named not listening at all - was Re: named is listening on wrong device

[Jim Reid]

>>>>> ">" == D Stussy <kd6lvw at bde-arc.ampr.org> writes:

    >> I like to start all my servers first (just to give them low
    >> process numbers - look's neat).  Then I define the interfaces
    >> (via "ipconfig").  "GateD" has no problem finding that I have
    >> brought up an interface (it's found within a few seconds of
    >> being up), but "NameD" just sits there until I tell it via an
    >> "ndc reload".  The syslog initially reports something like
    >> "name server started ...  but no interfaces."  OK, no problem,
    >> but why does it then take a reload for it to go and look again?

Telling named to reload means it re-reads its config files, reload any
zone files, refresh any slave zones and scan for network interfaces
that have come up or gone down since the last time it scanned them.
Think of it as a global reset and reconfiguration of the name server.
So if you do that after the network interfaces have come alive....

    >> Should I force NameD to listen on [0.0.0.0].53 (i.e. wildcard
    >> the IP address) instead of the default of a socket on each
    >> interface's IP address, at least when starting it?  ...

I don't think that'll work. If there are no interfaces up when named
does an ioctl(.. SIOCGIFCONF ..), then there's nothing available to
set up a port 53 listener apart from the loopback interface. In
networking terms, that's not very interesting because only things on
the local system can use that interface. In fact I think [0.0.0.0]
will be treated by named as a synonym for the loopback interface -
"this host". I've not bothered to check this, so I could be wrong.

    >> Or just forget about it and either change the order so the interfaces
    >> are before the daemons or have a nameserver reload in my system
    >> initialization scripts (to re-read the kernel interface list)?

Well I'd just forget about it. Who cares what PID a process gets and
why should it matter? It also seems very strange to want to start
network services like gated and named before any network interfaces
are switched on.

BTW, the interface-interval clause in BIND8's options{} statement
allows you to tell named how often it should scan for network
interfaces. The default for this interval is 1 hour which is "good
enough" for most people. You could configure named to scan more
frequently, though I don't see the point of this unless network
interfaces get enabled and disabled very frequently on your
system. [Even with a dialup link, the system's network interfaces
should not be changing *that* often.] IIRC gated checks the status of
network interfaces much more often because that is a reasonable thing
for a routing daemon to do. If an interface suddenly comes up, the
routing table probably needs to change and a bunch of RIP or OSPF
updates have to be sent. For a name server, the state of any network
interfaces should hopefully be fairly stable.