systemctl?restart?sendmail.service Job?for?sendmail.service?failed?because?a?timeout?was?exceeded.?See?"systemctl?status?sendmail.service"?and?"journalctl?-xe"?for?details.在centos7上面重啟sendmail服務器，出現(xiàn)這樣的問題。。。怎么解決??？求大佬指點