Easy and Affordable Server Virtualization for SMBs
Hello.
This is Pantelis Panayiotou, Compustride's chief computer geek, and this is a presentation of a case study for a virtual server solution.
The client in this study is a construction company with approximately 170 employees. About 25 people are housed at the company's headquarters, with 5 more at a remote warehouse facility. The rest are foremen and workers at various construction sites around the country.
The client's existing IT infrastructure consists of:
Gigabit ethernet network, with an off-the-shelf Cisco RV082 router acting as an Internet gateway
A Windows 2003 machine that acts as a file server, and also doubles as an Oracle database server for the ERP software used by the client
A second Windows 2003 machine that acts as a remote desktop server for employees at the warehouse and the construction sites
The client needed to replace the RV082 router with a software-based solution that would provide better Internet usage monitoring and security. They also needed to move the Oracle database to a dedicated server for better efficiency and manageability, and to install in-house mail server software.
After careful study of the client's needs, Compustride proposed a virtual server solution that we believe is both affordable and leaves unlimited room for future expansion.
The virtual server solution in action
The hardware platform we chose is the HP DL 180 G6 server. This is an excellent machine that supports up to 12 CPU cores, 192 GB RAM, and 14 hard disk drives, 8 of which can be hot-swappable. The one sold to the client came with a 4-core Xeon CPU, 12 GB RAM, and a 1 TB RAID-1 array of two hard drives.
For the host operating system, we chose CentOS 5.5, an opensource product that is derived from Red Hat Enterprise Linux. Our experience has shown CentOS to be an extremely robust and stable platform that is also well-supported by an extensive open source community.
The host OS was configured with LVM – the Linux Logical Volume Manager – a technology that provides a unified disk space that can grow in the future on demand, together with the client's needs. LVM supports virtually all types of storage devices, including single hard drives, hard drive arrays, external storage arrays, and network shares. Any such device can be attached to the server at run-time, to automatically increase its storage capacity, without hassles such as drive letters, mount points, or data migration procedures.
For virtualization, we selected KVM – the Linux Kernel Virtual Machine – because we believe it offers better performance and flexibility when compared to competing products, such as Xen and VmWare. KVM also offers advanced high availability features, including support for live guest migration..
The server is currently configured with 3 Windows Server 2003 guests:
Guest #1 runs Active Directory and will act as a file server. It's configured with 2 GB of RAM, and is allowed to use up to 550 GB of storage space (although this can grow in the future, depending on the client's needs).
Guest #2 will be used as an Oracle database server. Because of Oracle's hefty requirements, it has been allowed to use up to 4 GB of RAM, as well as 40 GB of storage space.
Guest #3 will provide remote desktop access using Windows Terminal Services. It has been configured with 2 GB of RAM and is allowed to use up to 40 GB of storage space.
A fourth virtual guest runs Smoothwall 3 and will be used as the client's new corporate firewall. It's been given 512 MB RAM and 20 GB hard drive space. Smoothwall is an extremely easy to use opensource product with many advanced features, such as:
Live bandwidth monitoring and reporting
A transparent web proxy with URL capabilities
Tools for monitoring and managing access to online chat services
Support for third party plug-ins
An attractive web-based interface
In this case, the client will be using Smoothwall's features to monitor Internet usage and to block access to unwanted web sites and services such as Windows Live chat.
The server was meticulously set up, integrated, branded, and stress-tested for several days before it was delivered to the client. The integration process necessitated the creation of several custom scripts that automate procedures such as:
Starting all guests in the correct order upon boot
Stopping all guests cleanly and in the correct order upon shutdown
Backing up guest server files to portable USB disks
The scripts were written in Python and Bash and are highly configurable; for instance, each guest can be configured with its own custom backup sets, startup, and shutdown parameters. They normally run in the background, as system services and cron jobs. However, the end user retains has the ability to run them manually via the command-line or a the GUI.
To recap:
This is a solution that has simplified our client's data centre and has reduced their hardware and power costs by 80%. It will also allow them to expand their IT infrastructure in the future without any technical limitations. Additional services will simply be satisfied by adding more virtual guests, and additional load will be dealt with by adding hardware components, such as hard drive arrays, RAM modules, or CPUs, to the server. Most importantly, the client will be able to do this with very little downtime. The solution is also ready for high availability: the client will be able to upgrade their data centre to a 99.997% uptime one by simply purchasing a second DL 180 server and letting us work on it for a few hours.
Thank you for your time.
Update:
We are so happy with this solution, we have turned into one of our main products. C-VPS is now available for purchase.
