Hello Knot developers,
Suppose I am running two Knot DNS instances. They're listening on
different interfaces, and slaving different sets of zones. If the
"storage" variable is the same for these two, then the two instances of
knotd will both try to write into storage/journal and storage/timers.
Is this safe to do? My understanding of LMDB is that a database can be
shared between different threads and processes because they using locking.
Regards,
Anand
Hello Knot DNS developers,
I have an observation about newer versions of Knot which use the new
single LMDB-based journal.
Suppose I have 3 slave zones configured in my knot.conf. Let's call them
zone1, zone2 and zone3. Knot loads the zones from the master and writes
data into the journal. Now suppose I remove one zone (zone3) from the
config, and reload knot. The zone is no longer configured, and querying
knot for it returns a REFUSED response. So far all is according to my
expectation.
However, if I run "kjournalprint <path-to-journal> -z", I get:
zone1.
zone2.
zone3.
So the zone is no longer configured, but its data persists in the
journal. If I run "knotc -f zone-purge zone3." I get:
error: [zone3.] (no such zone found)
I'm told that I should have done the purge first, *before* remove the
zone from the configuration. However, I find this problematic for 2 reasons:
1. I have to remember to do this, and I'm not used to this modus
operandi; and
2. this is impossible to do on a slave that is configured automatically
from template files. On our slave servers, where we have around 5000
zones, the zones are configured by templating out a knot.conf. Adding
zones is fine, but if a zone is being deleted, it will just disappear
from knot.conf. We keep no state, and so I don't know which zone is
being removed, and cannot purge it before-hand.
Now, the same is kind of true for Knot < 2.4. But... there is one major
difference. Under older versions of Knot, zone data was written into
individual files, and journals were written into individual .db files. I
can run a job periodically that compares zones in knot.conf with files
on disk, and delete those files that have no matching zones in the
config. This keeps the /var/lib/knot directory clean.
But in newer versions of Knot, there is no way to purge the journal of
zone data once a zone is removed from the configuration. For an operator
like me, this is a problem. I would like "knotc zone-purge" to be able
to operate on zones that are no longer configured, and remove stale data
anyway.
Hi Knot folks,
I just tried to view https://www.knot-dns.cz/ and it gave me an HTTP 404
error. After trying to reload it twice, I got the front page, but the
other parts of the site (documentation, download, etc) are all still
giving me HTTP 404 errors.
Regards,
Anand
Dear Knot DNS and Knot Resolver users,
in order to unite the git namespaces and make it more logical we
have move the repositories of Knot DNS and Knot Resolver under the
knot namespace.
The new repositories are located at:
Knot DNS
https://gitlab.labs.nic.cz/knot/knot-dns
Knot Resolver:
https://gitlab.labs.nic.cz/knot/knot-resolver
The old git:// urls were kept same:
git://gitlabs.labs.nic.cz/knot-dns.git
git://gitlabs.labs.nic.cz/knot-resolver.git
Sorry for any inconvenience it might have caused.
Cheers,
--
Ondřej Surý -- Technical Fellow
--------------------------------------------
CZ.NIC, z.s.p.o. -- Laboratoře CZ.NIC
Milesovska 5, 130 00 Praha 3, Czech Republic
mailto:ondrej.sury@nic.cz https://nic.cz/
--------------------------------------------
Am 09.07.2017 um 12:30 schrieb Christoph Lukas:
> Hello list,
>
> I'm running knot 2.5.2 on FreeBSD.
> In an attempt to resolve a recent semantic error in one of my zonefiles,
> the $storage/$zone.db (/var/db/knot/firc.de.db) file got lost.
> Meaning: I accidentally deleted it without a backup.
> At point of deletion, the .db file was 1.6 MB in size.
> The actual zone file was kept, the journal and DNSSEC keys untouched,
> the zone still functions without any issues.
>
> The zone is configured as such in knot.conf:
> zone:
> - domain: firc.de
> file: "/usr/local/etc/knot/zones/firc.de"
> notify: inwx
> acl: acl_inwx
> dnssec-signing: on
> dnssec-policy: rsa
>
>
> This raises the following questions:
>
> 1) What is actually in those .db files?
> 2) Are these any adverse effects to be expected now that I don't have
> the file / need to re-create it?
> 3) How can I re-create the file?
>
> Any answers will be greatly appreciated.
>
> With kind regards,
> Christoph Lukas
>
As answered in
https://lists.nic.cz/pipermail/knot-dns-users/2017-July/001160.html
those .db files are not required anymore.
I should have read the archive first ;)
With kind regards,
Christoph Lukas
Hi,
I am running Knot 2.5.2-1 on a Debian Jessie, all is good, no worries.
I am very pleased with Knot's simplicity and ease of configuration -
which are still readable as well!
I noticed recently that I am getting
knotd[9957]: notice: [$DOMAIN.] journal, obsolete exists, file '/var/lib/knot/zones/$DOMAIN.db'
everytime I restart Knot. I get these for all my domains I have confgured,
and there is one in particular providing my own .dyn. service :-) - so I
am a bit reluctant - just to delete it.
But all the .db files have a fairly old timestamp (Feb 2017) and about the
same. At that time (Feb 2017) I was running just one authoritative Master
instance, nothing fancy. lsof also doesn't report any open files. At
that time (Feb 2017) I was running just one authoritative Master
instance, nothing else.
Can I just delete those files?
Cheers
Thomas
Hello knot,
I have recently started a long over due migration to knot 2.* and I have noticed that the server.workers config stanza is now split into three separate stanzas [server.tcp-workers, server.udp-workers & server.background-workers]. Although this is great for flexibility it does make automation a little bit more difficult. With the 1.6 configuration I could easily say something like the following
workers = $server_cpu_count - 2
This meant I would always have 2 cpu cores available for other processes e.g. doc, tcpdump. With the new configuration I would need to do something like the following
$avalible_workers = $server_cpu_count - 2
$udp_workers = $avalible_workers * 0.6
$tcp_workers = $avalible_workers * 0.3
$background_workers = $avalible_workers * 0.1
The above code is lacking error detection and rounding corrections which will add further complexity and potentially lacking itelagence that is available in knot to better balance resources. As you have already implemented logic in knot to ensure cpus are correctly balanced I wonder if you could add back a workers configurations to act as the upper bound used in the *-workers configuration. Such that
*-workes defaults:
"Default: auto-estimated optimal value based on the number of online CPUs or the value set by `workers` which ever is lower)
Thanks
John
