How to choose appropriate server & storage hardware for an application?
One of the major factors is the minimum specification (CPU, Memory, Hard-Disk Space, etc.) required for the chosen application to run smoothly on the hardware. And with a common use of Virtualization, which allows the resources of server and storage to be used more agile and more efficient, hardware specification should also be considered for future expansion. Besides, the sizes of server room and network rack must be taken into consideration when choosing the hardware with appropriate physical dimension.
This type of server looks similar to a standard desktop PC, which is normally put on a table. It is suitable for use in an office environment without server room or network rack to keep the hardware inside. Tower-type server is normally cheaper than the other types with the same specification, but it has more flexibility for upgrades due to its larger physical dimension.
This type of server is designed for installation into a network rack, its physical dimension is optimal to fit into the standard rack unit, so it normally has limited expansion capability compared with the tower-type server.
This type of server requires a chassis to provide shared resources, such as power supply, I/O interfaces, etc. for each server. The physical dimension or foot-print per server is the lowest, so it is widely used for the application requirements that need many servers to run, but there is limited space to keep those servers.
NAS is normally used as a file-sharing server, as well as used to store data of applications that do not require high read/write speed, such as Images or Videos recorded from IP Cameras. Due to its lower cost, compared with the other type of storage, NAS is also widely used as a backup media to ensure business continuity and fast disaster recovery.
Typically, SAN has higher performance than NAS, so it is used for those applications that require higher read/write speed. Instead of LAN connection, a high-performance SAN is normally connected to servers via a dedicated network using SAN switch, which has higher performance and speed than LAN switch.
SAN is suitable for the following application requirements:
For data backup stage, the data is stored onto tape cartridges using tape drive or tape library.
For data recovery stage, the date is re-stored from tape cartridges back onto the main storage.
The data write/read speed is lower than NAS and SAN, so tape cartridge is not suitable for high availability backup & DR solutions with minimal down-time. Anyway, the main benefit of this storage type is the ability to easily keep the data cartridges off-site, which reduces the risk of losing all data in case of crisis or disaster.
Virtualization is a powerful method to manage, allocate and share computers’ hardware resources for many applications to run independently. A virtual machine can be easily assigned for each application based on its required specifications, and later on, additional resources can be flexible allocated to the virtual machine at any time.
Types of Virtualization
Key Benefits of Virtualization
The main purpose of this solution to consolidate several old physical servers into a single new physical server, which owns enough resources to handle workload from all migrated applications that run on it.
This is a redundant architecture version of the basic virtualization solution; this solution adds a second new physical server and a shared storage, so it reduces the risk of single point of failure come the single server architecture. Both servers will work simultaneously, and workloads will be allocated to each server according to its available resources. In case of one server fails, the applications can be moved to run on the other server, so it is very important to design each server to have enough resources to handle workloads of all mission critical applications.
The purpose of this solution is to have a system with “near-zero” downtime. Most components are similar to the fast recovery virtualization solution; an additional server is added into the architecture to continuously monitor the physical servers, and all the virtual servers. When an irregular event is detected, actions will be automatically taken based on pre-defined rules and steps to ensure minimum downtime of the corresponding applications.
Server Management Solutions There are many tools and software used for monitoring and management of server and storage systems in both physical and virtual environments, as well as the applications, to ensure that they will continue running without interruption. Normally, the following factors should be taken into consideration for selecting an appropriate tool.