Re: Mandriva: Can't connect to ANY NTP server - Why?

From: Enrique Perez-Terron (enrio_at_online.no)
Date: 11/26/05 

Date: Sat, 26 Nov 2005 21:47:06 +0100

On Sat, 26 Nov 2005 17:18:36 +0100, Michael Badt <mibadt@gmail.com> wrote:

> Thanks all,
> I've verified that my gw doesn't block port 123.
> Yet still I can't find any servers.
>
> Any idea?
>
> Here's the output from both commands (as root):
> =========
> [root@Atlantis miki]# /usr/sbin/ntpdate time-a.nist.gov
> Looking for host time-a.nist.gov and service ntp
> host found : 1.0.0.0

But what is this? Host 1.0.0.0 ???? This looks like there is something
very wrong with the host name resolution.

Time-a.nist.gov has address 129.6.15.28.

> 26 Nov 18:15:29 ntpdate[11138]: no server suitable for synchronization found
> [root@Atlantis miki]#
> [root@Atlantis miki]# /usr/sbin/ntpdate -u us.pool.ntp.org
> Looking for host us.pool.ntp.org and service ntp
> host found : 1.0.0.0

What? Address 1.0.0.0 again? Very recently in this or another newsgroup,
someone had this address showing up, but I wasn't able to find back to it.

Anyway, us.pool-ntp.org has a bunch of addresses:

  $ dig us.pool-ntp.org
  [...]
  ;; ANSWER SECTION:
  us.pool.ntp.org. 1500 IN A 24.34.79.42
  us.pool.ntp.org. 1500 IN A 65.19.139.44
  us.pool.ntp.org. 1500 IN A 65.75.183.220
  us.pool.ntp.org. 1500 IN A 66.115.136.4
  us.pool.ntp.org. 1500 IN A 67.64.199.49
  us.pool.ntp.org. 1500 IN A 67.159.5.116
  us.pool.ntp.org. 1500 IN A 72.25.72.228
  us.pool.ntp.org. 1500 IN A 204.17.42.199
  us.pool.ntp.org. 1500 IN A 207.145.113.115
  us.pool.ntp.org. 1500 IN A 208.201.242.2
  us.pool.ntp.org. 1500 IN A 209.237.225.10
  us.pool.ntp.org. 1500 IN A 217.160.252.229
  [...]

What output do you get from name resolution commands like "dig",
or "host"? What address is shown in the output from "ping"? Here
is mine:

  $ ping us.pool.ntp.org
  PING us.pool.ntp.org (217.160.252.229) 56(84) bytes of data.

Unless you get something valid here, forget about ntp problems, you
have a name resolution problem. Notice that dig/host may be doing
its things differently from "ping". I presume ntpd and ntpdate use
the "gethostbyname()" function, which is probably what "ping" also
does. Therefore, "ping" is probably the most telling here.

> 26 Nov 18:16:18 ntpdate[11145]: no server suitable for synchronization found

-Enrique

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