리눅스 ntpdate: no server suitable for synchronization found

no server suitable for synchronization found

1 문제상황[ | ]

성공

[root@zetaweb ~]# ntpdate time.bora.net
 2 Mar 01:39:58 ntpdate[26656]: adjust time server 203.248.240.140 offset 0.013493 sec

실패

[root@zetaweb ~]# ntpdate ntp.kornet.net
 2 Mar 01:47:16 ntpdate[26704]: no server suitable for synchronization found
[root@zetaweb ~]# ntpdate pool.ntp.org
 2 Mar 01:46:59 ntpdate[26702]: no server suitable for synchronization found
[root@zetaweb ~]# ntpdate time.nist.gov
 2 Mar 01:47:53 ntpdate[26709]: no server suitable for synchronization found
[root@zetaweb ~]# ntpdate time.windows.com
 2 Mar 01:47:23 ntpdate[26705]: no server suitable for synchronization found

2 37 포트 확인[ | ]

[root@zetaweb ~]# nc -z time.bora.net 37 -w2
Connection to time.bora.net 37 port [tcp/time] succeeded!
[root@zetaweb ~]# nc -z time.nist.gov 37 -w2
Connection to time.nist.gov 37 port [tcp/time] succeeded!

[root@zetaweb ~]# nc -z ntp.kornet.net 37 -w2
[root@zetaweb ~]# nc -z pool.ntp.org 37 -w2
[root@zetaweb ~]# nc -z time.windows.com 37 -w2

3 참고[ | ]