Nov 7 12:16:19 host-10-101-0-10 sendmail[1098]: My unqualified host name (host-10-101-0-10) unknown; sleeping for retry
Nov 7 12:17:19 host-10-101-0-10 sendmail[1098]: unable to qualify my own domain name (host-10-101-0-10) -- using short name
/var/log/maillog에 찍히는 에러 메세지
/etc/hosts에 현재 사용중인 호스트명 추가해주면 됨[root@host-10-101-0-10 ~]# hostname
host-10-101-0-10
[root@host-10-101-0-10 ~]# cat /etc/hosts
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4 host-10-101-0-10
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6 host-10-101-0-1