Choosing the perfect rack server
Ready to buy your first server? Or looking to upgrade old hardware? Dave Mitchell explores the huge advantages of the latest systems
The cloud has its place, but in-house servers are still hugely valuable. If you’re a growing business, you might be planning to buy your first purpose-built server soon; in a more established organisation, you might have older hardware that’s due for an upgrade.
Whichever camp you fit into, you’ve never had it so good. Intel’s huge range of server CPUs allows you to configure a system that’s perfectly tailored to your workload.
In this month’s Business Focus, we test-drive rack servers from four big names – Broadberry Data Systems, Dell EMC, Fujitsu and Lenovo. Although we didn’t specifically ask for 2U rack systems, all four vendors chose this format – a clear consensus that it offers the ideal balance of efficiency and expandability for an SME. Indeed, you might be surprised how much power can be packed into one of these compact frames.
Heavy metal
The first thing to decide is what sort of processor you need. Intel’s entry-level Xeon E3-1200 is still an option, but it’s limited to single-socket systems with no more than 64GB of RAM. These days we would only recommend it for very lightweight roles.
For most businesses, it makes more sense to invest in Intel’s newer Xeon Scalable CPU family. This comprises no fewer than 58 CPU models, grouped into four designations – Bronze, Silver, Gold and Platinum – which reflect their differing features and capabilities.
For a small business with a light to moderate workload, the Bronze and Silver levels are likely to be most suitable. For a more demanding role, some of the more affordable Gold models might be appropriate. Don’t worry about the Platinum range – it’s aimed at data centres and other enterprise-scale environments.
This simplifies your choice a lot, as the Bronze family consists of just two processor models, namely the six-core Xeon Bronze 3104 and the eight-core 3106. Both run at 1.7GHz and support up to 768GB of 2,133MHz DDR4 memory. They can be used in either single- or dual-socket servers, but lack HyperThreading (HT) and Turbo Boost capabilities.
The Silver series, meanwhile, consists of five models, with core counts ranging from four to 12, at speeds from 1.8GHz to 2.6GHz. Memory speed is also raised to 2,400MHz, and there’s support for HT and Turbo Boost as well. All of this makes them much more capable than the Bronze models when it comes to running business-critical services.
Above that, the Gold family is split into the 5100 and 6100 groups. All of these can be used in single, dual or four-way server platforms; the main architectural difference is that the 5100 chips have a 2,400MHz memory speed, whereas the 6100 models hit 2,667MHz. The 6100 series also has greater overall memory bandwidth thanks to a third Ultra Path Interconnect (UPI) – the latest high-speed communications mesh, which replaces the older QPI.
Buy only what you need
It’s tempting to aim high when configuring a server – but curb your enthusiasm, as the higher-end chips are a lot more expensive. For example, a Bronze 3104 CPU costs around £250 whereas a 16-core Gold 6130 could cost you over six times as much.
And the great thing about the Xeon Scalable range is that if your needs grow to outstrip the capabilities of your chosen CPU, you can easily upgrade it. All models use the same massive LGA 3647 socket, so if you find your Bronze CPU is running out of steam, you can simply drop in a faster, more core-heavy Silver or Gold model and keep on trucking.
We’ve just one caveat: look out for the heat-dissipation capabilities of your chosen chassis. Bronze and Silver CPUs all have a low 85W TDP, which means they’ll work in any enclosure – but not all chassis will support the higher 125W TDP of more powerful processors. That’s something to check if you might want to upgrade your processor at some future point.
Storage decisions
While you can easily upgrade a Xeon Scalable CPU, things are trickier with storage: if you need to expand an overfilled RAID array, you’re looking at an extended period of downtime or degraded performance. It often pays to start off with enough storage to last the expected lifetime of your server.
Be aware that some blue-chip server providers will require you to buy their recommended disks, at a price that may not be competitive – or risk invalidating your warranty. Independent vendors such as Broadberry Data Systems, by contrast, expressly allow you to install your own hard disks.
When it comes to choosing drives, SATA disks offer the best price-to-capacity ratio, with large form factor (LFF) models currently available in capacities up to a mighty 12TB. For faster performance, consider Nearline SAS (NL-SAS) or SAS drives – but don’t forget that these will be more expensive, and you’ll need a suitable controller card to support them.
On that note, check that your server’s RAID controller offers a minimum of RAID1 mirrored and RAID5 parity arrays. RAID5 is normally the best choice for a small business, as it offers a good balance of capacity and fault-tolerance, and can be easily expanded if need be. RAID6 protects against two simultaneous drive failures, but it’s expensive in terms of lost storage space and some vendors only offer it as a paid-for upgrade.
Backup and management
A final point to consider when buying a new server is software support – and that starts with backup. Don’t assume that RAID will keep you safe: you need a proper backup strategy, to ensure the data and applications on your new servers are protected against threats such as fire and theft. There’s a huge range of products to choose from – see our A-List from p16 to check out our recommendations.
Think about remote monitoring and management tools, too, to keep track of the health of your servers. Most vendors now offer sophisticated web consoles capable of delivering a wealth of information. Some also offer a dedicated management port, so you can separate this traffic from general data services. It’s even possible to get full remote control of the OS – though some vendors only provide this as an optional, chargeable upgrade.
If this seems like a lot to think about, count yourself lucky: SMEs have the biggest choice ever when it comes to rackmount servers. On the coming pages we test a range of contenders, with different levels of processing power, expandability and features to suit all budgets and workloads. Read on to see which is the best fit for your business.