Managing Data Centers Proficiently

OpenQRM tracks data center's usage and utilization while

generating detailed reports at the same time. It provides automatic failover for

servers under its control. In fact, you can set up automatic failover from one

openQRM managing server to another, so there's no single point of failure. The

system also supports diskless servers, which lowers the cost and rates of

failure. It can manage thousands of such servers. It dynamically adjusts the

amount of allocated servers according to actual usage and provides high

availability for enterprise services and applications. OpenQRM separates running

applications from physical servers, thereby allowing flexible use of resources

and ease of management. It supports booting of servers from local disk, NAS,

iSCSI, etc.

OpenQRM comes with a number of plugins like dhcpd for a

DHCP server. It provides the required functionality of letting node's network

boot and receive IP addresses. This plugin is useful if you don't have another

DHCP server running in your network. It also has a plugin for iSCSI, which

installs iSCSI-enabled kernels for use with openQRM. These kernels let you store

filesystem images on a storage device, which supports iSCSI. It also has a

plugin for LDAP to allow user authentication in openQRM through an LDAP server

instead of the internal user/password mechanism of openQRM. It has another

useful plugin for Microsoft Windows, which lets openQRM manage Windows. Servers

perform basic functions on it such as start and stop. It also lets you create

your own Plugins. It also has the support for different partitioning

technologies such as VMWare and Xen.

OpenQRM, by default, has a status bar at the top of the

window, which displays all the information about the virtual environments,

nodes, virtual machines. The bar shows as to how many of these are active or

inactive, idle or otherwise, giving an error message. When a machine shows

error, openQRM displays an alert on this window immediately. Here, nodes are the

machines, which are booted trough openQRM image and virtual environments are

created using these nodes. In its management tools, openQRM lets you create

filter for these nodes, virtual environments and machines. By default, it

filters them into categories like running, inactive or active, or in error etc.

In openQRM, you can create and start running virtual environments comprising of nodes such as servers in your network quite easily

Using openQRM



To start using openQRM, you first need to download the software  from

the website link given above. Here you have two options, either you can download

the ISO of openQRM and boot your server with it, or you can download the RPMS or

TGZ of openQRM and install it onto your already running linux server. Before

installing the RPMS or TGZ files, you need to make sure that you are running

'mysqld' on your server. Here we are looking at how to use openQRM with its

bootable CD. Once booted, if you don't have a dhcp server running in your

network, it will ask you to enable the DHCP plugin of openQRM. Just type 'y'

and press enter, it will start DHCP server for you.

Boot the servers or workstations with PXE that you want to

manage with openQRM. They will automatically boot from the image, which is on

openQRM server. This image will register itself with openQRM. You can also add

your own image and boot these machines from that image.  You now have two

idle nodes. Now open the openQRM GUI for this, and double click the 'OpenQRM

GUI' icon on the desktop. Next, you need to log in. By default  you can

use the following:

Userid: qrm 



Password: qrm

Once you are logged in, you can change the password if you

want. To create a new virtual environment of these machines, which we just

booted with openQRM image, browse to virtual environments. In tools, click on

new virtual environment. A window will open where you name the virtual

environment. Next it will ask you to choose a kernel image. Click on the Edit

Tab. Here, by default, you will see three images. Choose qrm image and provide

the Filesystem Image. Click on the add button. By default, there will be two

images — small_iscsi and small_nfs, choose the one according to your need. Now

you need to design the node's hardware profile. For this, specify the RAM

amount, number of CPUs and CPU speed for every node. If you are not sure about

this, you can just leave it to any, letting openQRM decide those things. 

To set the policy for the virtual environment, click on the

Provisioning and Policy tab. Here you can define the minimum, maximum and the

number of nodes, which the openQRM should use during the start. You can also

define policy for the maximum load a node should take. You can also run an

external script for policies. Next, click on High Availability tab to define

whether the virtual environment should use Automatic Application Recovery (AAR)

or not. Similarly, you can also choose the support for Automatic Hardware

Failover (AHF) and the number of minimum resources openQRM should use for it.

After giving all these details, click on 'save changes'

and the virtual environment will be created. To start this virtual environment,

got to Action drop-down tab and click on 'start'. Once you start the virtual

environment, one of your nodes will reboot and will bring up a small linux

kernel shipped with openQRM live cd.

Now, to check the High Availability feature of openQRM,

unplug the network cable or just pull the power source from your first node to

simulate a failure.  In a few seconds, or as configured by you, openQRM

will detect that it has not received any heartbeats from the assigned node.

Failover will initiate causing openQRM to de-assign the node from the virtual

environment and assign the remaining idle node.  This is to show how

openQRM will automatically keep your applications running.

You can add as many nodes as you wish and set openQRM to apply one of the three pre-configured policies/scripts on them

Creating a custom boot-image



You can create a custom boot image from a remote(running) server trough the

following way. Open a command shell and run the following commands.

> //qrm/bin/qrm-boot-image

create \



-k \-b myboot-image \-y my-boot-image \


-i

where myboot-image is the name of the image,







For example:

> /usr/qrm/bin/qrm-boot-image

create \







-k 2.6.12 \-b myboot-image \-y my-boot-image \-i 198.168.3.20

Creating a custom filesystem-image



You can create a custom filestem-image from a remote (running) server and

create a storage-server on the management configuration page in the openQRM GUI.

For creating a storage server all you need to give is ip address of the remote

storage server and specify what type is it. Next open shell and run the

following:

> //qrm/bin/qrm-filesystem-image

create \







-s myserver -i \







-n : \







--storage-server

For example:

> /usr/qrm/bin/qrm-filesystem-image

create \



-s myserver \-i 192.168.3.40 \


-n 192.168.3.20:/diskimages/ \


--storage-server mynfs-server

Bottom line



As the number of servers are increasing in data centers, openQRM provides an

easy way to manage them, thereby reducing the downtime, as it can handle

failures automatically.

Swapnil Arora