Migration

Upgrade 2.4.x to 2.5.x

This chapter describes some steps necessary after upgrading Knot DNS from version 2.4.x to 2.5.x.

Building changes

The --enable-dnstap configure option now enables the dnstap support in kdig only! To build the dnstap query module, --with-module-dnstap have to be used.

Since Knot DNS version 2.5.0 each query module can be configured to be:

  • disabled: --with-module-MODULE_NAME=no
  • embedded: --with-module-MODULE_NAME=yes
  • external: --with-module-MODULE_NAME=shared (excluding dnsproxy and onlinesign)

The --with-timer-mapsize configure option was replaced with the runtime max-timer-db-size configuration option.

KASP DB migration

Knot DNS version 2.4.x and earlier uses JSON files to store DNSSEC keys metadata, one for each zone. 2.5.x versions store those in binary format in a LMDB, all zones together. The migration is possible with the pykeymgr script:

$ pykeymgr -i path/to/keydir

The path to KASP DB directory is configuration-dependent, usually it is the keys subdirectory in the zone storage.

In rare installations, the JSON files might be spread across more directories. In such case, it is necessary to put them together into one directory and migrate at once.

Configuration changes

It is no longer possible to configure KASP DB per zone or in a non-default template. Ensure just one common KASP DB configuration in the default template.

As Knot DNS version 2.5.0 brings dynamically loaded modules, some modules were renamed for technical reasons. So it is necessary to rename all occurrences (module section names and references from zones or templates) of the following module names in the configuration:

mod-online-sign -> mod-onlinesign

mod-synth-record -> mod-synthrecord

Upgrade 2.5.x to 2.6.x

Upgrading from Knot DNS version 2.5.x to 2.6.x is almost seamless.

Configuration changes

The dsa and dsa-nsec3-sha1 algorithm values are no longer supported by the algorithm option.

The ixfr-from-differences zone/template option was deprecated in favor of the zonefile-load option.

Upgrade 2.6.x to 2.7.x

Upgrading from Knot DNS version 2.6.x to 2.7.x is seamless if no obsolete configuration or module rosedb is used.

Upgrade 2.7.x to 2.8.x

Upgrading from Knot DNS version 2.7.x to 2.8.x is seamless.

However, if the previous version was migrated (possibly indirectly) from version 2.5.x, the format of the keys stored in Keys And Signature Policy Database is no longer compatible and needs to be updated.

The easiest ways to update how keys are stored in KASP DB is to modify with Keymgr version 2.7.x some of each key’s parameters in an undamaging way, e.g.:

$ keymgr example.com. list
$ keymgr example.com. set <keyTag> created=1
$ keymgr example.com. set <keyTag2> created=1
...

Knot DNS for BIND users

Automatic DNSSEC signing

Migrating automatically signed zones from BIND to Knot DNS requires copying up-to-date zone files from BIND, importing existing private keys, and updating server configuration:

  1. To obtain current content of the zone which is being migrated, request BIND to flush the zone into the zone file: rndc flush example.com.

    Note

    If dynamic updates (DDNS) are enabled for the given zone, you might need to freeze the zone before flushing it. That can be done similarly:

    $ rndc freeze example.com
    
  2. Copy the fresh zone file into the zones storage directory of Knot DNS.

  3. Import all existing zone keys into the KASP database. Make sure that all the keys were imported correctly:

    $ keymgr example.com. import-bind path/to/Kexample.com.+013+11111
    $ keymgr example.com. import-bind path/to/Kexample.com.+013+22222
    $ ...
    $ keymgr example.com. list
    

    Note

    If the server configuration file or database is not at the default location, add a configuration parameter (-c or -C).

    Note

    The server can be run under a dedicated user account, usually knot. As the server requires read-write access to the KASP database, the permissions must be set correctly. This can be achieved for instance by executing all KASP database management commands under sudo:

    $ sudo -u knot keymgr ...
    
  4. Follow Automatic DNSSEC signing steps to configure DNSSEC signing.