DNS TTL on INN

[Elia]

Good evening,

I have recently changed the IP address of my news server, also updated
the DNS entry. Issue is, the sites I peer with seem to update the IP
address associated to the hostname, meaning that my server cannot
recieve feeds from them, nor are they pulling feeds from mine.

Does anyone have experience with that issue? Don't want to wait a few
days just to find out they have to restart INN or something in that way.

Kind Regards,
Elia

[Richard Kettlewell]

Depends on the server, but with INN, the peer must use ctlinnd to reload
incoming.conf. Many servers do this automatically once a day. Because of
this it’s worth a note to peers when you renumber (and also worth
keeping renumbering very rare!)

In my logs, there’s an outage for your server overnight between
approximately 2330 and 0302 UTC (when my daily reload happens), after
which connectivity returns to normal.

--
https://www.greenend.org.uk/rjk/

[Julien ÉLIE]

Hi all,

>> Does anyone have experience with that issue? Don't want to wait a few
>> days just to find out they have to restart INN or something in that way.
>

> I didn't check the "current" code (still running inn < 2.3 with real
> tradspool (i.e no changed overview file naming scheeme)), but in the past
> inn did the name/ip resolution _only_ at startup (it's not a bug, it's a
> feature)

This is unfortunately still a feature, indeed :)

The expected move is to use libevent in INN to handle asynchronous DNS
lookups, but that's a bit of work still not tackled:
https://github.com/InterNetNews/inn/issues/89

(Implementing libevent in innd and innfeed would then also ease a native
support of TLS and COMPRESS between peers.)


In addition to Richard's message about reloading incoming.conf, yes,
that's the current way to handle the issue. Some distributions (like at
least Debian) come with an already configured crontab to do that.
I suggest, Elia, if you don't already have the reload in crontab, to
have a look at the "Setting Up the Cron Jobs" section of INSTALL:
https://www.eyrie.org/~eagle/software/inn/docs/install.html#S12

--
Julien ÉLIE

« If you lie to the compiler, it will get its revenge. » (Henry Spencer)

[Adam W.]

Elia <m...@elia.li> wrote:

> I have recently changed the IP address of my news server, also updated
> the DNS entry. Issue is, the sites I peer with seem to update the IP
> address associated to the hostname, meaning that my server cannot
> recieve feeds from them, nor are they pulling feeds from mine.

I remember when I did it. I moved the server to another machine, so
obviously the IP has changed. I made a transition period, where I added
iptables rules to the old server to direct traffic over VPN to the new
server (each peer had its own private IP assigned in this VPN, and it was
used as a source IP).

Outgoing traffic was handled similarly -- routed through the old server.

Then I notified peers about the IP change and waited patiently. Once they
confirmed the change and I confirmed that they connect to the proper IP, I
redirected outgoing traffic, so it originated from the proper IP, and
removed the incoming traffic rule.

The same was true for readers. During the transition period they were able
to connect to and use both IPs.

It was a little pain to set up, but made the transition smooth and there
was almost no disruption (minus the time needed to shut down the server,
copy everything, and restart it at the new location).

But... there's one server that's almost abandoned, that made the
transition automatically. I don't know if it reloads incoming.conf daily,
or what, but the IP has changed, and the server switched to the new one
(probably overnight) and I'm almost sure there was no admin intervention.

[Elia]

Yup, that seems to be when i changed IP's. Just waited a day and now
everything is in order again.

Funny thing is, in the middle of the night I changed the IP's back
again, and seemingly exactly when my peers reloaded. So I had the wrong
IP twice. Learned my lesson now, gonna notify before i (hopefully not in
the near future) need to change ip's.