Using the CRX2Oak Migration Tool using-the-crx-oak-migration-tool
Introduction introduction
CRX2Oak is a tool designed to migrate data between different repositories.
It can be used to migrate data from older CQ versions based on Apache Jackrabbit 2 to Oak, and it can also be used to copy data between Oak repositories.
You can download the newest version of crx2oak from the public Adobe repository at this location:
https://repo1.maven.org/maven2/com/adobe/granite/crx2oak/
Migration Use Cases migration-use-cases
The tool can be used for:
- Migrating from older CQ 5 versions to AEM 6
- Copying data between multiple Oak repositories
- Converting data between different Oak MicroKernel implementations.
Support for migrating repositories using external Blob Stores (commonly known as Data Stores) is provided in different combinations. One possible migration path is from a CRX2 repository that is using an external FileDataStore
to an Oak repository using a S3DataStore
.
The below diagram illustrates all the possible migration combinations supported by CRX2Oak:
Features features
CRX2Oak is called during AEM upgrades in a fashion in which the user can specify a predefined migration profile that automates the reconfiguration of persistence modes. This is called the quickstart mode.
It can also be run separately in case it requires more customization. However, in this mode changes are made only to the repository and any additional reconfiguration of AEM must be performed manually. This is called the standalone mode.
Another thing to note is that with the default settings in standalone mode, only the Node Store is migrated and the new repository reuses the old binary storage.
Automated Quickstart Mode automated-quickstart-mode
Since AEM 6.3, CRX2Oak is able to handle user-defined migration profiles that can be configured with all the migration options already available. This allows for both higher flexibility, and the ability to automate configuration of AEM, features that are not available if you are using the tool in standalone mode.
To switch CRX2Oak to quickstart mode, define the path to crx-quickstart folder in the AEM installation directory by way of this operating system environmental variable:
For UNIX-based systems and macOS:
export SLING_HOME="/path/to/crx-quickstart"
For Windows:
SET "SLING_HOME=/path/to/crx-quickstart"
Resume Support resume-support
The migration can be interrupted at any time, with the possibility to resume it afterwards.
Customizable Upgrade Logic customizable-upgrade-logic
Custom Java™ logic can be implemented using CommitHooks
. Custom RepositoryInitializer
classes can be implemented to initialize the repository with custom values.
Support for Memory Mapped Operations support-for-memory-mapped-operations
CRX2Oak also supports memory-mapped operations by default. Memory mapping greatly improves performance and should be used whenever possible.
Selective Migration of Content selective-migration-of-content
By default, the tool migrates the whole repository under the "/"
path. However, you have complete control over which content should be migrated.
If there is any part of the content that is not required on the new instance, you can use the --exclude-path
parameter to exclude the content and optimize the upgrade procedure.
Path Merging path-merging
If data must be copied between two repositories and you have a content path that is different on both instances, you can define it in the --merge-path
parameter. When you do, CRX2Oak copies only the new nodes to the destination repository and keeps the old ones in place.
Version Support version-support
By default, AEM creates a version of each node or page that gets modified, and store it in the repository. The versions can be then used to restore the page to an earlier state.
However, these versions are never purged even if the original page is deleted. When dealing with repositories that have been in operation for a long time, the migration may reprocess redundant data caused by orphaned versions.
A useful feature for these types of situations is the addition of the --copy-versions
parameter. It can be used to skip the version nodes during migration or copy of a repository.
You can also choose whether to copy orphaned versions by adding --copy-orphaned-versions=true
.
Both parameters also support a YYYY-MM-DD
date format, in case you want to copy versions no later than a specific date.
Open Source Version open-source-version
An open-source version of CRX2Oak is available in the form of oak-upgrade. It supports all the features except for:
- CRX2 support
- Migration profile support
- Support for automated AEM reconfiguration
See the Apache Documentation for more information.
Parameters parameters
Node Store Options node-store-options
-
--cache
: Cache size in MB (default is256
) -
--mmap
: Enable memory mapped file access for Segment Store -
--src-password:
Password for the source RDB database -
--src-user:
User for the source RDB -
--user
: User for the target RDB -
--password
: Password for the target RDB.
Migration Options migration-options
-
--early-shutdown
: Shuts down the source JCR2 repository after nodes are copied and before the commit hooks are applied -
--fail-on-error
: Forces a failure of the migration if the nodes cannot be read from the source repository. -
--ldap
: Migrates LDAP users from a CQ 5.x instance to an Oak based one. For this to work, the Identity Provider in the Oak configuration must be named ldap. For more information, see the LDAP documentation. -
--ldap-config:
Use this with the--ldap
parameter for CQ 5.x repositories that used multiple LDAP servers for authentication. You can use it to point to the CQ 5.xldap_login.conf
orjaas.conf
configuration files. The format is--ldapconfig=path/to/ldap_login.conf
.
Version Store Options version-store-options
-
--copy-orphaned-versions
: Skips copying orphaned versions. Parameters supported are:true
,false
, andyyyy-mm-dd
. Defaults totrue
. -
--copy-versions:
Copies the version storage. Parameters:true
,false
,yyyy-mm-dd
. Defaults totrue
.
Path Options path-options
--include-paths:
Comma-separated list of paths to include during copy--merge-paths
: Comma-separated list of paths to merge during copy--exclude-paths:
Comma-separated list of paths to exclude during copy.
Source Blob Store Options source-blob-store-options
-
--src-datastore:
The datastore directory to be used as a sourceFileDataStore
-
--src-fileblobstore
: The datastore directory to be used as a sourceFileBlobStore
-
--src-s3datastore
: The datastore directory to be used for the sourceS3DataStore
-
--src-s3config
: The configuration file for the sourceS3DataStore
.
Destination BlobStore Options destination-blobstore-options
-
--datastore:
The datastore directory to be used as a targetFileDataStore
-
--fileblobstore:
The datastore directory to be used as a targetFileBlobStore
-
--s3datastore
: The datastore directory to be used for the targetS3DataStore
-
--s3config
: The configuration file for the targetS3DataStore
.
Help Options help-options
-?, -h, --help:
Shows help information.
Debugging debugging
You can also enable debug information for the migration process to troubleshoot any issues that might appear during the process. You can do this differently depending on the mode you wish to run the tool in:
Other Considerations other-considerations
When migrating to a MongoDB replica set, make sure you set the WriteConcern
parameter to 2
on all connections to the Mongo databases.
You can do this by adding the w=2
parameter at the end of the connection string, like this:
java -Xmx4092m -jar crx2oak.jar crx-quickstart/repository/ mongodb://localhost:27017/aem-author?replicaset=replica1&w=2