Describes the little-known functions of data center switches.

A vswitch is an important part of a data center. We know that the most important function of a vswitch is to forward data between devices. If you compare devices in a data center to an isolated city, a switch is like a highway between cities. Of course, the highway can be crowded because of heavy traffic, or people may complain because of high charges. It can also cause major losses due to traffic accidents. Similarly, vswitches may encounter these similar problems in the data center. To solve these problems, the functions of data center switches have become increasingly powerful and diversified over the years, ensuring smooth data transmission between devices. However, in addition to the well-known forwarding capacity, port density, and forwarding table items, vswitches also have some little-known functions. Although these functions are only auxiliary functions of the switch, they can add points to the comprehensive capabilities of the switch, which can often determine the choice of a device purchaser. Now let's take a look at them.

CF card

The switch itself has Flash, which can be used to store applications and configurations. The Flash of the early switch is usually 64 MB ~ 256 M. As vswitch applications and configuration files become larger and larger, Flash space is often insufficient. Therefore, some switch designers have moved the implementation of the CF card to the switch, thus greatly expanding the storage space of the switch through the CF card. When you upload an application to a vswitch, you do not need to delete the original application to free up space. You can simply specify the application in the CF card to start. Users can store applications and files on the CF card elsewhere, and then plug the CF card into the switch to complete startup by specifying the application and configuration file in the CF card through the switch. Generally, it is not a problem to store dozens of applications on the CF card. In addition, because the CPU capacity of the switch is relatively weak, it usually takes several minutes to copy an application to Flash, and the copy can be completed in a few seconds through the CF card, the operation time is greatly reduced.

USB Interface

Although the CF card can expand the storage space of the switch, but due to the wide variety of CF card brands, switch adaptation is not realistic, so many low-quality CF cards plug in to the switch, it is easy to cause device operation exceptions, or even restart. Therefore, you should be very careful when using the CF card on the switch. before using it, you 'd better know whether the CF card is a brand specified by the switch manufacturer. If not, it is best not to use it. Some low-quality CF cards may be used several times without any problems, but the next time you can insert a switch for use, the switch may fail. In this case, the failure will not be worth the candle, after all, the switch is several thousand times more expensive than the CF card.

In view of this, with the popularization of USB applications, some switches also implement USB ports. Because the USB interface adopts the standard design and unified interface standards, this avoids brand differences. Whether it is a high-quality USB device or a poor USB device, you must respect such interface standards. USB interfaces are used to detect devices before they are connected. Therefore, USB ports are more and more common in vswitches because they have a higher security factor than the CF card. USB ports can be used to connect USB flash drives, mobile hard drives, and CF cards (using USB interface standards) to other storage devices. This allows you to expand the storage space of switches.

POE

A switch can not only forward data, but also Power other devices. This is the Power on Ethernet function of the switch. A vswitch directly supplies power to the connected device through an Ethernet port. Generally, the power output from a single port can reach 30 W, which is enough to drive an IP phone or Wireless AP. Power Supply for these devices through POE can greatly save the power access of these devices. Generally, a middle-end switch can provide hundreds of Ethernet ports and power supply for hundreds of devices, if the POE function is not available, the power cord needs to be laid for the hundreds of devices. The cost and workload are very large, which is also a waste of space. Therefore, in an application environment with an IP phone or Wireless AP, the POE function becomes the first feature. A switch with such a function has a competitive advantage.

Display

Data center O & M personnel often perform routine checks on various devices, especially switches, to detect potential operation risks in a timely manner. However, every time you check the switch, you need to use a computer to access the network or the device to perform operations on the device, which is very inconvenient. It cannot be carried without a data cable or a computer check. Frequent inserting of serial lines and network cables to the vswitch is not safe, which may cause static electricity. Therefore, some switches have added the display function. The operation parameters of the switch can be directly seen through the display screen, and buttons on the display screen or touch screen can be used to operate the switch. With the display screen, O & M personnel can directly check the switch through the display screen, which is very convenient to use. When a switch is not running normally, such as being attacked by a network, and the hardware of the device fails, when the switch cannot be controlled through the data cable, the device can still be operated through the display screen, keep abreast of device operation exceptions and check the operation history of the device to eliminate faults as soon as possible. Therefore, when a switch fails, the display screen is an indispensable helper. Although the display screen has so many advantages, not all switches have them, and the technical implementation is not difficult. However, adding such a display will increase the cost. Therefore, only high-end switches can have a display screen.

Wide Temperature

Most people are impressed by the fact that switches are placed in data centers with excellent environments. In the dark shaft of the building, on the train, on the power transport, there are them in the cold outdoor. Vswitches also have family members with strong adaptability, such as industrial switches and wide-temperature switches, which can work normally in harsh environments. They are more capable than switches working in greenhouses. Cisco has put their switches in space for use, so it can be seen that switches are everywhere. The wide temperature indicates that the switch can work in an environment with a greater temperature range. Generally, the switch operating temperature is 0 ℃ ~ 45 ℃, while the operating temperature of the Wide-temperature switch can reach-40 ℃ ~ 70 deg C. This allows the switch to work in a wider environment.

The features few mentioned above enrich the features of vswitch products, allowing more vswitches to facilitate data center maintenance. Whether it is a CF card or USB card for resizing storage capacity, whether it is a convenient O & m poe or display screen, these functions fully reflect the wisdom of switch designers. With the call for building a new generation of data centers, switches, as an important component, are bound to design more rich functions to build a new generation of data centers.