[ntp:questions] Number of sockets in NTP
mayer at ntp.isc.org
Fri Jul 4 16:02:27 UTC 2008
Kiran Shirol wrote:
> I am wondering why do we need to open one socket per interface in the
> In a very large setups with huge number of interfaces, NTP can potentially
> open large number
> of sockets. What is the motive and the advantages of opening one socket per
> interface ?
> Can we not do away with just the wildcard sockets ?
No, it not as simple as that. Because NTP uses UDP there is no
previously established connection to respond on. There are a number of
other reasons to avoid using wildcards, including autokey and firewalls
which expect responses to packets from the same address to which the
outgoing packet was sent.
There is code that will allow you to specify which IP addresses to open
and which to send queries out on but it's not yet available while we
resolve some configuration questions. See
http://support.ntp.org/bin/view/Dev/NtpdAndNetworkSockets for what we
are looking at doing.
Note that this issue has been extensively discussed and you should find
them in the archives.
More information about the questions