Migrating to PowerDNS
Before migrating to PowerDNS a few things should be considered.
PowerDNS does not operate as a 'slave' or 'master' server with all backends. The Generic SQL, BIND backends have the ability to act as master or slave. See the table of backends which other backends support these modes.
Using AXFR to a Slave-Capable Backend
The easiest way to migrate all your zones from your old infrastructure to PowerDNS
is to add all your domains as a slave domain with your current master as the
master, wait for the zones to be transferred and change the zones to master.
Make sure slave
is set to "yes" in your pdns.conf.
To A Generic SQL Backend
Note: This assumes the schema provided with PowerDNS is in place
In order to migrate to a Generic SQL backend, add all your domains to the 'domains' table with the IP of your current master. On your current master, make sure that this master allows AXFRs to this new slave.
INSERT INTO domains (name,type,master) VALUES ('example.net', 'SLAVE', '198.51.100.101');
Then start PowerDNS and wait for all the zones to be transferred. If this server is the new master, change the type of domain in the database:
UPDATE domains set type='MASTER' where type='SLAVE';
And set master
to "yes" in your pdns.conf and restart
PowerDNS.
Or, if you want to use native:
UPDATE domains set type='NATIVE' where type='SLAVE';
To the BIND backend
Create a named.conf with all the domains as slave domains, e.g.:
zone "example.net" in {
type slave;
file "/var/lib/powerdns/zones/example.net.zone";
masters {
198.51.100.101;
};
};
Make sure the directory is writable for the pdns_server
process and that bind-config
parameter references this file. Now start PowerDNS and wait untill all zones are
transferred. Now you can change the zone type to master:
zone "example.net" in {
type master;
file "/var/lib/powerdns/zones/example.net.zone";
};
Don't forget to enable master
in your pdns.conf and restart,
or if this setting was already set, use pdns_control rediscover
to load these
zones as master zones.
From zonefiles to PowerDNS
Using the BIND backend
To use the bind backend, set launch=bind
and bind-config=/path/to/named.conf
in your pdns.conf
. Note that PowerDNS will not honor any options from named.conf,
it will only use the zone
statements. See the Bind backend
documentation for more information.
To a Generic SQL backend
There are several methods to migrate to a Generic SQL backend.
Using zone2sql
To migrate, the zone2sql
tool is provided. This tool parses a BIND named.conf
file and zone files and outputs SQL on standard out, which can then be fed to your
database. It understands the Bind master file extension $GENERATE
and will also
honour $ORIGIN
and $TTL
.
For backends supporting slave operation, there is also an option to keep slave zones as slaves, and not convert them to native operation.
zone2sql
can generate SQL for nearly all the Generic SQL backends. See its
manpage for more information.
An example call to zone2sql
could be:
zone2sql --named-conf=/path/to/named.conf --gmysql | mysql -u pdns -p pdns-db
This will generate the SQL statements for the Generic MySQL and pipe them into the pdns-db database in MySQL.
Using pdnsutil load-zone
The pdnsutil
tool has a load-zone
command that ingests a zone file and imports it into the first backend that is capable of hosting it.
To import, configure the backend and run pdnsutil load-zone example.com /tmp/example.com.com.zone
to import the example.com
domain from the /tmp/example.com.zone
file.
The zone is imported atomically (i.e. it is fully imported, or not) and any existing records for that zone are overwritten.
Migrating Data from one Backend to Another Backend
NB! This is experimental feature.
Syntax: pdnsutil b2b-migrate old new
This tool lets you migrate data from one backend to another, it moves all data, including zones, metadata and crypto keys (if present). Some example use cases are moving from Bind style zonefiles to SQL based, or other way around, or moving from MyDNS to gMySQL.
Prerequisites
- Target backend must support same features as source from set of domains, zones, metadata, DNSSEC and TSIG. See Backend Capabilities
- There must be no data in the target backend, otherwise the migration will fail. This is checked.
You can perform live upgrade with this tool, provided you follow the procedure.
Moving from source to target.
- Take backups of everything.
- Configure both backends to pdns.conf, if you have source configured, you can just add target backend. DO NOT RESTART AUTH SERVER BEFORE YOU HAVE FINISHED
- Then run
pdnsutil b2b-migrate old new
, the old and new being configuration prefixes in pdns.conf. If something goes wrong, make sure you properly clear ALL data from target backend before retrying. - Remove (or comment out) old backend from pdns.conf, and run
pdnsutil rectify-all-zones
andpdnsutil check-all-zones
to make sure everything is OK. - If everything is OK, then go ahead to restart your PowerDNS service. Check logs to make sure everything went ok.