Comprehensive Understanding of rack servers

Nowadays, many small and medium-sized enterprises are joining the ranks of deploying enterprise networks to improve their core competitiveness and quickly transfer internal and external information. To achieve centralized network management and reliable use of data information, servers have become an indispensable device.

Many users still have vague definitions of servers. In fact, from my own point of view, a server is an advanced PC that executes specific service functions in a computer network. Based on the server's chassis structure, we usually divide servers into four categories: "desktop (Tower) servers", "rack servers", "rack servers", and "blade servers.

Today, we will take a Lenovo universal R510 G5 server as an example to introduce in detail what is a rack server and its internal structure.

As we mentioned earlier, a server is actually an advanced PC that executes specific service functions. This definition also applies to "rack servers ". As we all know, there is a centralized point in a computer network with a star topology, which is usually called a data center. There are various types of network devices, such as switches and routers, in the data center. These devices are generally concentrated in one cabinet. A "rack-mounted server" is a server that can be directly installed in a standard 19 inch cabinet. Generally, such a server is similar to a switch in size, not a computer.

Rack-mounted servers generally have 1U, 2U, 4U, 6U, 8U, and other specifications. Here we can refer to the "U" as a high-capacity server, the height of the standard 1U rack server is 4.445 (1.75 inch). Generally, there are fixed holes in our Cabinet that can fix various network devices. The height between the two holes is 4.445 cm, the Rack server can be fixed in the cabinet.

First, let's take a look at the front panel of this 1U rack-mounted server. The front panel of the rack-mounted server generally includes three parts: the pre-control module area, the hard disk area, and the optical drive area. Some servers still have the software drive device configured, but because there are very few applications in the software drive, most rack servers do not use the software drive as the standard configuration. The front panel of the rack-mounted server varies according to the manufacturer and product model, but the front panel of the rack-mounted Server includes these three parts.

The Front control module usually includes system status indicators, hard disk status indicators, and front USB interfaces. The indicators of rack-mounted servers designed by different manufacturers are different, we can refer to the server manual to understand the meaning of various indicator states. A front display interface is also designed on the front panel of this server, which is not often seen in other rack servers.

Figure 1 front panel area

Unlike a desktop server, the hard disks of most rack servers are pre-mounted and connected to the SCSI controller. SCSI hard disks support online Hot Plug-ins. Currently, manufacturers on the market design a switch for the hard disk when designing rack-mounted servers. We only need to click the switch when detaching the hard disk, after the switch is turned on, the hard disk can be extracted. Remember to ensure that the two sides must be parallel when inserting the hard disk, to avoid problems such as virtual connection, location error and so on, resulting in a server hard disk usage failure.

　　

Figure 2 rack-mounted server hard drive

This rack-mounted server provides two Ultra 320 SCSI interface hard disks. The standard configurations of rack-mounted servers vary with configurations. On the server, because of the high storage performance, ordinary IDE hard disks cannot meet such requirements, while SCSI interface hard disks are compared with IDE hard disks, it has the advantages of faster reading/writing speed, shorter tracing time, and greater data cache. It is widely used in servers. Currently, mainstream SCSI hard disks use the Ultra 320 SCSI interface, it provides an interface transmission speed of 320 Mb/s.

Figure 3 Ultra 320 SCSI interface hard drive

In this rack-mounted server, configured with LG Slimline CD-ROM optical drive, in 1U rack-mounted server, generally use this narrow edge design of the optical drive, because if you are using a common optical drive, it cannot meet the capacity of the chassis.

Figure 4 rack-mounted server Optical Drive

Next let's take a look at the Heart-CPU of this server, as shown in, most of the Rack servers use the design of separating the CPU sink from the fan, the server CPU heat sink usually uses Copper Material with better heat dissipation performance. The R510 G5 adopts the Intel Xeon processor, which can reach the clock speed of MHz. Two turbine CPU fans are configured on the left, from the rack server I saw, we can find that the 1U rack server on the market basically adopts this design.

Figure 5 CPU and fan Area

Open the plexiglass baffle plate in the CPU part, and there are four screws in the four corners of the CPU heat sink for fixing. When unloading, we need to use a screwdriver to pin the screws and then rotate them vertically, until the screw is fully folded. Fold and unload the four screws separately, first gently loosen, check whether the screws have been fully folded out, and then vertically dial out the heat sink (sometimes the heat sink will be glued together with silicon, remember not to forcibly dial ). After removing the heat sink, we can see the Intel Xeon processor.

Figure 6 CPU

As shown in, there are four memory dimm slots on the left side of the CPU. the technical requirements in the server are much higher than those in the general PC memory, we all know that there are two types of memory sold on the market: SDRAM and DDR. The memory has basically been stopped. We can see that these two memory stick is a 184 m ddr memory stick with 512 pins, due to the special nature of the server, generally all rack servers are configured with the Register memory that integrates the Error Checking and Correcting Error Checking and correction functions, this memory stick can detect and correct single-bit errors, greatly improving the server reliability. The memory slots configured for servers of different racks are also different. Lenovo's R510 G5 rack servers provide four slots to expand to 8 GB.

Figure 7 memory slot

In the swap memory, just like the ordinary PC, you just need to switch on both sides, parallel out of the memory.

All devices connected to the main board of the Rack server need power supplies. Next we will introduce the power supply of the Rack server.

From the perspective of security and reliability, power supply is very important in the entire server hardware system. In the market, there are two common computer power sources: the rated power is 300 W and W. Different from the home PC, the equipment that needs power supply on the server is much higher than that of the PC, and a higher power supply is needed to provide power, therefore, rack servers are generally equipped with W power supply.

The larger the power supply, the higher the heat. the two ends of the rack-mounted server power supply are equipped with a fan to provide good heat dissipation performance. We can see from this. This 1U rack server is equipped with a standard power supply. In fact, more than two power supplies are usually configured on rack servers with high and higher configurations, and the power supply supports hot plug-in, prevent the server system from malfunction due to power supply damage.

Figure 8 server Power Supply

Finally, let's take a look at the rear panel of this rack-mounted server. Similar to a common computer, there are power interfaces, graphics interfaces, keyboard and mouse interfaces on the rear panel of the rack-mounted server, generally, servers do not need good graphics display cards. Generally, they all use a motherboard integrated graphics card. Generally, a RS232 interface is required. This interface can be connected to other devices, such as routers and switches, sometimes we may need to use this server to configure the router, then we need to use this RS-232 interface. Generally, the minimum requirement for the server Nic is 10/100 M Adaptive ethernet card. To achieve higher data transmission performance, many servers are equipped with a gigabit Nic, this machine uses two Gigabit NICs integrated with the motherboard.

Figure 9

Summary:

This article introduces rack servers from the perspective of hardware configuration, rack servers on the market may vary in prices, grades, and configurations. Some servers may be different from the ones described in this article, but the basic structure is described in this article, the difference is that the hardware configuration and shape design are different. I believe you will be able to draw a line from each other.