The cloud presents an entirely new set of value propositions for enterprise computing environments, offering myriad benefits including application scalability, improved economies of scale, reduced costs, resource efficiencies and more. Such benefits enable companies' vision of the truly dynamic data center and further a new level of agility and nimbleness that is unfathomable with the traditional silo computing model.
In my experience, the typical hardware procurement time can be up to 12 weeks. Furthermore, the operational expenditures (OpEx) associated with in-house hardware can be as much as 70 percent of the initial cost of the hardware per year. With the typical life of the hardware running between three and five years, the total cost of ownership of the hardware can be between three to four times the initial hardware acquisition costs.
When it comes to cloud choices, organizations today can choose between traditional clouds, which offer virtual machines (VMs) that are extremely easy to use but abstract disk, memory and CPU and come with a sizeable performance penalty; or bare metal clouds, which allow users to custom-design hardware dedicated to their applications and provide roughly a 4x greater performance than traditional VM clouds.
Security concerns, the potential of breaking regulatory compliance in a multi-tenant environment and lower performance associated with VMs were the main reasons why security-sensitive organizations originally were reluctant to move their data to the cloud. These concerns gave birth to dedicated server offerings from cloud providers. Today, these dedicated servers are offered as dedicated virtual servers or dedicated bare metal servers.
Dedicated Virtual Servers
Dedicated virtual servers possess two attributes that bare metal servers do not: hypervisor and multi-tenancy. The hypervisor is used to virtualize the resources of physical machines, creating multiple virtual machines on each physical server for a multi-tenant environment.
Dedicated virtual servers provide complete isolation and protection of an organization’s data in a multi-tenant environment from both outside intrusions and other customers sharing the same cloud provider infrastructure. Virtual LANs (VLANs) are used to interconnect all compute and storage resources and the access to vCenter. The operations management suite for all virtualized resources goes through an SSL tunnel, while direct access to the virtual machines is available through a VPN. This combination of a VPN and an authentication token ensures that all exchanges are totally secured between the user and the virtual machines.
Organizations have the ability to limit user access to VMs to specific and limited IP addresses, and vShield Zones—an application firewall for each virtual data center—protects the entire infrastructure. These measures guarantee the security of all transferred data.
VMs are extremely easy to use but abstract disk, memory and CPU, and they come with a sizeable performance penalty. Most cloud service providers offering dedicated virtual servers do not allow customers to pick RAID level or drives (only volumes). Others limit the volume size or restrict sharing of volumes among customers (hence, no clustering). A few cloud service providers provide low-level API-level access and allow their customers to pick their own snapshots and remote mirroring policies and frequencies.
However, in the dedicated virtual server scenario, the cloud server is running in a virtualized environment utilizing a hypervisor layer, which allows each physical server to be shared between many users. This sharing often results in resource contention due to oversubscription in a multi-tenant environment and can result in performance issues.
Bare Metal Servers
Bare metal cloud services are essentially physical servers that can be deployed on demand and billed hourly. They can offer significant improvements over virtualized infrastructure as a service in performance, consistency and cost-efficiency for many applications. Bare metal cloud services combine the advantages of traditional dedicated servers within a company's firewall without the OpEx associated with in-house servers.
The hypervisor layer consumes a big chunk of server’s processing power, but it is not needed in a bare metal server since resources are not being shared. Therefore, the server’s processing power is available to the application, resulting in better performance than a comparable virtualized server.
Furthermore, unlike dedicated servers, which can take days or weeks to deploy, bare metal cloud resources can be provisioned in a matter of minutes. Some of the advantages of bare metal cloud services are:
- Resources are dedicated to a single customer
- Greater processing power and input/output operations per second (IOPS)
- More consistent disk and network I/O performance
- No fixed instance sizes, no wasted resources
- Balanced load distribution (no hot spots)
- Quality of Service (QoS) guarantees to eliminate the noisy neighbor problem in a multi-tenant environment.
Most bare metal cloud service providers offer granular pay per use at per-minute or per-hour intervals (some charge per five-minute intervals). For IaaS storage, most cloud service providers charge by drive, while others offer predefined disk packs. Most allow their customers to purchase additional IOPS per drive. While most cloud providers offer service level agreements (SLAs) for availability, some bare metal cloud services providers also offer SLAs for performance, including IOPS for storage.
Applications and workloads that require direct access to physical hardware, such as databases and calculation-intensive applications, benefit from the performance of bare metal clouds. Further, workloads that should not be virtualized are strong candidates for bare metal clouds.
In today’s economic turbulent environment where IT budgets are constantly under the microscope, businesses are eager to graduate to exponentially more attractive products that can give them fundamental advantages in IT, resulting in increased competitiveness in their markets. Dedicated virtual servers or bare metal servers present fiscally attractive value propositions for enterprise computing environments that are hard to ignore.
Ashar Baig is president and principal analyst and consultant at Analyst Connection, an analyst firm focused on cloud computing, IT products and services and managed service providers. He has more than 18 years of high-tech industry experience. Baig also is founder and manager of the LinkedIn Cloud Backup group.