Earch And Implementation Of Embedded Network Equipment Online Hot-patch

Providing high availability networking facilities is one of the pursuit goals of the equipment manufacturers. However, during the progression of the routine maintenance of the machine, we have to face to the problem of system application software upgrading continuously, because of the software’s flaws and adding new features. In traditional way of upgrading, we need to load new version image and reboot the system or processes. Then, the equipment is in a certain condition of working abnormal, it will have much affection in service.Through analysis and study of software’s upgrade process run on network system, a online hot-upgrade method base on Linux operation system is present in this paper. This method can download patches via internet automatically, and can upgrade system software without rebooting the system or process. So, this method can make sure the equipment run continuously while patches downloading and software upgrading, which ensures networks equipments keep working and have no affection to its service while upgrading. Online hot-upgrade method in this article can be divided into two modules:First one is patch download module, it can download patches through network; and second one is hot-upgrade module, it can modify some partial problem of software while system is in service.Patch download module’s major function is upgrade process run on local equipment downloads the patches from patch server automatically. Internet programming technique is used in this part.Hot-patch module’s major function is upgrade process can pause target user process directly, and rewrite a jump code at the entry address in memory of target function in target process, so as to associate target function with patch function. Then resume the target process and finish the patching process.This article makes an analysis of online hot-upgrade technique, tells the background and current situations of this study, and reflect its advantages through comparing to other upgrade methods. Then, offer the design methods for every module and sub-module with synthesizing these detail functions on Linux system, and develop and realize the system module using the technologies like internet programming and Linux kernel. Next, an analysis of the experiment result is given and make a summary of this article.The result shows that online hot-upgrade can improve the availability and extensibility of network equipment application software effectively. This method is of high maneuverability and has the actual application value, and meet HA requirements of CGL standard, which is about carrier Linux standard released by OSDL.