temporary IP address, set it back to DHCP. Remove the 70-persistent-net.rules file and power down the template VM. rm /etc/udev/rules.d/70-persistent-net.rules NOTE: Removing this file keeps cloning jobs from changing the Ethernet interface number. This is the last command to run before turning the template off
On the vcenter client, drag and drop the new template into the vApp. Then Drag and drop the old template out of the vApp On the management server, restart the tomcat service service tomcat restart BDE will now deploy Hadoop distributions to the new CentOS 6 template. Verify that your Hadoop distributions are for CentOS 6. PivotalHD requires version 6, other distributions have seperate packages for either version 5 or 6. The default apache distro, and my previous posts, have shown version 5 deployments. For now you can run the last 2 steps per distro (drag and drop). Hopefully in the future BDE will add support for multiple templates