ipchains and ntp udp port 123

From: Robert Lomitola (ralnw6@bellsouth.net)
Date: 06/17/02 

From: Robert Lomitola <ralnw6@bellsouth.net>
Date: Mon, 17 Jun 2002 16:13:16 -0400

I have a redhat72 machine used as a gateway that I am trying to get ntpd
to work. The message log shows the firewall deny the packets from
time.nist.gov at 192.43.244.18:123 on the ppp0 interface. i have tried
ipchains -A input -p udp -i ppp0 -s 192.43.244.0/24 123 -j ACCEPT

Then I did a ipchains-save >/home/xyz/ipchains.rules
I then inserted this line
-A input -s 192.43.244.0/255.255.255.0 123:123 -d 0.0.0.0/0.0.0.0 -i
ppp0 -p 17 -j ACCEPT

into the /etc/sysconfig/ipchains file above this line
-A input -s 0/0 -d 0/0 -p udp -j REJECT

I also tried directly editing the ipchains file with
-A input -s 192.43.244.18 123 -d 0/0 -p udp -j ACCEPT

If I turn off the ipchains service briefly I can successfully run
ntpdate time.nist.gov and I sync up with the time server otherwise
it doesn't work. High security option was selected during the
installation and the server is patched up to date.

Best regards,

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