community.aegirproject.org

DNS

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Debian/Ubuntu

There is preliminary support for DNS in Aegir's backend that allows it to manage zonefiles dynamically when sites are created. There are still a few major bits missing (described in this meta-ticket) so we generally recommend people use the wildcard approach for now.

That said, while perhaps not yet ready for production use, Aegir's DNS functionality can be quite useful for local development environments. If you run Aegir locally, you're probably in the habit of hacking /etc/hosts regularly, or if you're more adventurous, you've set up a local DNS forwarder, such as dnsmasq. With Aegir's DNS feature, you can avoid this hassle, and let Aegir handle it transparently.

While Aegir supports both BIND and dnsmasq, this documentation will focus on the former. The first step is to install BIND. On Debian-based distros, this will look like:

apt-get install bind9

Next we need to allow the aegir user to run rndc (the name server control utility). On recent Debian systems, this will involve editing /etc/sudoers.d/aegir, whereas on older releases this would be /etc/sudoers. Modify the aegir line to read:

aegir ALL=NOPASSWD: /usr/sbin/apache2ctl, /usr/sbin/rndc

Then we need to make sure the bind user has access to read Aegir's files, so we'll add bind to the aegir group:

adduser bind aegir

We're now ready to activate the feature in Aegir's frontend. Go to Hosting >> Features (admin/hosting/features) and select "DNS Support" under the "Experimental" fieldset, and save the configuration.

Finally, we need to activate DNS on the Aegir server. Visit the server node (hosting/c/server_master) and click the edit tab (which should bring you to node/2/edit). Then under "DNS Service", select "Bind" and then save.

This should trigger a verify of the server (and then probably the platforms on it too), after which Aegir will be managing your local BIND server, and it's zonefile(s). If you have installed Aegir in /var/aegir, put this line in the file /etc/bind/named.conf.local:

include "/var/aegir/config/bind.conf";

Aegir is now a full-fledged DNS server that you can use to resolve addresses locally. This can be accomplished on Debian-like systems by editing /etc/resolv.conf to include "nameserver 127.0.0.1". If you're running Aegir in a VM, you can just point this to the address of the virtual machine.

CentOS/RHEL

You need to have a working DNS/bind/named server for AEgir to take control of. What follows is rough documentation to reach that stage. It is currently UNTESTED in a production environment.

yum -y install bind-chroot bind-utils bind-libs bind
chkconfig named on
ln -s /var/named/chroot/var/named/named.conf /etc/named.conf
cat >> /etc/named.conf << EOF
controls {
        inet 127.0.0.1 allow {
        localnets;
} keys {
        rndckey;
};
};
options {
        listen-on port 53 { any; };
        listen-on-v6 port 53 { ::1; };
        directory       "/var/named";
        dump-file       "/var/named/data/cache_dump.db";
        statistics-file "/var/named/data/named_stats.txt";
        memstatistics-file "/var/named/data/named_mem_stats.txt";

        // Those options should be used carefully because they disable port
        // randomization
        // query-source    port 53;
        // query-source-v6 port 53;
        forwarders { 192.168.122.1; };
        forward only;
//      allow-query     { localhost; };
//      allow-query-cache { localhost; };
};

logging {
        channel default_debug {
                file "data/named.run";
                severity dynamic;
        };
};

view localhost_resolver {
        match-clients      { any; };
        match-destinations { any; };
        recursion yes;
        include "/etc/named.rfc1912.zones";

    // Add local zone definitions here.

    include "/var/aegir/config/bind.conf";
};

include "/etc/rndc.key";
EOF
service named start

Additional Notes

Additional documentation can be found in the Provision DNS module: http://drupalcode.org/project/provision.git/blob/HEAD:/dns/NOTES.