kinit error

[sam]

Hi,

does anyone know why I get the following error:
root at fbsd [10:56am] [~]# kinit tillman
tillman at ROCK.COM's Password:
kinit: krb5_get_init_creds: unable to reach any KDC in realm ROCK.COM
root at fbsd [10:57am] [~]#

I have written the following kerberos lines in a seperate DNS server:

kerberos                CNAME 192.168.1.1

_kerberos               IN TXT  ROCK.COM
_kerberos._udp          IN SRV  0 0 88 kerberos.rock.com
_kerberos-master._udp   IN SRV  0 0 88 kerberos.rock.com
_kerberos-adm._tcp      IN SRV  0 0 749 kerberos.rock.com
_kpasswd._udp           IN SRV  0 0 464 kerberos.rock.com

but pinging from another machine to kerberos server is failed, I m not 
sure if this is the problem. What is the correct way to setup DNS to 
include kerberos configuratoin?

Thanks
sam