Server Technologies
Most networks should have some form of file service. This technology allows for easy access to shared files, and can simplify the data backup needs of the organization. For small networks (less than 10 computers), the built in peer-to-peer networking of the recommended operating systems is adequate for most needs. For larger networks a central file server running a “network operating system� is recommended. The decision about which server environment to use depends on a lot of things.
   Staff size – the more active computer users your organization has, the more likely you are to need a dedicated server.
   Data usage– Organizations that are heavily data dependent, which share large files or actively make use of a large number of files, will more likely need a dedicated server.
   Security – Organizations that have confidentiality or security concerns would most likely benefit from the increased security measures available from a dedicated server.
Peer-to-peer file service
Though peer-to-peer file sharing allows all computers on a network to share files with all the other computers, in practice this becomes very difficult to manage and maintain. We recommend setting up only one computer to share files. This “master peer� should be the computer with the most resources, as file sharing will be a burden on the computer. As other computers will rely on it for access to files, it will need to be kept powered on all the time. Peer-to-peer file sharing has limited security functionality, and may not be suitable for storing sensitive information.
Dedicated file server hardware
A dedicated file server computer needs to robust and reliable, as it often becomes the central point of an organization’s network. Server computers should have the following minimum specifications, Pentium III 1 GHz processor, 256 MB RAM, 40 GB redundant hard drives, functioning CD-ROM and floppy drives. For a Macintosh based network, a minimum 800 MHz G4 processor, 256 MB RAM, redundant 40 GB drives, and a functioning CD-ROM drive.
For purchasing new servers, we recommend the following minimum specifications. Pentium 4 2 GHz processor, 512 MB RAM, 80 GB redundant hard drives, functioning CD-ROM and floppy drives. For a Macintosh based network, a minimum 1.5 GHZ G5 processor, 512 MB RAM, redundant 80 GB drives, and a functioning CD-ROM drive.
When possible, organizations should use specialized server hardware, as opposed to a tricked-out desktop computer. Server hardware is designed for better performance and more reliability, and does not include components such as sound cards or fancy graphics cards, which are unnecessary in a server and consume resources.
Server operating system
File server computers should use a dedicated server operating system. Unlike desktop operating systems, server operating systems (also referred to as network operating systems) include tools to increase security and provide other services to computers on the network. We recommend the following server operating systems:
Windows 2000 Server
Windows Server 2003
Windows Small Business Server 2003
Macintosh OS X Server 10.2 or greater
All these operating systems include powerful file sharing software, centralized user accounts, flexible security features, Internet and local network services, easy-to-use administration tools, and much more.
Macintosh and Windows servers have very similar functionality, and in a cross-platform environment (Macintosh and Windows client computers), are essentially equivalent. The real differentiation is in cost. Apple hardware tends to be somewhat more expensive than equivalent PC hardware. On the other hand the retail software costs for the Macintosh OS are much lower than the Windows costs, as the OS is bundled with Apple’s server hardware and does not require per-user licenses. However the heavily discounted donated Windows software available from TechSoup Stock greatly lowers the cost of a Windows implementation for most non-profits. Organizations without access to TechSoup Stock will need to carefully cost out Windows vs. Macintosh options.
Server appliances
An option for organizations that do not have heavy server requirements is a dedicated server appliance. These are small devices that provide file service, backup service, and other server functions without the need for a full size computer. These devices usually include an embedded version of Linux that is built-in to the hardware and that doesn’t need to the same level of care and feeding as a full-size server installation. The tradeoff is in limited performance and expandability options.
UPS
In addition to the file server computer itself, we recommend that organizations purchase an uninterruptible power supply (UPS) to use with the server. A UPS is a combination surge protector and battery that can protect the server from power spikes and outages. Most UPS can signal to the server that a power outage has occurred, allowing the server to shut itself down gracefully, which is necessary to avoid data loss.
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Print services
While we generally recommend that organizations purchase network enabled printers that include integrated print servers, some organizations may find the need to use a computer as a print server. All the recommended operating systems are capable of sharing a printer to the network. Be aware however that client computers sharing a printer, especially a cheap inkjet printer, can take a significant performance hit when the shared printer is active. Connecting a printer to a dedicated server can sometimes effect the server’s performance, but can allow for very fine control over who can print to the printer, when they can print, and what they can print.
Network authentication
One of the key features of a client/server network is that network operating systems allow an organization to centralize all user accounts and user data on the server. With this setup, maintaining user accounts is simplified. As is client computer setup.