How Storage Area Networks Can Save The Day!

Being responsible for running a company network is usually smooth sailing, but there are a few situations that will make for a very bad day. A critical component of your server will fail and all of your applications and file servers will be down. Then you will be at the mercy of a computer repair man who may or may not be able to get your systems up in a day or two.

Don't you wish there was a way to keep that from ever happening again? Big companies and service providers can't afford to have any downtime, so they have elaborate systems of redundant hardware that automatically take over when something goes wrong. Until recently, smaller businesses couldn't easily afford redundant systems. Now there are plenty of affordable options that can harden a small business network.

Divide and Conquer with SANs

The first step in hardening computer networks is to take a divide and conquer approach. This is where you separate the file storage from computing power through the use of Storage Area Networks, or a SAN.

A SAN presents persistent storage to a Windows or Linux server completely transparently. Both Windows and Linux effectively use a SAN just like how an operating system uses a local hard drive.

With a SAN one may easily create backup computer resources and even have off-site backups. With a full SAN deployment it only takes a few keystrokes and mouse clicks to recover from a hard drive failure. A SAN recovers from hardware and software failures within minutes instead of days.

I Want a SAN Now!

Sounds exciting, but how exactly does one buy a SAN? Just a few years ago, the answer would be "call up a SAN vendor and pay a whole bunch of money." The reason was that the SAN computer interconnects and networks were specialized products. The computer boxes that were sold as SAN storage servers were also specialized and commanded a high price to guarantee compatibility.

Fortunately the march of computer technology has make everything cheaper, so that even SAN technology is now affordable. Through the use of standard network and computer equipment, the cost of a SAN has come down nearly ten-fold in the last five years.

Two factors share the honor of bringing SANs to the masses: iSCSI running on Gigabit Ethernet and Free Open Source Software (FOSS). Cheap and fast gigabit Ethernet replaces the specialized computer interconnects sold by SAN vendors. The FOSS stacks FreeNAS and OpenFiler both turn standard computer server hardware into SAN storage servers using a TCP/IP protocol called iSCSI. FreeNAS and OpenFiler used the tried-and-true FreeBSD and CentOS operating systems, respectively.

My NAS must do iSCSI?

Servers built with FreeNAS or OpenFiler are called NAS devices, where NAS stands for Network Attached Storage. NAS devices are standard computers configured as a server, with persistent, redundant storage being fast hard drives or maybe SSDs.

As a Dell Partner, Berkeley Logic has found an extremely practical way to create an OpenFiler or FreeNAS server is to order a low-end Dell server with the necessary storage. We make it a single-socket system with 16 GB of RAM. The R310 has worked fine for us. We prefer to use hardware RAID with the PERC controllers, but OpenFiler and FreeNAS are perfectly happy without the extra card. Use a 4 GB SATA DOM (Disk On Module) to install the NAS operating system. Set the server to boot to the SATA device, and away you go!

If you don't feel like rolling your own NAS device with FOSS, there are plenty of affordable iSCSI NAS devices are coming onto the market all the time. Many of them are based on the same Linux and FreeBSD kernels as OpenFiler and FreeNAS.

Be careful, though. Most NAS devices on the market are not iSCSI-compatible. One of the latest compatible market entries is the Buffalo TerraStation iSCSI, which comes in 4 TB mini tower and rack-mount configurations for well under $2,000.

How do I recover with a SAN?

A SAN gets its power by switching connections between servers quickly and easily. Here's a scenario on how a SAN works. A basic SAN configuration is to segregate all of your file shares into an iSCSI volume on a NAS. A separate server computer has Windows Server 2008R2 installed and running. The Windows server attaches the iSCSI volume and publishes the file shares using enhanced Windows DFS file sharing.

Suppose your Windows file server goes down due to a new malware infection. A backup file server can be brought online and attach to the same iSCSI volume and take over where the old server left off. The advanced capabilities of Windows DFS (Distributed File System) makes the server switch invisible to end users.

NAS devices are much more reliable than standard Windows servers due to their small attack surface and advanced security capabilities. Nevertheless, it is reassuring to have a backup NAS sitting around somewhere ready to take over if the main server goes down or needs maintenance.

The combination of Windows DFS replication and iSCSI makes is simple to make an exact, dynamically-updated backup of one iSCSI volume to another iSCSI volume. This backup can be made even better by putting the backup NAS at a branch office location connected by the company Wide Area Network (WAN), thus helping to implement a sophisticated disaster recovery plan.

Sounds Good, What's Next?

Upgrading to a basic SAN architecture mainly involves carefully reviewing all of your file shares and organizing them into a Windows DFS hierarchy. After you've implemented DFS, then it's time to bring your new NAS online. Configure the NAS to publish an iSCSI volume, and attach it to your server. Copy all of your files into the new iSCSI volume, move the DFS targets, and your're in business!

DFS can be quite an undertaking in terms of learning Windows. Be sure to check out some links at the end of this post for some resources to get you going.

But, Windows DFS isn't technically needed to get going with iSCSI. DFS is strongly recommended, however, because it implements fail-over transparently to your users. DFS has the added bonus of making iSCSI volume replication a snap.

You may also be wondering how to affordably have a backup to your Windows and Linux servers. One way is to use a Virtual Machine Hypervisor like VMware or Windows HyperV and "physical to virtual" tools to create a backup of all of your servers and keep them on stand-by in your hypervisor host. More on the power of virtualization in hardening a small business network in a future post!

Good Luck!

Affordable SANs are now within the reach of many small business network owners. Best wishes as you undertake this exciting upgrade that makes sys admins sleep easier. If you're in the East Bay be sure to give Berkeley Logic a call to help you with your SAN network needs at 510-228-4500.


Vernon Keenan -- June 23, 2012

Resources

• SAN Vendor: EMC - web
• SAN Vendor: Dell - web
• SAN Vendor: HP - web
• NAS Software: OpenFiler - web
• NAS Software: FreeNAS - web
• FOSS: CentOS Linux - web
• FOSS: FreeBSD Unix - web
• Microsoft DFS How It Works - web
• Microsoft DFS Step-by-Step Guide - web
• Microsoft DFS Replication Overview - web
• NAS Vendor Information - WhichNAS - web

Enterprise Computing

Berkeley Logic sells and installs a wide range of laptop, desktop and server computers suitable for organizations of any size. We can meet or beat advertised prices for many business-class computer systems, plus we will deliver and install new equipment at your business location.

Berkeley Logic recommends some of the features found in business-class computer brands. For example, when one compares business-class computing brands like Dell Optiplex and Lenovo Thinkpad to more consumer brands like HP Pavilion or Acer Aspire, a big difference is the length of time a particular model stays on the market.

The short lifespan of IT products is one greatest frustrations of business computer buyers. The rapid rate of change means it is usually impossible to buy a new version of the same computer you bought only six months ago.

Being able to buy a computer that has the same basic architecture, but has all the latest and greatest processors and memory components, allows Berkeley Logic to use advanced system management techniques to greatly streamline buying new systems. The is a leading reason why we recommend Dell Optiplex and Latitude for business computer buyers.

When building a business network Berkeley Logic uses disk imaging and network profiles to cut-down on per-computer setup chores. Estimates for installation and setup charges for business network installation vary according to individual customer requirements.

Today we're starting a new series where we are posting some of newest pages from our updated web site, www.berkeleylogic.com.

To kick it off, here's a very timely subject: Cloud Computing. -- Vern Keenan

Cloud System Integration

The Cloud refers to any Internet-based service that performs a business or personal information function. Yahoo Mail and Hotmail were among the first cloud-based services introduced in late 1990's.

Today you can use the Internet to run practically your whole business with services ranging from Box for file sharing to Salesforce.com for a sophisticated customer relationship management system.

Amazon Web Services and Microsoft Windows Azure has taken it a step farther by offering pure-platform solutions. Today it is possible to have a new Windows or Linux server up and running on the Internet in less than 10 minutes. With this type of service, one may run any type of application. The only bottleneck will be the speed of your Internet connection.

Small enterprises have mixed feelings about the cloud. On the one hand, it's great to not buy servers and other computer gear for the office. On the other hand, one can worry about the security and performance of data stored on someone else's server.

The reality is that a hybrid system of having some of your data stored in a server in the office, and other data stored in the cloud is the best solution. Berkeley Logic helps you evaluate available cloud-based services and create a hybrid environment tailored to your requirements.

Berkeley Logic integrates the business operations of our customers into the cloud in several key areas of technology.

• Email Migration. As a partner with Google Apps and Microsoft's Office 365, Berkeley Logic helps customers find the best way to move from an in-house email server to a hosted service. Every migration is different, and they vary according to usage patterns.
• Advanced Cloud Backup. Keeping backups at an offsite, professionally-managed data center is becoming the norm in IT best practices. Berkeley Logic works with your existing IT infrastructure to install automatic and continuous backup mechanisms. Plus, we can help you re-architect your existing server setup into a Storage Area Network (SAN) that integrates with advanced backup tools like the Amazon AWS Storage Gateway.
• New Application Deployment. Berkeley Logic can help you create a private cloud that makes your proprietary applications more usable, scalable and safe. When you buy a software product from a vendor who doesn't have a hosted version, Berkeley Logic can use Amazon AWS or Microsoft Windows Azure as a platform for your new software instead of buying a new sever.
• Application Migration. If you have Windows or UNIX applications running in a server you own, you may avoid upgrading that server by migrating the applications to the cloud. Berkeley Logic can take those applications and move them to the cloud, and ensure that all your users still have the same functionality they had before.

If you're thinking about making the leap to cloud computing then give Berkeley Logic a call at 510-228-4500 for a free consultation on what combination of on-premises and cloud-based services would work best for you.