an existing software needs to be installed. During the installation process, it has been reported that a nss-util dependency package cannot be downloaded, and the installation process is terminated. I tried to change the source and it didn"t work, so I downloaded it manually and uploaded it to the / var/cache/yum/ directory, and then I couldn"t perform the installation. During the installation, I still downloaded it through wget, and if I couldn"t download it, it was interrupted