求助sendmail问题!
[root@server-linux mail]# tail /var/log/maillog
Jul 14 14:04:46 server-linux sendmail[3145]: gethostbyaddr(192.168.1.21) failed: 1
Jul 14 14:04:46 server-linux sendmail[3146]: starting daemon (8.13.7): queueing@01:00:00
错误入下,请教这个是怎么回事呀?