【 Weak current College 】 CiscoIOS software troubleshooting methods---Power By 【 China power house network 】

In fact, routers and switches and other network devices and is also a computer, it can also be divided into two parts of the hardware and software. Ordinary PC host operating system (e.g. Windows) in use there will be problems, router or switch operating system (such as Cisco's IOS) is no exception.　　As the network administrator must also have trouble running IOS Software excluded. Here the author is on common failures and solutions do some examples to help network administrators troubleshoot network problems. 1. boot configuration file is missing Windows operating system is started will view the host in the boot.ini file to determine the boot sequence. When the configuration file is corrupted, the operating system fails to start. You need to use tools such as the disc on the restoration of the configuration file. Routers also have similar a configuration file. If the router is started, the IOS system will look for the configuration file boot system statement. This statement determines the router which images start IOS software.　　Sometimes this statement configuration error, it will cause the router boot problems. Experience this issue after how to resolve?, referring to the specific measures, the author is necessary first of all, to clarify the IOS software image problems. Cisco IOS software devices tend to have three different run-time environment, namely RomMonitro, Boot Rom and Cisoco IOS. Router in start time, according to user instructions select an environment for running. Specific operating environment that is in the configuration file of the Boot System specified in the statement. Here it is important to note that the three types of run-time environment does not mean a different operating system. If the Microsoft operating system as an example, here is the run-time environment does not like its XP, 2003, and so on represent different operating system. But more like a startup, press F8 to start mode selection interface. System administrator, and then inthe event of system failure, tend to press F8 to select specific startup mode to solve the problem.　　If the resolution of problems encountered when using VGA mode to troubleshoot. In fact, IOS three working environment with the operating system startup mode is similar. If the ROM Monitor work environment, mainly provides a lower level of functionality and diagnosis. As in the work environment can be used to repair a system failure or a password recovery. But in the BootRom mode, only to be able to use IOS software features a limited subset.　　Both work environment with a Microsoft operating system security model is similar to functionality will be greatly restricted. To this end, the two work environments are often only used to complete the particular maintenance task. When a network administrator to find routers work environment is not, as some functional restrictions. You need to consider whether it is the Boot configuration System statement is incorrect.　　A relatively simple method of identification is through Show Version statement to view the router running specific work mode, as shown in the figure below: in this graph, the bottom row displays the current operating environment. When it finds the work environment has problems, you need to reconfigure the Boot System statement, choose the right working environment. Second, register configuration error IOS operating system storage where? for Cisco products, it can be stored in multiple places. Such as Flash memory TFTF servers, and so on. Do a figuratively, as if in the same host more than one installed on the same version of operating system, just install partition. But more than one partition operating system independent of each other, such as different extents in the operating systems their desktop configuration may be different. As long as there are no errors starting the configuration file, the user can select their favorite any one operating system to start. But if there is a problem with this configurationfile, such as boot sequence problem, what results?　　if it wants to adopt the D disk partition operating system because the system from their personalized settings. However, due to configuration problem, C disk partition operating system selected as the preferred operating system, the results of the last system used by the operating system to be a problem. In IOS. Wrong registers configuration causes ISO software from Flash memory in the correct load ISO software. Configuration registers like Boot.ini configuration file tells the router IOS from where to get the software image (that is, from where to start). Similarly, the wrong startup might give a fatal failure network.　　IOS software image as now exists in two places, but the two parts of the configuration file or IOS versions. After the restart, if you choose IOS software image has errors, it will cause network access or network conflicts, etc. But the discovery configuration registers when the error occurred, it can still use the Show Version command configuration registers to final confirmation. The following illustration: System Image that represents the image storage location.