A solution to hardware fault of router

Perhaps because many administrators are unfamiliar with the router or understand the reasons for not in-depth, a large number of router hardware failures appear on the software, the following we mainly analyze several common router hardware failures.





Router hardware failure is the problem we often encounter, here we mainly analyze the router hardware fault resolution, routers compared to hubs and switches, it may be a little unfamiliar to everyone. Because many small LANs use proxy servers or software routes, few dedicated hardware routers are used. However, with the rapid development of local area network, the application of routers in LAN is increasing gradually, and the hardware faults of various routers follow.





from the previous introduction we learned that routers are like computers made up of hardware and software, and of course the problem can be found in hardware and software. Perhaps because many administrators are unfamiliar with the router or understand the reasons for not in-depth, a large part of the router hardware failures appear on the software. The author sums up the following kinds of fault classification to facilitate the readers to be disabled.





1 Router hardware failure




The hardware for the
router includes Ram/dram, NVRAM, FLASH, ROM, CPU, various ports, and motherboard and power supplies. Router hardware failures can generally be seen from the LED indicator. For example: There is a green PWR (or power) status indicator on the supply module. When the indicator light is on, the power supply is working properly. The online and offline LEDs on the interface module and the TX, RX LEDs. The RX LED is green to indicate that the port is receiving a packet, and if Orange, a packet that is receiving flow control. The TX light is green to indicate that the port is sending a packet, and if it is orange, a packet that is sending flow control. Different routers have different lights to indicate different meanings, so you'd better read the instructions first.





Router hardware failures can sometimes be detected from the boot log or in the configuration process. Since the router starts with a hardware power self-test, running the hardware detection program in ROM to detect whether the components are working properly. The initialization of the software begins only after hardware detection has been completed. If the router detects a router hardware failure at boot time, it will be logged in the system's startup log for later inspection. If you are configuring a router, when you enter a port configuration, the system has been the error, it may be the problem of the port. In addition, we must do a good job in the construction of the router environment, such as: Lightning protection grounding and stable power supply, indoor temperature, indoor humidity, electromagnetic interference, anti-static, etc., to eliminate all possible potential trouble.





2) system lost





here refers to iOS (Internetworkoperatingsystem), which is the basis for all the configuration of the router-the operating system. It is stored in flash, sometimes due to operational errors or other unpredictable reasons (such as sudden power outages), resulting in Flash iOS lost, resulting in the router does not start properly. When this happens, you can also use the backup operating system software that is saved in ROM, which is typically a bit lower than the iOS version in Flash, but enough for the router to start and work. In order for the router to work properly, you must download the new iOS to flash again. If the flash space is large enough, you can also save multiple iOS software and choose which version of the system to use. To be able to recover quickly after such a failure, it is best to keep the iOS software in a secure server for urgent needs.





3) System defect





Like Windows systems that are often plagued by viruses, iOS's system flaws can cripple routers, for example: The red code has restarted some of the famous brand's routers. iOS also has a security flaw, if not upgraded in time, malicious people will use your router as his target. With the development of routers, some routers now have the function of automatic defensive attack, such as defending against Dos attacks, preventing password guessing and so on. The system flaws in iOS are typically not patched by patches, but instead replaced by new iOS. Once a system bug is discovered, the router vendor publishes bugs, affected systems, and the corresponding new iOS software on the site in a timely fashion, and you must choose the version that is appropriate for your router model. Cisco has said that they will use the "0 fault" high-end router software, it can eliminate the circuit or human factors caused by the loss of data or information, even if there are errors, packets can still be forwarded down, so that the network can prevent the router hardware failure, which will reduce the burden of NMS.





4) Password loss




The password in the
router has two places to set up. As you can see from the previous introduction, there are two basic access modes to access the router: User mode and administrative mode. For security reasons, you need to set a password when entering both modes. Although everyone knows that the password is the key to the Administrator with the greatest authority, someone will forget it. Even the password that someone has set is too simple to be hacked into and changed the password. In fact, as long as we are more careful, these low-level errors can be avoided. If the password is lost, don't be afraid, because the router provides a password recovery method. In addition to the two basic access modes (user mode and administrative mode), the router also has a rxboot mode, which allows easy recovery of the router password in this mode. Of course, only the computer through the console port to establish a super terminal connection before entering. Also some routers in the panel provides more convenient reset keys, as long as reset several times, you can restore the original password.





5) Profile loss





This is also a frequently occurring router hardware failure. Let's start by looking at the router's startup process:





(1) System hardware power self test. Run the hardware detection program in ROM to detect whether the components are working properly. After hardware detection is complete, the next step is reached.





(2) runs the bootstrap boot program in ROM.





(3) Find and load iOS system files





(4) iOS loaded, the system first searches the NVRAM for the saved Startup-config file, the system configuration. If there is a startup-config file in the NVRAM, the file is transferred into RAM and executed article by article. Then, according to the commands in the configuration file interface address settings, routing processing and so on. If the Startup-config file is not successfully booted, the system enters Setup mode and the initial configuration of the router is done by man-machine conversation.