錯誤提示：
There are unfinished transactions remaining. You might consider running yum-complete-transaction, or "yum-complete-transaction --cleanup-only" and "yum history redo last", first to finish them. If those don't work you'll have to try removing/installing packages by hand (maybe package-cleanup can help).
這種情況是由於在使用yum安裝東西的時候，強制退出yum或者yum異常退出造成的，再次使用yum時就會提示上述的錯誤：
解決：
1、安裝yum-complete-transaction，這個工具是在yum-utils這個包里面，所以，需要先安裝yum-utils才能使用yum-complete-transaction
# yum -y install yum-utils
2、清理緩存
# yum clean all
3、執行清理未完成事物
# yum-complete-transaction --cleanup-only