Gui for configuring NTP

Tim ignored_mailbox at yahoo.com.au
Sat Dec 10 05:33:28 UTC 2005


On Fri, 2005-12-09 at 17:42 -0500, Gene Heskett wrote:
> One really should be using pool.ntp.org, which is a round robin
> dynamic assignment, giving ntpd 3 servers to have as a choice of peer.

I've found that using "pool.ntp.org" usually means that I keep on using
the same set of NTP servers (i.e. no round-robin behaviour).  I found
you needed to be a bit more specific in specifying different pool server
addresses to get different servers.

e.g.  server 0.pool.ntp.org iburst
      server 1.pool.ntp.org iburst
      server 2.pool.ntp.org iburst

If you experiment around, you notice that one of numerical sub-domain
prefixes is the same as just pool.ntp.org, and they all seem to produce
the same results for each query (e.g. what's listed as the first IP for
0.pool.ntp.org is always listed as the first IP, and the NTP client will
keep on using the first answer).

And you really need more than three servers, in case you get some that
don't respond (I frequently find two don't respond) or agree with each
other (if one is different, how do you know that the other two aren't
wrong, even if they agree with each other).

As well as the above, more general, pool.ntp.org servers, I added a
couple of supposedly local ones.  Since I'm in Australia, I picked the
au.pool.ntp.org and nz.pool.ntp.org servers, and my ISP's own NTP
server, giving me five different servers.

I also wiped out the /etc/ntp/step-tickers and /etc/ntp/ntpservers files
as they seemed to cause NTP to not work according to how I wanted it
configured.  DHCP assigned NTP server addresses muddy things, as well.

-- 
Don't send private replies to my address, the mailbox is ignored.
I read messages from the public lists.




More information about the fedora-list mailing list