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Topic: dnsmasq returns loopback address upon DNS query

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Post #1
strake
26 Jun 2009, 14:13

I have recently upgraded the firmware on my Linksys WRT54GS to 8.09. I reconfigured dnsmasq to act as my network's DNS server, and edited /etc/hosts accordingly. However, a DNS query from my main PC for "Odin" (this being the name of the WRT itself) returns the IPv6 loopback address as well as the locally-routable addresses:

strake@Loki pts/1 ~ $ host odin
odin.mfd.net has address 192.168.1.1
odin.mfd.net has IPv6 address fdf0:6847:ca1:1:213:10ff:fe10:ab6b
odin.mfd.net has IPv6 address ::1
strake@Loki pts/1 ~ $

This puzzles me, for no IPv4 loopback address is returned. /etc/hosts follows:

### begin /etc/hosts
127.0.0.1     Odin localhost
192.168.1.1   Odin localhost
192.168.1.33  Thor
192.168.1.129 Loki
192.168.1.130 Baldr
192.168.1.5   crossroads

::1                                Odin localhost
FDF0:6847:CA1:1:213:10FF:FE10:AB6B Odin localhost
FDF0:6847:CA1:1:216:17FF:FE1B:A473 Loki
FDF0:6847:CA1:1:2E0:81FF:FE56:AAE8 Thor
### end /etc/hosts

Relevant portion of /etc/config/dhcp follows:

### begin /etc/config/dhcp
config dnsmasq
        option domainneeded     1
        option boguspriv        1
        option filterwin2k      '0'  #enable for dial on demand
        option localise_queries 1
        option local    '/mfd.net/'
        option domain   'mfd.net'
        option expandhosts      1
        option nonegcache       0
        option authoritative    1
        option readethers       1
        option leasefile        '/tmp/dhcp.leases'
        option resolvfile       '/tmp/resolv.conf.auto'
### end /etc/config/dhcp

Why does dnsmasq do this, and how can I prevent it?

Post #2
ecc
23 Jan 2011, 17:37

I don't know why the IPv6 behavior is different from the IPv4 behavior.  But if you change this:

127.0.0.1     Odin localhost
192.168.1.1   Odin localhost
...
::1                                Odin localhost
FDF0:6847:CA1:1:213:10FF:FE10:AB6B Odin localhost

to this:

127.0.0.1     localhost
192.168.1.1   Odin
...
::1                                ipv6-localhost
FDF0:6847:CA1:1:213:10FF:FE10:AB6B Odin

I think you'll get the behavior you want.

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