Thank you for your help.

I have solved the problem. Like you said, I used the IPv6.

I still don't want to add IPv6 to the whitelist. Because, in our organization, we just beginning to survey IPv6 network system.
If the IPv6 network system is ready. I will
 add our IPv6 address to the whitelist as soon as I can.

At last, I am very thank you for solving my question.

Anssi Johansson <avij@centosproject.org> 於 2018年7月20日 週五 下午11:05寫道:
韋佳均 kirjoitti 20.7.2018 klo 17.56:
> To whom it may concern
>
> I am a new system administrator fromlinux.cs.nctu.edu.tw
> <http://linux.cs.nctu.edu.tw/>(centos.cs.nctu.edu.tw
> <http://centos.cs.nctu.edu.tw/>)
>
> And I want to sync the centos package from msync.centos.org
> <http://msync.centos.org/>
> but I got the error message
>
>     @ERROR: Unknown module 'CentOS'
>     rsync error: error starting client-server protocol (code 5) at
>     main.c(1657) [Receiver=3.1.3]
>
>
> I search from google, And I find the message
> http://grokbase.com/t/centos/centos-mirror/149ka8ehsy/cant-rsync-from-msync-centos-org-centos
>
> So, I think I must to check our machine is in white list.
> My machine IP is "140.113.168.126"
>
> If IP is not current, may I update the information.
> Sync schedule: Every 6 hrs
> Bandwidth: 1Gbps
> Location: Asia Taiwan
> Sponsor: Computer Science Computer Center, National Chiao Tung University
> Sponsor URL: https://www.cs.nctu.edu.tw/cchonor/
> IPv4 address to authorize: 140.113.168.126
> IPv6 address to authorize: -
> Email contact: weicc@cs.nctu.edu.tw <mailto:weicc@cs.nctu.edu.tw>
> Mirroring AltArch  : not yet

We seem to have 140.113.168.126 enabled already. Perhaps your server has
an IPv6 address? Does rsync work better if you use the -4 option to
force the use of IPv4?

If this is the case, I'd prefer to add your IPv6 address to the
whitelist as well so you would not need to sync over a legacy protocol.

This would be a good way to determine your IPv6 address:

$ rsync -6 rsync://no-access.miuku.net/keep-out
@ERROR: access denied to keep-out from yourhostname (2001:db0::123)

(the error message shows your IPv6 address, if you have one)
_______________________________________________
CentOS-mirror mailing list
CentOS-mirror@centos.org
https://lists.centos.org/mailman/listinfo/centos-mirror


--
Sincerely,
Kevin Wei (weicc) 韋佳均 (Wei Chia-Chun)
Computer Science Computer Center, National Chiao Tung University
1001 University Road, Hsinchu, Taiwan 300, ROC
+886-3-5712121 #54707