Bug#391841: debian-policy: Remove time-daemon
On Sat, Dec 12, 2009 at 09:58:24AM -0300, Dererk wrote:
>
> I consider that the description is both, relatively generic and straight
> forward to a function or service, which in my opinion, in this case is
> the main goal.
The problem I have with alot of virtual packages is what you
can expect from such a virtual package. Some of them are
very clear in what you can expect, but others are not.
It currently just says "anything that serves as a time daemon".
I can for instance interpret that as a daemon that just tells
you what the current time is, like the daytime or time service.
It's part of most inetd implementation, but ussually not
enabled by default. It will not change the local clock,
just tell you the current time.
Someone else might want to have something that can keep it's
clock more or less at the correct time, but doesn't need it
to be a daemon. There are several programs that can do that like
adjtimex, hwclock, chrony and probably some others that
compensate for the drift of your clock by having 2 measurements
and setting the kernel kernel to compensate for that.
Others might need something to have all computers in their
network to agree on the time. For instance Kerberos needs
them to agree on the time, but it doesn't care that it's the
correct time. This can be done by ntp by setting 1 server to
redistribute it's local clock and let all others sync to that,
but requires manual configuration.
Depending on ntp does not garantee you anything. The computer
might not be in a network, or it might be but might not have
access to external ntp servers.
On a related note we currently have this in the init script info
section:
# Provides: ntp
So packages that now depends on ntp | time-daemon and there is
something else that provides time-daemon installed, and the
package has a Required-Start: ntp in the init script it
probably broken unless that other package also provides ntp.
And ntp currently does not sync the clock at start, it ussually
takes about 3 minutes for it to set the time for the first time.
There is a program ntp-wait you could use to wait for that,
but you probably don't want to wait that long before starting
your service.
If you have that installed on your laptop, and you currently don't
have network connectivity you probably also don't want to wait
until that times out before you can log in.
Kurt
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