Lorne Lavine, DMD
The modern dental office continues to evolve at a rapid pace. Many dentists are building or upgrading their practices to achieve their goal of a paperless or chartless system. This involves many components, including electronic chart notes, digital charting, intraoral camera images, digital X-rays, and digital camera photos. As more practices move towards a digital format, greater and greater stress is placed on the computer and network systems that support it. Of all the computers in the network, the server is the most important. It has many unique features that separate it from other computers on the network. In this article, we'll evaluate the unique features of a server.
Hard drives
Many varieties of hard drives can be found in computers. In the past, desktop computers contained IDE drives and servers had SCSI drives. IDE drives are relatively inexpensive. They are also easier to set up. SCSI, which stands for Small Computer System Interface, is a far more developed (and complicated) system. Overall, the SCSI interface is technologically superior to the IDE interface. It allows for more expansion, supports more devices, allows for better multitasking, use of more high-end devices, more types of devices, and more performance-enhancing features. SCSI drives spin at a higher rate than IDE drives, as high as 15,000 RPM. While IDE is adequate for very small offices, a newer standard has emerged that is usually a better choice. Called SATA, or Serial ATA, the drives spin faster than IDE drives. The cables also are much smaller, so they can be used in small computers where reduced airflow is a concern.
RAID drives
While we have previously talked about RAID drives in an earlier issue, it makes sense to briefly review these drives. RAID stands for Redundant Array of Inexpensive Disks. It is a system of using multiple hard drives for various reasons. For desktop computers, some manufacturers create a RAID 0 array, where the hard drives are configured to share the duties of the computer. While this increases speed, it is not appropriate for a server. The server RAID system is designed for redundancy. Multiple hard drives are mirrors of each other, which creates redundancy for the server. The concept is built around the thought that if a hard drive fails (still relatively rare), there should be a minimal amount of down time for the office to get back up and running. With mirrored drives, each drive contains a complete copy of the main drive. If the first drive fails, the second drive will take over and allow the office to keep functioning. The RAID systems that are most common for servers in a dental office are either RAID 1 (two drives) or RAID 5 (three or more drives).
For most desktop systems, the hard drives are housed inside the computer, where they are not easily accessible to the user. Most dentists and dental office personnel are not comfortable opening up a computer to take out a hard drive. One option with servers is to have the hard drives accessible on the front of the computer. By simply pushing a button, a faulty drive can easily be removed from a server and replaced with a good drive, even while the server is still running. This is known as "hot swapping."
Memory
Most servers will use a special form of memory known as ECC to create a more stable system. ECC, or Error Checking Code, is designed to help correct errors. ECC RAM, coupled with a proper memory controller, is able to correct memory errors instead of letting them get corrupted, possibly corrupting your data. This usually translates into fewer system crashes.
Redundant power supplies
All the redundancy in hard drives won't help much if the server doesn't have power! The power supply is an often overlooked, but important, component of the system. To eliminate loss of power as a reason for server failure, many servers will be configured with a second power supply. The disadvantage to this is that not only does it increase the size of the server case, it also tends to create significantly more noise because the power supply fan is frequently the noisiest element of the server.
While many offices can function without all of the features we have discussed, offices that are truly paperless or chartless should invest in a server designed to keep the practice up and running.
Lorne Lavine, DMD, practiced periodontics and implant dentistry for more than 10 years. He is an A+ certified computer repair technician, as well as Network+ certified. He is the president of Dental Technology Consultants, a company that assists dentists in all phases of technology integration in the dental practice. He can be contacted by email at [email protected] or by phone at (866) 204-3398. Visit his Web site at www.thedigitaldentist.com.
