Case Study: Dell SAN prepares law firm Stevens & Bolton for virtualisation

Law firm Stevens & Bolton has extended a Dell Compellent storage area network into the cloud, to take advantage of offsite business continuity.

Law firm Stevens & Bolton has extended a Dell Compellent storage area network into the cloud, to take advantage of offsite business continuity.

The law firm recently purchased a Dell Compellent replication license for its SAN, which will enable it to use cloud disaster recovery, connecting through a 20 mbps vLAN to a resilient data centre operated by IT services firm, Atlanta Technology.

The cloud project is the latest development in a refresh programme covering virtualisation, a VMware upgrade and a Windows desktop and server upgrade. The project began four years ago when David Thomas, head of IT, joined the 170 staff law firm.

Thomas was hired to implement a new IT infrastructure that took into account the long-term scalability requirements of the business. His first task was to replace an HP MSA SAN, that had reached end-of-life, in terms of support, which had not been engineered for the kind of resilience the law firm required, he explained.

“When I joined the firm, the environment was very reactive and the team was fire-fighting. Only 20% of the environment was virtualised.”

The environment comprised Windows XP desktop PCs with CRT monitors, and a mix of Windows 2000 and 2003 server operating systems, built around an HP SAN. The IT supported key legal systems such as the Interwoven document management system, which holds almost 5.5 million Word and PDF documents.

Thomas said the HP SAN had not been set up with redundant controllers or network paths, so it represented a single point of failure on the network. Initially he assessed whether the existing HP SAN could be hardened to make the environment more resilient, but realised it would not meet the needs of the business for resilient data paths and controllers to eliminate any single point of failure.

It was unsuitable for the firm’s medium and long-term server requirements, and would also required huge amounts of investment for high availability. With this in mind, he decided to buy a Dell Compellent Storage Center SAN.

“The SAN is paramount to our network. Previously we installed the server operating systems on the local server disk drives, but we now hold the server operating system files on the SAN. So if we lose the SAN we  not only lose access to our data,  we would also suffer server outages.”

Migrating SANs

The migration from HP to Dell storage hardware was relatively easy as the SAN being replaced had not been optimally set up, Thomas explained. The law firm used Atlanta to help migrate and implement the new Dell SAN. He said: “We took snapshots of the server drives on the old SAN and created new virtual servers, then restored those servers on the new Dell Compellent SAN.”

After taking the snapshot, Thomas copied  the virtual machine images onto the new environment. This involved moving existing virtual machines on a VMware 3.x environment to VMware 4.0 on the new environment. He said, “The migration took eight weeks. Key systems like Microsoft Exchange and our document management system were switched-over out of office hours.

As part of the SAN migration, Thomas decided to run iScsi, the location-independent data storage and retrieval protocol built on IP networking. He said, “We spent a fair amount of time configuring core Cisco switches. We had to set up iScsi on the core Cisco 3750 switches that were introduced three year ago and build resilience."

Performance boost

Stevens & Bolton uses three VMware hosts (ie physical servers), on the Dell-Compellant SAN. In spite of warnings from some suppliers that any performance-related issues would not be supported in a virtualised environment, the company is running to 25 virtual servers. Thomas said teh company has virtualised about 95% of our physical servers into the virtual environment on Compellent. "I am quite sceptical about putting all eggs in one basket, but I was really impressed with how well Compellent faired with performance.”

The performance improvement resulted from the improved Cisco core network, which was optimised by Atlanta, combined with an  increase in the  number of hard drives used, which, he said, gives a parallel speed improvement.

Upgrade plans

Having upgraded the practice management and document management systems, which was completed last year, and migrated 70% of its servers now 2008 R2, the company is now planning a Windows refresh. This will involve moving desktop PCs onto Windows 7 and upgrading to Exchange Server 2010.”

Thomas is not betting on the availability and stability of Windows 8, when it ships. He said, “We have downloaded Windows 8  and it it looks very sexy and new. We would like to purchase Windows 8 licences and install Windows 7. ”

He also believes the upgrade to Windows 7 will be a traditional upgrade, rather than migrate desktop users onto a virtual PC environment (VDI). He said, “We will look at VDI in 2013/14.”

Easier administration

The IT team at Stevens & Bolton comprises just five staff, who provide support for the whole business. According to Thomas the Dell Compellent management tool requires a very basic knowledge to get by. He said any member of the team can provision hard drive space from Compellent, and build, a new server. The web-based management tool dumbs down SAN technology, making it easier for his small multi-skilled IT admin team to work with. IT environment web interface IT teams can have remote access to their systems, allowing them to manage or make adjustments wherever they are.

The company runs three Dell Compellent snapshots in addition to daily tape backups.

Given the nature of the business, the IT team is sometimes asked to restore an entire Exchange InBox. Thomas said the team is able to use the snapshot feature in Compellent to restore the Exchange server, then runs an iScsi initiator on a PC to connect to the snapshot file.  PowerControls, a tool from Kroll OnTrack, is then used to emulate the Exchange server, in order to access an individual mailbox. We can select the mailbox and recover an individual [Outlook] PST file,” Thomas added.

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