ntpsec | "ntpq -c ifstats" asking for a keyid (#298)

[Hal Murray]

> Well, I might bite if ntpd could be reconfigured by sending it a USR1 or
> USR2 signal, but a complete restart doesn't sound that appealing to me. 

USR1 and USR2 are already used to bump the debug level up/down.

SIGHUP is used to reopen the log file (after logrotate) and reread the leap 
file if it has changed.  It could be extended to reread the keys file and/or 
ntp.conf

leap and keys are "simple" - there is only a simple data structure that is 
easy to update.

Updating ntp.conf on the fly is more complicated.  There is already an 
internal parsed version.  I think it would be reasonable to parse the new 
config then diff them and apply the differences.

Is the list of server (peers) the only internal structure that is not simple 
to update?

Eric: Reloading ntp.conf should be added to your list.  keys too.


> Restricting configuration to the localhost interface by default might be a
> saner approach. 

Mostly, I was looking for something that was simple and clean.  Low tech.

Suppose you were running a bank,  How often would you change your config file?

On the other hand, if something goes wrong, being able to fiddle with the 
config could help debug things and/or restore service.

-- 
These are my opinions.  I hate spam.