[ntp:hackers] Re: Config file format

Paul Vixie paul at vix.com
Mon Feb 21 12:51:26 PST 2005

> >So if we forget how the config gets to the daemon for a moment and look
> >at the file format - what's the collective wisdom on my suggestion to
> >use the same syntax as isc dhcpd?  

i'd like to add some history here.  isc dhcpd's config syntax was loosely
patterned after bind8/bind9's, which was loosely patterned after gated's.
(i had been a long time user of gated at the time i designed bind8's config,
and the author of isc dhcpd thought that bind8's config style was an isc
company guideline, which it wasn't at the time but now sort-of-is.)  i note
with some amusement that noone inside of juniper or outside knows whether
the junos config language was patterned after gated, bind8, or isc dhcp.

> Can I make a pitch here ?
> I'm very much in favour of config files and interactive tools using
> the same commands, sort of the way cisco routers do it.

this is also how decnet NCL worked.  it has some positive aspects to it,
but it's still order-dependent, and making changes by prefacing a command
with "NO" (to get rid of the old one) and then entering a new one and
hoping that your context is correct... blows.

> Being consistent this way is much easier for the administrator and
> requires a lot less documentation.  Today we have three different
> syntax'es for "use this NTP server", one for ntp.conf, one for ntpq(8)
> and one for ntpdc(8).
> The hierarchy style of config files (like named and dhcpd) doesn't
> lend itself easily to such a concept, but is the only way to sensibly
> handle configuration files which are thousands of lines long.
> On the other hand, the average ntpd config file is less than 10
> lines long, so we should not need to put a big and complex hierarchy
> on it.

on a juniper, the command language can incrementally edit the config, but
the config can also be uploaded and downloaded, which is good for rancid.

i havn't tasted anything else that's nearly as good.  i wish bind worked
this way, and someday i hope that it will.

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