dhcpd bashing head on dns wall

rbees · 05-11-2014, 07:56 PM

bind9 and dhcpd are not playing nice

Fresh install of Debian Wheezy, no gui. For some reason that I have not found dhcpd will not update the dns records. I have the same key in both /etc/dhcp and /etc/bind. Bind is chrooted.

Code:

From dhcpd.conf
include "/etc/dhcp/ddns.key"; 
   
  
Contents of ddns.key
    key DDNS_UPDATE {                                                                                      
        algorithm HMAC-MD5.SIG-ALG.REG.INT;                                                            
        secret  "somestring";

Code:

From named.conf.local
include "/etc/bind/ddns.key";


Contents of ddns.key
    key DDNS_UPDATE {                                                                                      
        algorithm HMAC-MD5.SIG-ALG.REG.INT;                                                            
        secret  "the same somestring";

webmin was not playing nice with the chroot-bind so I

ln -s /var/bind9/chroot/var/cache/bind /var/cache/bind

When I connect up a new new machine I get

Code:

May 11 17:44:41 external dhcpd: DHCPDISCOVER from 12:34:56:78:90:ab via eth1                            
May 11 17:44:42 external dhcpd: DHCPOFFER on 192.168.7.25 to 12:34:56:78:90:ab (BumbleBee) via eth1     
May 11 17:44:42 external dhcpd: DHCPREQUEST for 192.168.7.25 (192.168.7.1) from 12:34:56:78:90:ab (BumbleBee) via eth1                                                                     
May 11 17:44:42 external dhcpd: DHCPACK on 192.168.7.25 to 12:34:56:78:90:ab (BumbleBee) via eth1       
May 11 17:44:54 external dhcpd: Unable to add forward map from BumbleBee.Torah-disciple.local to 192.168.7.25: timed out

The permissions on my zone files are 644

so I added a line in my /etc/bind/named.conf.options

allow-update { 127.0.0.1; };

no joy

rbees · 05-11-2014, 10:22 PM

I put the configs at http://pastebin.com/Scfxig9c

rbees · 05-12-2014, 07:22 PM

Well i thought I found it twice. NOT

grrr

One was a required sym-link in /var/cache/bind but they are already there.

The other was a missing statement in the dhcpd.conf zone sections key DDNS_UPDATE

neither brought joy

rbees · 05-12-2014, 07:31 PM

Not sure dns is even working. nslookup does not even return the host own name. It hits the plastic box router that is feeding it and not its self or the the OpenDns servers it is suppose to.

/me pounds head on dns wall some more.

rbees · 05-12-2014, 09:38 PM

K got that fixed. Dhclient was set to pull lots of stuff from my isp and was over writing resolv.conf But dhcpd still timing out when trying to update the zone files.

psycroptic · 05-12-2014, 10:45 PM

Quote:

Originally Posted by rbees

K got that fixed. Dhclient was set to pull lots of stuff from my isp and was over writing resolv.conf But dhcpd still timing out when trying to update the zone files.

what do your logs show when dhcpd fails? could potentially be file permissions on the zone files

rbees · 05-13-2014, 05:39 AM

thanks psycroptic

the logs still show nothing except as posted above

unable to add forward map..... timed out

rbees · 05-13-2014, 05:07 PM

/me is now bashing head on nat wall

Grrr

I I got the local name resolution working but now nat is not.

The only thing I changed was in dhclient.conf got rid of all the dns stuff that was rewriting my resolve.conf and then a restart.

rbees · 05-13-2014, 05:18 PM

Something about commenting out the first line and changing the rest seems to have caused the problem.

Code:

#send host-name = gethostname();

request subnet-mask, broadcast-address, time-offset, routers,
        interface-mtu, rfc3442-classless-static-routes, ntp-servers;

#request subnet-mask, broadcast-address, time-offset, routers,
#       domain-name, domain-name-servers, domain-search, host-name,
#       dhcp6.name-servers, dhcp6.domain-search,
#       netbios-name-servers, netbios-scope, interface-mtu,
#       rfc3442-classless-static-routes, ntp-servers;

Code:

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
default         external.Torah- 0.0.0.0         UG    0      0        0 eth1
192.168.0.0     *               255.255.255.0   U     0      0        0 eth0
192.168.7.0     *               255.255.255.224 U     0      0        0 eth1

I can clearly see that the gateway is on the wrong interface. But i don't know how what I need to put back in the dhclient.conf to get it back on eth0 and still have local name resolution.