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Hi,<br>
<br>
<br>
the ISC DHCP documentation says that which the interim DNS update
scheme, the DHCP server uses the hostname from the fqdn or hostname
option that the client sends. The domain part is being taken from
the ddns-domainname config option as per manpage.<br>
<br>
This seems to be reflected in the standard definitions in
server/dhcpd.c:<br>
<br>
option server.ddns-hostname
= \n\<br>
pick (option fqdn.hostname, option
host-name); \n\<br>
option server.ddns-domainname = config-option
domain-name; \n\<br>
option server.ddns-rev-domainname = \"in-addr.arpa.\";";<br>
<br>
There also is a "ddns-hostname" config option which I expected to
override the client's request data. So I use host definitions like
this:<br>
<br>
<font face="Arial">host ddns-0000017 {<br>
option host-name "labprinter1";<br>
hardware ethernet 00:22:33:44:55:66;<br>
option domain-name "unknown";<br>
ddns-updates on;<br>
do-forward-updates on;<br>
do-reverse-updates on;<br>
ddns-hostname "labprinter1";<br>
ddns-domainname "unknown";<br>
}</font><br>
<br>
However, I have found that at least the reverse entry (PTR record)
was "test.test" in my case, when I coerced the client to send a FQDN
option (81) with that value.<br>
<br>
Is there a way that I can use only the host- and domain-names (e.g.
"labprinter1.unknown" in my example above) from my host entry for
both forward and reverse DDNS updates no matter what the client
thinks what its name he has? I do not want my DHCP servers to act as
a stand-in for a DNS modification attack.<br>
<br>
<br>
Thanks for any hints...<br>
<br>
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