Hi folks,

I am having some interesting issues with the newer implementation of ntp 4.2 versus 4.1.

Ok, trying to configure a local timeserver on my network (with both public and private subnets) that sync's from the public ntp pool and/or other stratum 1 and 2 public timeservers, which then other machines on my network will use as their timeserver, however since my internet connection is not the fastest, not to mention I have other uses for it, I don't want to allow open access to my timeserver.

Now under 4.1 here is what my primary timeserver's ntp.conf looked like (where 1.2.3.4 and 5.6.7.8 are subnets I want to allow to use my timeserver):

server timeserver1.somedomain.com
server timeserver2.somedomain.com
server timeserver3.somedomain.com
server timeserver4.somedomain.com
server timeserver5.somedomain.com

driftfile /var/db/ntp.drift

restrict default noserve notrap nomodify
restrict 1.2.3.4 mask 255.255.255.248 nomodify notrap
restrict 5.6.7.8 mask 255.255.255.248 nomodify notrap
restrict 127.0.0.1

Now this configuration does not work under 4.2, and from what I can gather from the documentation, this is on purpose, and under the new rules, you have to add a explicit "restrict" line for each server entry.

And from my testing this seems to be true, restrict defaults of "noserve" and/or "ignore" block sync with the previous listed timeservers unless I eliminate the restrict entries altogether, or specifically list the each server entries IP address with its own restrict line.

The problem is that you can't use hostnames in a restrict line, and the reason we use hostname on server lines is so a hosting party can move the time service to a different IP address with out disrupting timeservice, not to mention for obvious reasons specific IP listings won't work if you want to use the ntp.org ntp server pools. So if you want to sync with pool timeservers and/or use only host names to sync with specific public timeservers you have to allow open access to your time server?

So is this the way it is supposed to work? am I making a stupid mistake? or is this a bug in 4.2?

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