Blade servers and rack servers are two types of servers used in enterprise environments, each appropriate for different settings and data demands. Other elements like density, power consumption and cable management are areas where one type of server may offer an advantage, depending on your setup. Both designs are distinct from traditional tower servers, which are large and stand alone, similar to tower PCs.
Let’s break down these two server styles and how they compare.
What Is a Blade Server?
Blade servers have a modular design, packing more servers into a smaller area and supporting scalability. They’re thinner and typically have some components built-in, including CPUs, integrated network controllers, memory and, sometimes, storage drives. The large server chassis, mounted in a server rack, has the important role of managing multiple blade servers at once. It provides power and facilitates components like video cards. The chassis also includes spaces for blade servers to slide into.
This design allows blade servers to operate more efficiently with fewer internal components. Users can cluster the blade servers together or operate them individually. Blade servers are great for achieving high availability and conducting maintenance or upgrades without taking the server offline. They can also scale to high processor densities, but those setups need to support more demanding thermal and electrical loads.
Blade Server Pros and Cons
With such high-performing capabilities, there are a few advantages and possible trade-offs that come with blade servers.
Pros of Blade Servers
Some pros of blade servers include:
- Power management: The chassis can efficiently supply power to multiple servers and reduce power consumption overall.
- Cable management: You only need to run one cable to the chassis, making it easier to manage. You could also potentially avoid safety concerns from tangled wires.
- Hot-swappable: You can configure blade servers to be hot-swappable for easy maintenance and repairs. They’re simple to remove and replace individually without taking the system offline. This setup also supports redundancy.
- High processing power: These servers can achieve very high processing power without taking up significant space.
- Versatility: You can host operating systems, databases, software, web services, applications and more on blade servers, which often function as multi-purpose equipment.
- High availability: Between centralized management, hot-swapping, load balancing and clustered failover, blade servers offer high availability.
Cons of Blade Servers
The possible downsides of blade servers include:
- Higher upfront costs: The initial costs of blade servers, including deployment and configuration, are typically higher than rack servers. Ongoing costs might be lower thanks to simplified maintenance and reduced power consumption, but those initial costs can require considerable capital. While the blades themselves may be more cost-effective than individual rack servers, the entire cost is more significant when you fill up the chassis with blades.
- Higher cooling costs: Since blade servers have such high densities, they often need more robust climate control mechanisms. These can drive up the cost and contribute more to energy demands than the cooling requirements of rack servers.
- Less onboard storage: With their smaller size, blade servers typically have less native storage space than rack servers. They may need to be connected to external SANs or another solution to accommodate future needs.
Blade Server Applications
Blade servers are best suited to application-specific environments that need high processing power and many servers without much physical space to spare. The dense setup and high performance can help in these settings, as well as those that need to stay scalable. Blade servers can also better meet energy efficiency goals.
If you know you need a high number of servers — around 10 or more — blade servers are generally more cost-effective. A fully configured chassis is typically more cost-effective than the same number of rack servers.
What Is a Rack Server?
While blade servers work together within the chassis, rack servers function independently. Also called rack-mounted servers, rack servers are general-purpose and can support more varied environments. They’re secured in the rack via screws or rails. Rack servers are larger than blade servers and can be stacked within the rack to save space. That larger size means they can include additional memory, CPUs and other components, making them more of an all-in-one option.
Rack servers are generally limited to environments that require a lower number of servers, due to their size and cable management requirements. While blade servers connect to the chassis for limited cable management, each rack server has its own cables. With these characteristics in mind, we typically see rack servers in smaller businesses.
Rack Server Pros and Cons
Below are some of the pros and cons of rack servers.
Pros of Rack Servers
The advantages of rack servers include:
- Performance: Rack servers can meet the demands of high-end applications.
- Compact size: While blade servers are smaller than rack servers, rack servers are easier to work with than tower servers because they mount in the rack and are more compact.
- Easier cooling: Since they often have internal fans built-in, rack servers are usually easier to cool. The rack-style design can also offer increased airflow.
- Lower costs: If you need a small number of servers, the rack-mounted option is usually more cost-effective.
Cons of Rack Servers
Some potential drawbacks of rack servers include:
- Cooling requirements: Although rack servers are easier to cool, they still require a strong cooling system, which could raise energy costs.
- Less efficiency: Blade servers tend to run more efficiently, making rack servers the less energy-efficient option.
- Increased maintenance: Dense racks call for more maintenance resources to manage and troubleshoot the servers. The increased cable management demands and clunkier size also add to the time it takes to work with rack servers.
Rack Server Applications
Rack servers are best suited to environments where no more than about 10 servers will be needed. This makes them a good fit for many small- and medium-sized businesses, especially when you factor in the lower upfront cost. With their general-purpose capabilities, rack servers can support various infrastructure demands for these businesses without taking up too much space. Rack servers are also good for creating standardized racks where a business can deploy dozens of servers at once.
Make the Most of Your Servers When Upgrading or Moving
If you’re looking to add to, upgrade or simply move your servers, exIT Technologies can help. We make it easy to securely and quickly take care of your old tech, with support for decommissioning, certified recycling, liquidation and more. If you’re upgrading to a rack server or blade server setup, we can buy your used servers, erase the drives and provide a certificate of destruction.
Whether you need to meet data handling requirements or want to maximize the value from your old equipment, our skilled team makes things simple. Data erasure, managed logistics, teardown and asset valuation are just a few of the services we offer. Learn more about how we can help you add or transition to blade servers or rack servers by reaching out to a team member today.
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