Simon Kelley on 18/03/09 11:33, wrote:
Adam Hardy wrote:
after running smoothly for months, my network went snafu today and in
the process of putting it back to normal, I found errors logged into
/var/log/messages from dhclient on my main workstation.
I didn't get this issue before IIRC
It makes me wonder if I have installed something from debian which is
causing the problem ('Unable to add forward map...')
I get precious little from my google and mailing list searches. Is
this a problem due to packages like mDNS or Avahi-daemon [1] - or
could it be my iptables rules which have thrown a spanner in the
works? (which I also changed since my dnsmasq install).
Mar 17 16:32:37 localhost dhclient: DHCPREQUEST on eth0 to 192.168.0.2
port 67
Mar 17 16:32:37 localhost dhclient: DHCPACK from 192.168.0.2
Mar 17 16:32:37 localhost dhclient: bound to 192.168.0.235 -- renewal
in 1631 seconds.
Mar 17 16:32:38 localhost dhclient: Unable to add forward map from
gondor.localdomain. to 192.168.0.235: destination address required
Mar 17 16:59:48 localhost dhclient: DHCPREQUEST on eth0 to 192.168.0.2
port 67
Mar 17 16:59:48 localhost dhclient: DHCPACK from 192.168.0.2
Mar 17 16:59:48 localhost dhclient: bound to 192.168.0.235 -- renewal
in 1226 seconds.
Mar 17 16:59:49 localhost dhclient: Unable to add forward map from
gondor.localdomain. to 192.168.0.235: destination address required
[1] suspicious:
Mar 17 16:05:33 localhost avahi-daemon[2292]: New relevant interface
eth0.IPv4 for mDNS.
Mar 17 16:05:33 localhost avahi-daemon[2292]: Joining mDNS multicast
group on interface eth0.IPv4 with address 192.168.0.235.Mar 17
16:05:33 localhost avahi-daemon[2292]: Registering new address record
for 192.168.0.235 on eth0.
M
It looks like dhclient is trying to update it's DNS records in a DNS
server using the dynamic-dns protocol. I doubt that this is anything to
do with avahi. More likely a change in dhclient configuration.
Do you have something like "do-forward-updates true;" in dhclient.conf?
If you are using dnsmasq, you don't need to use DDNS updates: the
dnsmasq DNS server doesn't support them, but it doesn't need them
because DNS records are inserted automatically from DHCP addresses.
Hi Simon,
thanks for the reply. So you're saying it's harmless then? I have this paranoia
that my broadband speed is being cut by the way I've configured my network, due
to BT giving me so much FUD.
Anyway my main aim is to make sure it's all working fine before I upgrade Debian
from Etch to Lenny.
I wasn't aware that I had configured anything to do DDNS updates. This is all I
have in dhclient.conf:
send dhcp-lease-time 3600;
request subnet-mask, broadcast-address, time-offset, routers,
domain-name, domain-name-servers, host-name,
netbios-name-servers, netbios-scope, interface-mtu;
send fqdn.fqdn "gondor.localdomain.";
send fqdn.encoded on;
send fqdn.server-update off;
Perhaps it is on by default and I need to turn it off? There are also a couple
of scripts in the dhclient-enter-hooks.d for samba, ntpdate, ntp and debug,
although from their content, they don't look relevant.
Most of the stuff out there I see when searching on "DDNS dhclient update" is
for freeBSD with little for Linux.
As an appendix, here's my dhcpd.conf from the server (is this redundant with
dnsmasq?) running dnsmasq:
ddns-update-style none;
option domain-name "domain01";
option domain-name-servers 194.74.65.69, 217.35.209.180;
default-lease-time 600;
max-lease-time 7200;
authoritative;
log-facility local7;
subnet 192.168.0.0 netmask 255.255.255.0 {
range 192.168.0.3 192.168.0.254;
option subnet-mask 255.255.255.0;
option broadcast-address 192.168.0.255;
option routers 192.168.0.2;
}
and the dnsmasq.conf:
domain-needed
bogus-priv
filterwin2k
local=/localdomain/
domain=localdomain
dhcp-range=192.168.0.3,192.168.0.254
dhcp-option=26,1500
log-queries
