Determine FQDN when hostname doesn't give it?
It appears that under-the-hood, Puppet uses Facter to evaluate the domain names:
$ facter domain
domain.com
$ facter hostname
kungfumaster
$ facter fqdn
kungfumaster.domain.com
The answer is in the relevant Facter source code.
It does the following in order and uses the first one that appears to contain a domain name:
- hostname -f
- dnsdomainname
- parsing resolv.conf for a "domain" or "search" entry
Probably because your system is part of a domain network that assigns a domain name. For example in my case, my router resolves all hostnames in the form of host.lan, "lan" being my domain, and "host" the name of my system.
The FQDN most likely comes from your router DNS, just run whatever you like of these commands:
nslookup your-ip-here
dig -x your-ip-here
host your-ip-here
An example using dig:
dig @10.0.0.1 -x 10.0.0.1
; <<>> DiG 9.9.5-4-Debian <<>> @10.0.0.1 -x 10.0.0.1
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 11384
;; flags: qr aa rd ad; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;1.0.0.10.in-addr.arpa. IN PTR
;; ADDITIONAL SECTION:
1.0.0.10.in-addr.arpa. 86400 IN PTR dsldevice.lan.
;; Query time: 2181 msec
;; SERVER: 10.0.0.1#53(10.0.0.1)
;; WHEN: Thu Jun 19 20:01:32 AST 2014
;; MSG SIZE rcvd: 77
Since I use my own DNS and not the router's I have to set the domain to query in the @ part. I'm querying the routers' own domain name.
You will find that it will return the domain name as your DNS/router sees you. There are various ways to disable this in the router, but I've found that the most easier way is just using other DNS.