modify a record entry in Ubuntu bind/dns server

In the /etc/bind directory there is a config file  (most probably named.conf ), that file tells you where the zone files are stored.

grep -i directory /etc/bind/named.conf    #will show:  (f.e.)  then the zone files are in files relative to the directory:
directory "/var/bind";

With each zone:
there is a file systement:

grep -i file /etc/bind/named.conf  # will show where files are  f.e:
file "pri/db.61.168.192.in-addr.arpa";

in this case the zone file for zone  that resolve reverse lookups for 192.168.61.x network:
the file will be in /var/bind/pri/db.61.168.192.in-addr.arpa

When updating the zone file also add one to the serial number in the SOA record

after updating don't forget to restart your name server.

hi noci,

i tried checking name/host/db files but nowhere i found entry or database.

but nslookup and dig still showing the record.

Ah... You're likely having problems with the ridiculously broken systemd-resolved code.

This code is a built in resolver managed by systemd. It has never worked + likely will never work + will put you in a straight jacket in no time, trying to debug it's nonsense.

Hint: You'll never get this code working + you'll never be able to fix any DNS issues while it's running.

First off, before I go into the gory details of how to nuke it completely, see if it's running by posting output of...

systemctl status systemd-resolved | grep loaded
ps fauxww | grep resolved | grep -v grep
netstat -pluten | grep systemd-resolv

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Actually I just found my nuke 'em notes in a server/container setup script I use, so here's how to nuke the code where resolved is dead + will never arise from the dead, as a side effect of a package update (which is frequent).

systemctl stop systemd-resolved
systemctl --now disable systemd-resolved
systemctl mask systemd-resolved
apt-get purge libnss-systemd libnss3
systemctl status systemd-resolved | grep loaded

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There are also some other actions you may take, such as replacing bind with dnsmasq, if you're only running a caching server... so...

Guideline: Only run bind/named is your answering zone record resolution requests, other wise run dnsmasq.

bind can also include files.. so it may be a bit more complex then i assumed...  and the named.conf might have another name of bein another directory. (ps axl | grep named )  should show if there is a different config file.

Also check nsswitch.conf of there is a possibility ldap  (or other lookups) has been configured for host / network lookup).

about systemd.. well not sure why everyone jumped on that band wagon... SYS-V  wasn't nice, but there were/ are better solutions than raping the init system like systemd does.   (openrc does a better jobs of this, even from before systemd).

systemd == abomination