A network server is a powerful computer used to store files and run programs centrally. You can create a computer network without a server, but having one can be useful.
This briefing covers:
- What a server is used for.
- How to choose a server.
- How to keep your server secure.
1 Using a server
A server is used to store files and run centralised applications, such as your customer database.
1.1 Use a network server to:
Businesses with a large number of computers may need to spread the load across several servers, although virtualisation can help you do more with a single server (see 2.4).
1.2 Some applications may dramatically slow your network if you run them on your server.
They may require a separate server, used just for them. Such applications can include:
- Large shared databases.
- Complex internal mail systems.
2 Types of server
The vast majority of network servers are high-performance PCs, designed to be used as servers. Some businesses with specialised needs use Apple servers.
2.1 There are clear reasons PC servers dominate the market.
- Hardware is standard, so you can purchase servers, components and add-ons from different suppliers.
- These servers can run the most popular network software (see 4).
- PC-based servers work well with most business software, which is written for the PC.
2.2 ‘Thin client’ systems are becoming more common.
- With a thin client system, your company PCs are replaced by cut down terminals connected to the server.
- All data processing is done on the server, and all data is stored centrally.
- Thin clients are very secure, because data cannot be copied to individual terminals.
2.3 Server virtualisation can let you do more things with a single server:
- Virtualisation uses special software to split a single physical server into several ‘virtual servers’.
- Each virtual server function as a completely seperate server.
- Virtualisation lets you run several complex applications at once, without them interfering with each other.
- Modern servers can be very powerful, so virtualisation lets you use them to their full potential.
2.4 There are some general rules to consider when purchasing a new server:
- Your server will be a key piece of hardware so pick the best you can afford.
- Always look at the complete package, including warranties, support and expandability.
- Budget for extras.
For example, you may want uninterruptible power (see 3.4) and a backup facility (see 5).
- Setting up a server is complicated.
Seek help from an expert or a reliable IT supplier.
Using the cloud instead
You can use cloud computing services (sometimes called hosted applications) to do many jobs that have traditionally required a server.
With cloud computing, your data is held on a server located outside your busiess. To access files and services, you log in over the internet.
Individual cloud computing services can help you with specific tasks, like backups or accounting. You can also purchase ‘cloud servers’ that perform all the functions of an in-house network server.
Cloud computing offers a number of advantages over buying a server:
- You pay monthly, allowing you to spread the cost (although the cloud may not work out much cheaper overall).
- Your cloud provider usually takes care of all the administation and technical support.
- It’s very flexible - you can add or remove users instantly, and you aren’t tied in to a long contract.
- Hosted applications are accessed across the internet.
- It makes remote working easy, because cloud services can be accessed from anywhere.
Although it’s easy to sign up to cloud services, it’s important to look before you leap:
- Make sure your cloud supplier is trustworthy, as you’ll be relying on them to take good care of your data.
- You need an internet connection to use cloud services, so make sure yours is fast and reliable.
- Check what level of support you get. Are you confident your cloud provider will be there to help?
3 Server hardware
Your server will be on all day, every day. This means the hardware needs to be very reliable.
3.1 Choose a network server with a powerful processor.
- Most servers come with dual or quad core processors.
These are effectively two or four processors in one, so a quad core processor running at 2GHz is more powerful than a dual core processor running at 2.5GHz.
- The processor is not the only thing that determines server performance.
The other hardware elements are
- Look for at least a dual core 3GHz processor.
If you have lots of users (up to 30) or run demanding applications, you can opt for one or more quad core processors.
3.2 Ensure you have enough RAM available.
You will be able to access files faster with more RAM.
3.3 The hard disk is the part of your server that is most likely to fail.
You should minimise the risk of this happening.
- Ensure the hard disk is large enough for your needs.
This figure is largely determined by the kind of files you use and what applications you run on the server. As a minimum, get 500GB.
- Consider having several hard-disk drives if you need extra capacity.
You will probably want to invest in a RAID system, which is designed to tolerate a drive failure and keep on working (see 5.3).
3.4 You may need some additional components.
3.5 The cost of your server will vary considerably depending on the specification.
4 Server software
A typical network server may have several different kinds of software installed.
4.1 The two main network operating systems are Microsoft’s Windows Server and Linux.
- • Both Windows Server and Linux supply the features required on a general-purpose server.
- The systems work with each other, so you can connect Windows PCs to a Linux server.
- You can use both systems with a wide range of processors and hardware.
4.2 You may need additional software to monitor and control everything attached to your network.
- Managing the network becomes more involved as your network grows.
- Make sure any hardware you buy can communicate with the network management software you use.
You can use the server to install and manage software centrally.
- Once the software on your server, you can roll it out to individual computers in your company.
- This makes it easier to keep all the software in your business up to date.
- Buying software designed for network installation can be cheaper than buying individual copies.
4.4 Some software is supplied as client-server applications.
4.5 You may need additional software.
- Virtualisation software makes it easier to use your server for several different things (see 2.4)
- Intranet software enables you to host your intranet on the server.
- • Mail server software lets your server take care of all incoming and outoing email.
- A collaboration package will let you create shared workspaces on the server.
- Security software is key (see 5.4).
Servers usually hold a large amount of important company data, so can be a target for hackers or online criminals. Like any computer, servers can also suffer software crashes or hardware problems.
5.1 Fit your network server with an uninterruptible power supply (UPS).
Essentially, this is a battery that can keep the server running during a power cut.
5.2 Back up your data.
- Choose a convenient, fast backup device.
You might use a mirroring system (to copy information onto a second hard disk), a tape system or online backup.
- Ensure you can automatically back up at least one day’s worth of new data.
- Use backup software to automate the backup procedure.
This allows you to run backups when the system is not being heavily used.
- Backup new data every day and take a full copy of the entire hard disk every week.
- Store a full copy of the system off site and test restoring from your backup at least every three months.
5.3 You can protect against hard disk failure.
- Use a RAID (redundant array of independent disks) system.
- Raid spreads your data across several hard drives so it can be reconstructed even if one of the drives fails.
- RAID should be used alongside a seperate backup system.
5.4 Use security software to protect your server.
- A security package should include virus, Trojan and spyware protection, plus a software firewall.
- Use a hardware firewall to provide an additional layer of protection.
5.5 Keep all server software up to date.
- This helps protect your server from hackers targetting vulnerabilities in the software.
5.6 Make sure your server is physically secure.
- Keep your server in a locked room with access restricted to essential personnel only.
- Consider keeping it off the ground floor to protect against flood damage.
A server should last for at least four or five years. Most are designed to be easily upgraded.
6.1 You may need to upgrade your hardware.
- Adding more RAM will improve the speed at which your network server responds (see 2.2).
- You can add additional hard drives when you need more storage.
6.2 You may need to upgrade your software.
Upgrading or changing network software may involve reconfiguring all the computers connected to the server.
- You may occasionally need to update your network operating system.
Upgrade your network server at a time when nobody else needs to access the data on it.
Make sure you have a complete backup before making changes, in case you need to start again.