[Freeipa-users] Using fqdn in /etc/hostname causes duplicate domain in DHCP dyndns update

[Kees Bakker]

Hey,

Hopefully someone here can hint me towards a (easier) solution.

In short, for correct DHCP-DDNS updates there should be a non-fqdn in /etc/hostname
To install IPA client I am forced to have a fqdn in /etc/hostname. But now the DHCP-DDNS
results in duplicated domain portion of the DNS entries.

The details.
We have a FreeIPA environment with DNS and DHCP. I've configured bind and
dhcpd to do DDNS. For the most part it is working as expected.

When the hostname of a system is a non-fqdn the end result is what I want to see. Say I have
    /etc/hostname: test02
then after it started up there is a new forward map (using "mydomain" here instead of the real thing).
   test01 -> 172.16.16.252
and a reverse map in 16.16.172.in-addr.arpa zone
   252 -> test02.mydomain

Some lines from /var/log/syslog
dhcpd[82333]: DHCPOFFER on 172.16.16.252 to 00:16:3e:8e:91:12 (test02) via eno1
named-pkcs11[82428]: client 172.16.16.75#23238/key dhcp_updater: updating zone 'mydomain/IN': adding an RR at 'test02.mydomain' A 172.16.16.252
dhcpd[82333]: DHCPREQUEST for 172.16.16.252 (172.16.16.75) from 00:16:3e:8e:91:12 (test02) via eno1
dhcpd[82333]: DHCPACK on 172.16.16.252 to 00:16:3e:8e:91:12 (test02) via eno1
named-pkcs11[82428]: client 172.16.16.75#23238/key dhcp_updater: updating zone 'mydomain/IN': adding an RR at 'test02.mydomain' DHCID AAAB6QGH0W+JCSMwrj9sQVCeh5PToZAmWZvMpgiEtXHrZgE=
dhcpd[82333]: Added new forward map from test02.mydomain to 172.16.16.252
named-pkcs11[82428]: client 172.16.16.75#23238/key dhcp_updater: updating zone '16.16.172.in-addr.arpa/IN': adding an RR at '252.16.16.172.in-addr.arpa' PTR test02.mydomain.
dhcpd[82333]: Added reverse map from 252.16.16.172.in-addr.arpa. to test02.mydomain

However, when I want to add this system as a IPA client I am forced to
fill in a fqdn in /etc/hostname. So I change /etc/hostname to have test01.mydomain
The provisioning succeeds and all seems well.

But after a reboot the system requests DHCP to register as test01.mydomain. And
the DHCP server does a DNS update for test01.mydomain.mydomain.
The DNS zone for mydomain now has
    test01 for all the SSHFP records
    test01.mydomain for the A record
The reverse map for 16.16.172.in-addr.arpa has
    231 -> test01.mydomain.mydomain

named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone 'mydomain/IN': deleting an RR at test02.mydomain A
dhcpd[4550]: DHCPREQUEST for 172.16.16.252 from 00:16:3e:8e:91:12 (test02) via eno1
dhcpd[4550]: DHCPACK on 172.16.16.252 to 00:16:3e:8e:91:12 (test02.mydomain) via eno1
dhcpd[4550]: Removed forward map from test02.mydomain to 172.16.16.252
named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone 'mydomain/IN': deleting an RR at test02.mydomain DHCID
named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone 'mydomain/IN': adding an RR at 'test02.mydomain.mydomain' A 172.16.16.252
named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone 'mydomain/IN': adding an RR at 'test02.mydomain.mydomain' DHCID AAAB+5EmVxuf4utDMDZxjqAiqIds6Briv5awEp5W3whNsLc=
dhcpd[4550]: Added new forward map from test02.mydomain.mydomain to 172.16.16.252
named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone '16.16.172.in-addr.arpa/IN': adding an RR at '252.16.16.172.in-addr.arpa' PTR test02.mydomain.mydomain.
dhcpd[4550]: Added reverse map from 252.16.16.172.in-addr.arpa. to test02.mydomain.mydomain


To work around I then change the /etc/hostname back to test01, restart
the network and everything if fine afterwards.

named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone 'mydomain/IN': deleting an RR at test02.mydomain.mydomain A
dhcpd[4550]: DHCPRELEASE of 172.16.16.252 from 00:16:3e:8e:91:12 (test02.mydomain) via eno1 (found)
dhcpd[4550]: Removed forward map from test02.mydomain.mydomain to 172.16.16.252
named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone 'mydomain/IN': deleting an RR at test02.mydomain.mydomain DHCID
dhcpd[4550]: DHCPOFFER on 172.16.16.252 to 00:16:3e:8e:91:12 (test02) via eno1
named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone 'mydomain/IN': update unsuccessful: test02.mydomain: 'name not in use' prerequisite not satisfied (YXDOMAIN)
dhcpd[4550]: DHCPREQUEST for 172.16.16.252 (172.16.16.75) from 00:16:3e:8e:91:12 (test02) via eno1
dhcpd[4550]: DHCPACK on 172.16.16.252 to 00:16:3e:8e:91:12 (test02) via eno1
named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone 'mydomain/IN': deleting rrset at 'test02.mydomain' DHCID
named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone 'mydomain/IN': adding an RR at 'test02.mydomain' DHCID AAAB6QGH0W+JCSMwrj9sQVCeh5PToZAmWZvMpgiEtXHrZgE=
named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone 'mydomain/IN': deleting rrset at 'test02.mydomain' A
named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone 'mydomain/IN': adding an RR at 'test02.mydomain' A 172.16.16.252
dhcpd[4550]: Added new forward map from test02.mydomain to 172.16.16.252
named-pkcs11[82428]: client 172.16.16.75#61759/key dhcp_updater: updating zone '16.16.172.in-addr.arpa/IN': adding an RR at '252.16.16.172.in-addr.arpa' PTR test02.mydomain.
dhcpd[4550]: Added reverse map from 252.16.16.172.in-addr.arpa. to test02.mydomain
-- 
Kees