According to an example, a method includes: before a first process exits, a kernel receives a connection holding request carrying a File Descriptor (FD) transmitted by the first process, with respect to the FD carried by the connection holding request, the kernel increases a reference count of a file object corresponding to the FD and puts the file object into a cache, the kernel returns cache position information to the first process, such that the first process puts a corresponding relationship between the cache position information and identifier information of a communication connection pointed to by the FD in a predefined storage area; when a second process starts, the kernel receives an FD obtaining request carrying the cache position information transmitted by the second process, reads the file object from the cache, assigns a new FD to the file object and returns the new FD to the second process.