to resolve the hostname every 60 seconds
fixes ntpd invocations before e. g. a dialup link is established and such.
as we want ntpd to be a "fire and forget" background daemon it should
cope with such situations.
tested by many
which, besides the head pointer for the list of course, stores the original
address as specified (i. e. as hostname instead of resolved IPs) and flags
and such.
1) base the interval calculation on the offset from the last reply, not
from the last peer update.
Allows us to send more queries again faster when the local clock
diverges too much
2) every time we form a peer update (for which we need 8 replies)
check wether we have a ready peer update for all peers that are
currently trusted, and if so, calculate the total offset and call
adjtime().
that means that adjtime is no longer called in fixed intervals
but whenever we have enough data to reliably calculate the local
clock offset.
In practice, that means we call adjtime() less often, but with
probably better data.
3) invalidate peer updates after beeing used. no point in re-using them
- this resulted in calling adjtime() multiple times with the same
offset, which doesn't make sense
tested by many
a close-to-reality stratum, a real reference time, and a leap indicator
that will indicate if the local clock isn't synchronized.
This also means that until the server feels it's synchronized, it will
tell the clients it isn't. This is normal, and correct.
ok henning@
we know have both a "server" and "servers" keyword. they differ when the
hostname resolves to more than one IP, server picks one and servers expands
to all.
that means no longer stuffing a sockaddr_storage into ntp_peer but a pointer
to a linked list of ntp_addr structs.
in the "servers" case the list of n addresses returned by host() is expanded
into n ntp_peer structs and thus n individual peers.
in the "server" case the whole list is attached to ntp_peer, and whenever we
do not receive a reply in time we traverse the list one further, so that
hosts with both AAAA and A records are first tried with the AAAA one but
we gracefully fall back to the A one.
semantics with theo; hacked up on the Montreal->Frankfurt flight.
again Air Canada surprised me, that older 767 hat pretty decent seats.
henning