Why hostname -f does not return FQDN

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Hello,

I have my FQDN properly set, but hostname -f (or hostname --fqdn) returns only the short version. Why?

[root@otest ~]# grep HOSTNAME /etc/sysconfig/network
HOSTNAME=otest.lan
[root@otest ~]# hostname
otest.lan
[root@otest ~]# hostname -s
otest
[root@otest ~]# hostname -f
otest