Subject: Re: Poor timekeeping on x86 smp branch?
To: None <,>
From: Sean Doran <>
List: tech-smp
Date: 04/23/2002 19:22:20
[Steve Bellovin notes that ntpd does not adapt to changes
in local or (some) remote IP addresses]

The evil history of xntpd involved forking off a client which
would do DNS lookups and use xntpdc calls to configure the parent.

Dennis hacks are fun. :-)

Unfortunately, this is yet another case where overloading 
IP addresses both as peernames and addresses for routing
purposes sux.  :-(

I believe one could do a further ugly hack and wrap ntpdc in a
client that checks for changes in DNS name->address mappings and
for changes in local addresses.   While this should work for machines
which use only server declarations, changes in local addresses may
be complicated by (remote) access lists and symmetrical peering
declarations, alas.  Therefore, an even better fix may be to use
ntp keys to identify the correct peer/server/...  independent of
not only IP address but choice of IP protocol.   That would take
considerable work, poses a deployment problem, and is not obviously
best undertaken just for NetBSD.