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Upgrade Notes

Before proceeding, it is advised to check the release notes for your PowerDNS version, as specified in the name of the distribution file.

Please upgrade to the PowerDNS Authoritative Server 4.0.0 from 3.4.2+. See the 3.X upgrade notes if your version is older than 3.4.2.

4.5.x to 4.6.0 or master

Automatic conversion of @ signs in SOA

Before version 4.5.0, PowerDNS would automatically replace @ in the SOA RNAME with ., making it easy for users to enter their hostmaster email address without having to think about syntax. However, this feature interacts badly with handling of presigned zones. In version 4.5.0, this feature was accidentally broken in the implementation of the zone cache. In 4.6.0, this automatic conversion is fully removed. If you still have @ signs in any SOA RNAMEs, 4.6.0 will serve those out literally. You can find any stray @ signs by running pdnsutil check-all-zones.

4.4.x to 4.5.0

Automatic conversion of @ signs in SOA

Before version 4.5.0, PowerDNS would automatically replace @ in the SOA RNAME with ., making it easy for users to enter their hostmaster email address without having to think about syntax. In version 4.5.0, this feature was accidentally broken in the implementation of the zone cache, and the replacement would only happen if the zone cache was disabled. Note that in 4.6.0, this automatic conversion is fully removed. If you still have @ signs in any SOA RNAMEs, 4.5.0 will serve those out literally if the zone cache is enabled.

Record type changes

The in-database format of CSYNC, IPSECKEY, NID, L32, L64, and LP records has changed from ‘generic’ format to its specialized format.

Generation of the in-database format of SVCB and HTTPS received some important bug fixes. (For these two types, you can skip the upgrade-unknown-types setting mentioned below, but we still recommend the re-transfer.)

API users might notice that replacing records of the newly supported types leaves the old TYPExx records around, even if PowerDNS is not serving them. To fix this, enable upgrade-unknown-types and replace the records; this will then delete those TYPExx records. Then, disable the setting again, because it has a serious performance impact on API operations.

On secondaries, it is recommended to re-transfer, using pdns_control retrieve ZONE, with upgrade-unknown-types enabled, all zones that have records of those types, or TYPExx, for numbers 45 and 62. Leave the setting on until all zones have been re-transferred.

Changed options

Renamed options

Various settings have been renamed. Their old names still work in 4.5.x, but will be removed in the release after it.

Changed defaults

Zone cache

Version 4.5 introduces the zone cache. The default refresh interval (zone-cache-refresh-interval) is 300, meaning that zones newly added to your backend may need a few minutes to appear. However, zones added using the API should not notice a delay.

If your backend is dynamic in what zones it does or does not offer, and thus cannot easily provide a complete list of zones every few minutes, set the interval to 0 to disable the feature.

Removed options

4.3.x to 4.4.0

Latency calculation changes

It turned out that average latency calculations in earlier versions used integers instead of floating point variables, which led to the throwing away of any data points between ‘the current average’ and 1000ms above it, instead of having those data points affecting the average. In 4.3.2 and 4.4.0, we started using floating point variables for this, which means the latency calculation is accurate now. Usually, this means you will see higher latency numbers after upgrading.

MySQL character set detection

Before 4.4.0, the gmysql backend told the MySQL (or MariaDB) client libraries to automatically detect the client character set and collation, based on the environment locale. (Look for ‘autodetect’ in https://dev.mysql.com/doc/refman/5.7/en/charset-connection.html to know more). On some systems, this autodetection makes choices that are incompatible with MySQL Server 8 defaults. On all systems, this autodetection can make choices that vary depending on how PowerDNS is started. In other words, the autodetection provides unpredictable results.

In 4.4.0, the autodetection has been removed. The MySQL/MariaDB client lib will now use its default settings, unless overridden in my.cnf, for example:

[client]
default-character-set = latin1

If you have trouble connecting to your database with 4.4.0 or up, you can override the character set in my.cnf.

Before upgrading, please check your database for any non-ASCII content. The interpretation of the non-ASCII bytes in those fields might change because of a different charset suddenly being used.

Record type changes

The in-database format of the SVCB, HTTPS and APL records has changed from ‘generic’ format to its specialized format.

API users might notice that replacing records of these types leaves the old TYPExx records around, even if PowerDNS is not serving them. To fix this, enable upgrade-unknown-types and replace the records; this will then delete those TYPExx records. Then, disable the setting again, because it has a serious performance impact on API operations.

On secondaries, it is recommended to re-transfer, using pdns_control retrieve ZONE, with upgrade-unknown-types enabled, all zones that have records of those types, or TYPExx, for numbers 42, 64, 65. Leave the setting on until all zones have been re-transferred.

PostgreSQL configuration escaping

We now correctly quote/escape Postgres connection parameters. If you used single quotes (or some other form of escaping) around your Postgres password because it contained spaces, you now need to put your unmodified, unescaped, unquoted password in your configuration.

New LMDB schema

An LMDB schema upgrade is mandatory. Please carefully read lmdb-schema-version before upgrading to 4.4.x. The new schema version is version 3.

Removed features

SOA autofilling (i.e. allowing incomplete SOAs in the database) and the API set-ptr feature, that both were deprecated in earlier releases, have now been removed. Please update your configuration and remove the following settings:

Replace them with default-soa-content, but be aware that this will only be used at zone creation time. Please run pdnsutil check-all-zones to check for incomplete SOAs.

The do-ipv6-additional-processing setting was removed. IPv6 additional processing now always happens when IPv4 additional processing happens.

4.3.1 to 4.3.2

Latency calculation changes

It turned out that average latency calculations in earlier versions used integers instead of floating point variables, which led to the throwing away of any data points between ‘the current average’ and 1000ms above it, instead of having those data points affecting the average. In 4.3.2 and 4.4.0, we started using floating point variables for this, which means the latency calculation is accurate now. Usually, this means you will see higher latency numbers after upgrading.

To be very clear, there is no performance difference between 4.3.1 and 4.3.2. The only change is in the latency calculation, which was wrong in 4.3.1 and is correct in 4.3.2. This fix was backported to 4.3.2 from 4.4.0 so that users can fairly compare the performance of 4.3.2 and 4.4.0.

4.3.0 to 4.3.1

On RHEL/CentOS 8, the gmysql backend now uses mariadb-connector-c instead of mysql-libs. This change was made because the default MySQL implementation for RHEL8 is MariaDB, and MariaDB and MySQL cannot be installed in parallel due to conflicting RPM packages. The mariadb client lib will connect to your existing MySQL servers without trouble.

Unknown record encoding (RFC 3597) has become more strict as a result of the fixes for PowerDNS Security Advisory 2020-05. Please use pdnsutil check-all-zones to review your zone contents.

The previous set of indexes for the gsqlite3 backend was found to be poor. 4.3.1 ships a new schema, and a migration:

CREATE INDEX records_lookup_idx ON records(name, type);
CREATE INDEX records_lookup_id_idx ON records(domain_id, name, type);
CREATE INDEX records_order_idx ON records(domain_id, ordername);

DROP INDEX IF EXISTS rec_name_index;
DROP INDEX IF EXISTS nametype_index;
DROP INDEX IF EXISTS domain_id;
DROP INDEX IF EXISTS orderindex;

CREATE INDEX comments_idx ON comments(domain_id, name, type);

DROP INDEX IF EXISTS comments_domain_id_index;
DROP INDEX IF EXISTS comments_nametype_index;

ANALYZE;

4.2.x to 4.3.0

NSEC(3) TTL changed

NSEC(3) records now use the negative TTL, instead of the SOA minimum TTL. See the DNSSEC TTL notes for more information.

Lua Netmask class methods changed

Netmask class methods isIpv4 and isIpv6 have been deprecated in Lua, use Netmask.isIPv4() and Netmask.isIPv6() instead. In the C++ API, these methods have been removed.

socket-dir changed

The default socket-dir has changed to include pdns in the path. It is now whatever is passed to --with-socketdir during configure (/var/run by default) plus pdns. The systemd unit-file is updated to reflect this change and systemd will automatically create the directory with the proper permissions. The packaged sysV init-script also creates this directory. For other operating systems, update your init-scripts accordingly.

Systemd service and permissions

The systemd service-file that is installed no longer uses the root user to start. It uses the user and group set with the --with-service-user and --with-service-group switches during configuration, “pdns” by default. This could mean that PowerDNS cannot read its configuration or zone-file data. It is recommended to recursively chown directories used by PowerDNS:

# For Debian-based systems
chown -R root:pdns /etc/powerdns
chown -R pdns:pdns /var/lib/powerdns

# For CentOS and RHEL based systems
chown -R root:pdns /etc/pdns
chown -R pdns:pdns /var/lib/pdns

Packages provided on the PowerDNS Repository will chown directories created by them accordingly in the post-installation steps.

New settings

  • The axfr-fetch-timeout setting has been added. This setting controls how long an inbound AXFR may be idle in seconds. Its default is 10
  • The max-generate-steps setting has been added. This sets the maximum number of steps that will be performed when loading a BIND zone with the $GENERATE directive. The default is 0, which is unlimited.

Deprecated settings

  • local-ipv6 has been deprecated and will be removed in 4.5.0. Both IPv4 and IPv6 listen addresses can now be set with local-address. The default for the latter has been changed to 0.0.0.0, ::.

Changed defaults

Schema changes

  • The new ‘unpublished DNSSEC keys’ feature comes with a mandatory schema change for all database backends (including BIND with a DNSSEC database). See files named 4.2.0_to_4.3.0_schema.X.sql for your database backend in our Git repo, tarball, or distro-specific documentation path. For the LMDB backend, please review lmdb-schema-version.
  • If you are upgrading from beta2 or rc2, AND ONLY THEN, please read pull request #8975 very carefully.

Implicit 5->7 algorithm upgrades

Since version 3.0 (the first version of the PowerDNS Authoritative Server that supported DNSSEC signing), we have automatically, silently, upgraded algorithm 5 (RSASHA1) keys to algorithm 7 (RSASHA1-NSEC3-SHA1) when the user enabled NSEC3. This has been a source of confusion, and because of that, we introduced warnings for users of this feature in 4.0 and 4.1. To see if you are affected, run pdnsutil check-all-zones from version 4.0 or up. In this release, the automatic upgrade is gone, and affected zones will break if no action is taken.

IXFR-in corruption

A bug in PowerDNS versions before 4.2.2/4.3.0 would cause wrong deletion or addition of records if IXFR deltas came in very quickly (within the query cache timeout, which defaults to 20/60 seconds). If you have zones which use inbound IXFR (in other words, the IXFR metadata item for that zone is set to 1), we strongly suggest triggering a completely fresh transfer. You could accomplish that by deleting all records in the zone with an SQL query and waiting for a fresh transfer, or (1) disabling IXFR (2) forcing a fresh transfer using pdns_control retrieve example.com (3) enabling IXFR again.

4.2.X to 4.2.3

Unknown record encoding (RFC 3597) has become more strict as a result of the fixes for PowerDNS Security Advisory 2020-05. Please use pdnsutil check-all-zones to review your zone contents.

4.X.X to 4.2.2

IXFR-in corruption

A bug in PowerDNS versions before 4.2.2/4.3.0 would cause wrong deletion or addition of records if IXFR deltas came in very quickly (within the query cache timeout, which defaults to 20/60 seconds). If you have zones which use inbound IXFR (in other words, the IXFR metadata item for that zone is set to 1), we strongly suggest triggering a completely fresh transfer. You could accomplish that by deleting all records in the zone with an SQL query and waiting for a fresh transfer, or (1) disabling IXFR (2) forcing a fresh transfer using pdns_control retrieve example.com (3) enabling IXFR again.

4.1.X to 4.2.0

  • Superslave operation is no longer enabled by default, use superslave to enable. This setting was called supermaster in some 4.2.0 prereleases.
  • The gsqlite3 backend, and the DNSSEC database for the BIND backend, have a new journal-mode setting. This setting defaults to WAL; older versions of PowerDNS did not set the journal mode, which means they used the SQLite default of DELETE.
  • Autoserial support has been removed. The change_date column has been removed from the records table in all gsql backends, but leaving it in is harmless.
  • The Generic PostgreSQL backend schema has changed: the notified_serial column type in the domains table has been changed from INT DEFAULT NULL to BIGINT DEFAULT NULL: ALTER TABLE domains ALTER notified_serial TYPE bigint USING CASE WHEN notified_serial >= 0 THEN notified_serial::bigint END;
  • Rectification after API changes is now default (default-api-rectify). If you do mutations in large zones, you may notice a slowdown.

4.1.X to 4.1.14

Unknown record encoding (RFC 3597) has become more strict as a result of the fixes for PowerDNS Security Advisory 2020-05. Please use pdnsutil check-all-zones to review your zone contents.

4.1.0 to 4.1.1

  • The Generic MySQL backend schema has changed: the notified_serial column default in the domains table has been changed from INT DEFAULT NULL to INT UNSIGNED DEFAULT NULL:
    • ALTER TABLE domains MODIFY notified_serial INT UNSIGNED DEFAULT NULL;

4.0.X to 4.1.0

  • Recursion has been removed, see the dedicated migration guide.
  • ALIAS record expansion is disabled by default, use expand-alias to enable.
  • Your LDAP schema might need to be updated, because new record types have been added (see below) and the dNSDomain2 type has been changed.
  • The LDAP Backend now supports additional Record types
    • NSEC3
    • NSEC3PARAM
    • TLSA
    • CDS
    • CDNSKEY
    • OPENPGPKEY
    • TKEY
    • URI
    • CAA

Changed options

  • experimental-lua-policy-script option and the feature itself have been completely dropped. We invite you to use PowerDNS dnsdist instead.
  • As recursion has been removed from the Authoritative Server, the allow-recursion, recursive-cache-ttl and recursor options have been removed as well.
  • default-ksk-algorithms has been renamed to default-ksk-algorithm and only supports a single algorithm name now.
  • default-zsk-algorithms has been renamed to default-zsk-algorithm and only supports a single algorithm name now.

Changed defaults

Other changes

The --with-pgsql, --with-pgsql-libs, --with-pgsql-includes and --with-pgsql-config configure options have been deprecated. configure now attempts to find the Postgresql client libraries via pkg-config, falling back to detecting pg_config. Use --with-pg-config to specify a path to a non-default pg_config if you have Postgresql installed in a non-default location.

The --with-libsodium configure flag has changed from ‘no’ to ‘auto’. This means that if libsodium and its development header are installed, it will be linked in.

The improved LDAP Backend backend now requires Kerberos headers to be installed. Specifically, it needs krb5.h to be installed.

4.0.X to 4.0.2

Changed options

Changed defaults

3.4.X to 4.0.0

Database changes

No changes have been made to the database schema. However, several superfluous queries have been dropped from the SQL backend. Furthermore, the generic SQL backends switched to prepared statements. If you use a non-standard SQL schema, please review the new defaults.

  • insert-ent-query, insert-empty-non-terminal-query, insert-ent-order-query have been replaced by one query named insert-empty-non-terminal-order-query
  • insert-record-order-query has been dropped, insert-record-query now sets the ordername (or NULL)
  • insert-slave-query has been dropped, insert-zone-query now sets the type of zone

Changed options

Several options have been removed or renamed, for the full overview of all options, see Authoritative Server Settings.

Renamed options

The following options have been renamed:

Changed defaults

Removed options

The following options are removed:

  • pipebackend-abi-version, it now a setting per-pipe backend.
  • strict-rfc-axfrs
  • send-root-referral

API

The API path has changed to /api/v1.

Incompatible change: SOA-EDIT-API now follows SOA-EDIT-DNSUPDATE instead of SOA-EDIT (incl. the fact that it now has a default value of DEFAULT). You must update your existing SOA-EDIT-API metadata (set SOA-EDIT to your previous SOA-EDIT-API value, and SOA-EDIT-API to SOA-EDIT to keep the old behaviour).

Resource Record Changes

Since PowerDNS 4.0.0 the CAA resource record (type 257) is supported. Before PowerDNS 4.0.0 type 257 was used for a proprietary MBOXFW resource record, which was removed from PowerDNS 4.0. Hence, if you used CAA records with 3.4.x (stored in the DB with wrong type=MBOXFW but worked fine) and upgrade to 4.0, PowerDNS will fail to parse this records and will throw an exception on all queries for a label with MBOXFW records. Thus, make sure to clean up the records in the DB.

In version 3.X, the PowerDNS Authoritative Server silently ignored records that have a ‘priority’ field (like MX or SRV), but where one was not in the database. In 4.X, pdnsutil check-zone will complain about this.