> I believe the 192.168.122.1 comes first due to the
/etc/dhcp/dhclient.conf configuration
Doh — yes, of course. I overlooked the following bit.
>> Put a line into /etc/dhcp/dhclient.conf like so:
>> prepend domain-name-servers 192.168.122.1;
>> Disable the system dnsmasq to prevent it from looping with libvirt's dnsmasq
>> by modifying
>> /etc/NetworkManager/NetworkManager.conf to comment out the following line:
>> #dns=dnsmasq
Note that in connection with my comment #12 you should remove the
"prepend domain-name-servers 192.168.122.1;" from dhclient.conf. The
"resolvconf -a" command takes its place.
If things are set up properly then it won't be necessary to comment out
"dns=dnsmasq" in NetworkManager.conf. Everything should work either with
dns=dnsmasq or without dns=dnsmasq.
For clarity I will describe both cases in detail.
Note that in what follows I have replaced the string "dnsmasq" (which I
used in comment #12) with "dnsmasq-libvirt", this in order to avoid
conflicting with the dnsmasq package; this with an eye to inclusion of
this feature in libvirt and, in so doing, avoiding conflict with the
dnsmasq package. :) Because of this change you will also have to add a
line to /etc/resolvconf/interface-order: just above "lo.dnsmasq" add a
line "lo.dnsmasq-libvirt". Also you will have to do
echo "nameserver 127.0.3.1" | resolvconf -a lo.dnsmasq-libvirt
and
resolvconf -d lo.dnsmasq-libvirt
Why have I used the address 127.0.3.1 here? Because dnsmasq listens at
127.0.0.1; dnsmasq-NM listens at 127.0.1.1; and dnscrypt-proxy listens
at 127.0.2.1.
Also you will have to create a directory /var/run/dnsmasq-libvirt/ and
modify the hook script to write /var/run/dnsmasq-libvirt/resolv.conf
instead of /var/run/dnsmasq/resolv.conf.
OK. Assume that your ISP has a nameserver NI which resolves Internet
names. Assume your router's nameserver NR resolves your LAN names and
forwards queries for other names to NI. Assume machines on your LAN have
a resolv.conf containing "nameserver addrR" where addrR is the address
of the router.
1. Consider the case where you have "dns=dnsmasq" in NetworkManager.conf
on your laptop which runs NetworkManager (NM). Assume NM gets the
laptop's IP address and nameserver address addrR via DHCP from the DHCP
server running on the router. NM starts a local dnsmasq instance
(dnsmasq-NM) and passes addrR to dnsmasq-NM. dnsmasq-NM then listens
locally at 127.0.1.1 and forwards all queries to addrR. NM adds a record
called "NetworkManager" to resolvconf's database containing "nameserver
127.0.1.1".
Now you start libvirt. Libvirt starts a dnsmasq instance, dnsmasq-
libvirt, and adds a record called "lo.dnsmasq-libvirt" to resolvconf's
database by means of the command 'echo "nameserver 127.0.3.1" |
resolvconf -a lo.dnsmasq-libvirt'. When the database is updated the
resolvconf update hook scripts are run. dnsmasq-libvirt has such a hook
script which reads in the database records in the order determined by
/etc/resolvconf/interface-order, excludes the one called 'lo.dnsmasq-
libvirt' and generates /var/run/dnsmasq-libvirt/resolv.conf containing
"nameserver 127.0.1.1". When the latter file changes, the dnsmasq-
libvirt process notices this and reads the file and is thereby
configured to forward queries that it can't itself answer to 127.0.1.1.
Another resolvconf update hook script called 'libc' generates a new
resolv.conf file containing "nameserver 127.0.3.1". Resolver clients on
the laptop thus query dnsmasq-libvirt which queries dnsmasq-NM which
queries NR which queries NI.
2. Consider now the case where you have "#dns=dnsmasq". NM gets the
laptop's IP address and addrR via DHCP. NM adds a record called
"NetworkManager" to resolvconf's database containing "nameserver addrR".
Now you start libvirt. Libvirt starts dnsmasq-libvirt and adds a record
called "lo.dnsmasq-libvirt" to resolvconf's database. When the database
is updated, dnsmasq-libvirt's resolvconf-update hook script is run and
generates /var/run/dnsmasq-libvirt/resolv.conf containing "nameserver
addrR". dnsmasq-libvirt is thus configured to forward queries to addrR.
The libc hook script generates resolv.conf containing "nameserver
127.0.3.1". Resolver clients on the laptop thus query dnsmasq-libvirt
which queries NR which queries NI.
3. Consider now case #1 where you add dnsmasq-server (from the "dnsmasq"
package) into the mix. Dnsmasq-server forwards to dnsmasq-NM — this
already works. Dnsmasq-libvirt should forward to dnsmasq-server. If you
have set things up as decribed above then this should happen.
> I've made some changes to my /etc/init/lxc-net script, stolen the dnsmasq
> package's
> resolvconf hook script -- I'll test it shortly. Thanks!
Cool! Once this is working it should be considered for incorporation
into libvirt.
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https://bugs.launchpad.net/bugs/1163147
Title:
Please run dnsmasq in such a way that it can also be used on the host
— to look up the VMs' names
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