RE: Firewalled NTP on Redhat - ntpdate works, but ntpq doesn't

Good info, but does ntpq use different ports than ntpdate? After all, ntpdate works, but ntpq does not.

-----Original Message-----
From: redhat-list-bounces@xxxxxxxxxx [mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of Herta Van den Eynde
Sent: Friday, May 18, 2007 2:58 PM
To: General Red Hat Linux discussion list
Subject: Re: Firewalled NTP on Redhat - ntpdate works, but ntpq doesn't

On 18/05/07, Young, Mike <Mike.Young@xxxxxxxxxxxxxx> wrote:
Hello,

I'm seeing an odd NTP problem on a couple of Redhat servers here. Basically the NTP client is on a firewalled DMZ, away from the NTP server. NTP updates via ntpq work fine on the local NTP server subnet, but it isn't working for hosts on the firewalled DMZ. We've checked ports on the firewall, and 123/UDP is open. In addition, we see packets incrementing when we use the "iostat" command in ntpdc, and don't see any dropped or ignored packets in iostat either.

Any ideas?

Thanks,
Mike.

The ntp server uses 123/UDP, the client use ports above 1023.
http://www.unix.org.ua/orelly/networking/firewall/ch08_13.htm suggests
setting up an ntp server on your DMZ.

Kind regards,

Herta

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