How to configure NTP server on ASA using hostname

Unanswered Question
Apr 16th, 2009

Is this forum alive? I'd rather say all real network pros abandoned it.

Can someone please tell me how to configure the ASA with NTP server hostnames. I want to explicitly use hostnames as a particular NTP hostname is actually a pool of hosts with different IP addresses. One of them goes down the other one takes over.

ASA(config)# ntp server ?

configure mode commands/options:

Hostname or A.B.C.D IP address of peer

I'm trying to use Hostname and fail.

ASA(config)# ntp server


ERROR: % Invalid Hostname

DNS is enabled and I can resolve this hostname into the IP address:

ASA(config)# ping inside

Type escape sequence to abort.

Sending 5, 100-byte ICMP Echos to, timeout is 2 seconds:

I have this problem too.
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Collin Clark Thu, 04/16/2009 - 13:13

Unfortunately the lookup is done locally and not via DNS.

<font size="2"></p><p>fw-1(config)# ntp server</p><p>                                 ^</p><p>ERROR: % Invalid Hostname</p><p></font>

But once you add the hostname locally, it works. Also note that the hostname must start with a letter!

<font size="2"></p><p>fw-1(config)# name  </p><p>fw-1(config)# ntp server </p><p></font>

Hope that helps.

zheka_pefti Thu, 04/16/2009 - 13:17

Thanks, Collin. It would work like a charm but the original idea was to use a hostname for a pool of NTP servers and this pool consists of a number of hosts that could be changed without a notice.


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