Upgrade Archive


Neo4j 3.4 Upgrade FAQ

What is in 3.4?

All Editions:

  • Writes are now up to 5x faster for nodes with indexed string properties, thanks to native string indexes.
  • A new kernel API streamlines internal instructions.
  • New supported data types include date/time format and 3D geospatial data, enabling optimized Cypher queries for searches across time or space. The 3D geospatial search understands both Cartesian Latitude and Longitude coordinates, as well as radial distances and altitude or depth.
  • Transaction states consume less memory thanks to various efficiency improvements (including native indexing) working together.
  • Internal testing shows that Cypher runtime is 20% faster than for Neo4j 3.3 (Community Edition).

Enterprise Edition:

  • Multi-Clustering dramatically extends Neo4j scaling options by allowing users to create and manage multiple cluster-based tenants, where each operates within its own scalable Causal Cluster. With Multi-Clustering, users can logically partition graphs or oversee multiple graph database implementations across the enterprise.
  • New Cypher runtime in Enterprise Edition is 50-70% faster than Neo4j 3.3.
  • Hot backups are now twice as fast and are more robust.
  • After restart or restore, active cache warming now automatically warms the page cache to its previous operational state, getting servers back online in record time.
  • A new diagnostic utility improves the speed and accuracy of collaboration on support cases.
  • Rolling upgrades allow for updating older instances while keeping other members stable and without requiring a restart of the environment.
  • Administrators can now implement property security by name, blacklisting properties for users.

Where are the Release Notes?

Release notes for all Neo4j releases can be found here: http://neo4j.com/release-notes/

Is 3.4 an API-Breaking Release?

No. Minor releases are a place to deprecate features and functionality, which includes public APIs. However, we will not remove deprecated functionality until a major release. Note: Upgrading from a version prior to Neo4j 3.0 means that the 3.0 Upgrade FAQs apply, and this would then be a breaking release. If you are upgrading from a 2.x release, see the Upgrade FAQ Archive.

A few things you should know about 3.4:

  • The new Slotted Runtime will be used for all Cypher queries in Enterprise Edition. Use the PROFILE or EXPLAIN keywords to see which runtime is being used if unsure.
  • While Causal Clustering is the primary clustering architecture we are building on, HA still works as well.
  • Causal Clustering is still available for server only, not embedded at this time.
  • Configuration settings that changed:
    • dbms.allow_format_migration is now dbms.allow_upgrade

Migrate configuration from a pre-3.0 version

When migrating to Neo4j 3.4 from a release prior to 3.0 please note that most configuration settings have been renamed to support a more consistent naming scheme. Also note that neo4j.properties and neo4j-server.properties have been merged into a single neo4j.conf file. Since many settings have been changed between Neo4j 2.x and Neo4j 3.x, it is advisable to use the config-migrator utility to migrate the config files and settings for you. The config-migrator can be found in the bin/tools directory of Neo4j 3.x, and can be invoked with a command like: java -jar config-migrator.jar path/to/neo4j2.3 path/to/neo4j3.3. Take note of any warnings printed, and manually review the edited config files produced. The warnings will alert you to deprecated settings, or settings it did not know about (spelling mistakes, etc) that require manual intervention.

Manually Migrate Native Indexes

Beginning with 3.2, native indexes were introduced to replace Lucene indexes for specific data types for performance gain reasons. 3.3 introduced native indexes for numerics, while 3.4 implemented this feature for strings, spatial, temporal. It is important to note that the current index implementation is not migrated automatically and to benefit from the native indexes, the indexes must be manually dropped and re-created post-upgrade. The choice of index provider is controlled by the setting: dbms.index.default_schema_provider. For more information on native indexes, please refer to here.

Where in the Documentation Can I Learn More about Upgrades?

The Upgrade section of the Neo4j Operations Manual can be found here, and also covers upgrades specific to 3.4. The store upgrade happens by starting your Neo4j data store (after making the backup) with Neo4j 3.4 and the configuration dbms.allow_upgrade=true enabled in the configuration file conf/neo4j.conf

Are there any Backwards-Compatibility Options?

Yes. Cypher lets you specify what version of the Cypher compiler you would like to use. See the Operations Manual for details. So it is possible to run 2.3 queries and newer without changing them. Of course you will eventually want to upgrade your queries to take advantage of the new features in Cypher and Neo4j 3.4. Also of note is the new Causal Clustering architecture introduced in 3.1 and further improved in 3.4. Note that 3.4 will continue to support the previous Master/Slave clustering architecture available in prior versions. You can upgrade an HA system to 3.4, and save the cluster changes for a later date to simplify the process.

Is the Store Upgrade Reversible?

No, once your data store is upgraded, it cannot be rolled back. For this reason, Neo4j makes a backup of each store file as part of the upgrade to 3.4. (And as an extra precaution, it doesn’t hurt to take a second backup before you start the upgrade process. Just make sure you have enough disk space to accommodate this.) Make sure you have at least double the size of your Neo4j store available as free space on your disk, before you upgrade. After the upgrade is successful, those backup files will be removed automatically.

How Long Will the Upgrade Take?

When you initiate the upgrade of your database to 3.4 for the first time, Neo4j will run through the store files and update them to the new format. How much time this takes depends on the size of your data store. We recommend you try this out in a test environment first, to get an idea of the timing, and help you plan your upgrade. Upgrading from 3.x to 3.4 should be quite fast, while upgrading from pre-3.0 to 3.x will take longer due to the Lucene upgrade. Don’t forget though that you will first need to test your application to make sure it works! Chances are that that you may have to make some changes. How much development time required to update your code will depend on your application and which version you are upgrading from. Applications using Neo4j’s native Java APIs will be affected more than others.

When Should I Upgrade?

Upgrading to Neo4j 3.4 from a 3.x version will be very straightforward and will yield immediate performance and governance benefits. You will also have the opportunity to take advantage of new features in the realms of causal clustering, security, governance, etc. If you are in the development and planning phase, then upgrade straight away! If you are already in production with Neo4j, or have a lot of dependencies, test it first and make sure that you have the upgrade steps and dependencies sorted out before upgrading production.

Are Rolling Upgrades Supported?

Yes, but not to 3.4, only 3.4 onward. Rolling upgrades let you upgrade a cluster while it is running. While rolling upgrades between patch releases has unofficially worked in recent versions of Neo4j — Neo4j 3.4 does support rolling upgrades to future versions. This means that you will need to take an outage to upgrade to Neo4j 3.4, but once upgraded, you can rolling upgrade to future versions of Neo4j after that (ex. 3.4.x, 3.5 and onward). However, for Enterprise customers looking for guidance on minimizing the impact of this upgrade on your system, refer to the article Upgrading a Neo4j Cluster with Minimal Downtime

What Version Can I Upgrade From?

Neo4j 3.4 supports direct upgrades from 2.3 and newer. It is generally recommended to upgrade from the most recent patch of your current Neo4j release, as that is the tested upgrade path from pre-3.4 releases to 3.4. Previous versions, such as 2.2, have to be upgraded to 2.3.x first.

How Long Can I Continue Using 3.3?

3.3 will continue to be supported for at least 18 months following its release, until April 23, 2019, per the terms of your Support Agreement. Any fixes deemed applicable to the 3.3 release will be released in a 3.3.x release. As of the time of this writing, the latest stable 3.3.x release is 3.3.5. Commercial customers can view currently Supported Versions here.




Neo4j 3.3 Upgrade FAQ

What is in 3.3?

  • Write and read performance
    • Write performance of transactional writes have improved with on average 50% for typical graphs compared to Neo4j 3.2, and with over 100% compared to Neo4j 3.1.
    • Bulk writes at initial graph creation has an up to 40% smaller memory footprint
    • The new Cypher Slotted Runtime results in faster queries while using one third of the memory compared to the 3.2 Cypher Runtime
    • Least-connected load balancing strategy for clusters minimizes the effect on cluster performance when one server experiences heavy load
  • Enterprise Security
    • New support introduced for intra-cluster encryption, including multi-DC cluster communication encryption
  • Kernel improvements
    • Neo4j Enterprise now allows key configuration parameters to be changed on the fly, without needing to recycle a database instance.
    • Local Schema Locks automatically narrow the scope of locks, avoiding the need for the database to take a global schema lock when creating or changing a schema object or constraint.
    • Cache-hit ratio is now available at both a query and database level, as a new metric for helping to size one’s database cache.

Where are the Release Notes?

Release notes for all Neo4j releases can be found here: http://neo4j.com/release-notes/

Is 3.3 an API-Breaking Release?

No. Minor releases are a place to deprecate features and functionality, which includes public APIs. However, we will not remove deprecated functionality until a major release. Note: Upgrading from a version prior to Neo4j 3.0 means that the 3.0 Upgrade FAQs apply, and this would then be a breaking release. If you are upgrading from a 2.x release, see the Upgrade FAQ Archive.

A few things you should know about 3.3:

  • The new Slotted Runtime will be used for most Cypher queries. Use the PROFILE or EXPLAIN keywords to see which runtime is being used if unsure.
  • While Causal Clustering is the primary clustering architecture we are building on, HA still works as well.
  • Causal Clustering is still available for server only, not embedded at this time.
  • neo4j-shell is deprecated in favor of the new cypher-shell
  • neo4j-backup is deprecated in favor of neo4j-admin backup
  • Configuration settings that changed:
    • dbms.allow_format_migration is now dbms.allow_upgrade

Migrate configuration from a pre-3.0 version

When migrating to Neo4j 3.3 from a release prior to 3.0 please note that most configuration settings have been renamed to support a more consistent naming scheme. Also note that neo4j.properties and neo4j-server.properties have been merged into a single neo4j.conf file. Since many settings have been changed between Neo4j 2.x and Neo4j 3.x, it is advisable to use the config-migrator utility to migrate the config files and settings for you. The config-migrator can be found in the bin/tools directory of Neo4j 3.x, and can be invoked with a command like: java -jar config-migrator.jar path/to/neo4j2.3 path/to/neo4j3.3. Take note of any warnings printed, and manually review the edited config files produced. The warnings will alert you to deprecated settings, or settings it did not know about (spelling mistakes, etc) that require manual intervention.

Where in the Documentation Can I Learn More about Upgrades?

The Upgrade section of the Neo4j Operations Manual can be found here, and also covers upgrades specific to 3.3. The store upgrade happens by starting your Neo4j data store (after making the backup) with Neo4j 3.3 and the configuration dbms.allow_upgrade=true enabled in the configuration file conf/neo4j.conf

Are there any Backwards-Compatibility Options?

Yes. Cypher lets you specify what version of the Cypher compiler you would like to use. See Operations Manual for details. So it is possible to run 2.3 queries and newer without changing them. Of course you will eventually want to upgrade your queries to take advantage of the new features in Cypher and Neo4j 3.3.

Also of note is the new Causal Clustering architecture introduced in 3.1 and further improved in 3.3. Note that 3.3 will continue to support the previous Master/Slave clustering architecture available in prior versions. You can upgrade an HA system to 3.3, and save the cluster changes for a later date to simplify the process.

Is the Store Upgrade Reversible?

No, once your data store is upgraded, it cannot be rolled back. For this reason, Neo4j makes a backup of each store file as part of the upgrade to 3.3. (And as an extra precaution, it doesn’t hurt to take a second backup before you start the upgrade process. Just make sure you have enough disk space to accommodate this.) Make sure you have at least double the size of your Neo4j store available as free space on your disk, before you upgrade. After the upgrade is successful, those backup files will be removed automatically.

How Long Will the Upgrade Take?

When you initiate the upgrade of your database to 3.3 for the first time, Neo4j will run through the store files and update them to the new format. How much time this takes depends on the size of your data store. We recommend you try this out in a test environment first, to get an idea of the timing, and help you plan your upgrade. Upgrading from 3.x to 3.3 should be quite fast, while upgrading from pre-3.0 to 3.x will take longer due to the Lucene upgrade. Don’t forget though that you will first need to test your application to make sure it works! Chances are that that you may have to make some changes. How much development time required to update your code will depend on your application and which version you are upgrading from. Applications using Neo4j’s native Java APIs will be affected more than others.

When Should I Upgrade?

Upgrading to Neo4j 3.3 from a 3.x version will be very straightforward and will yield immediate performance and governance benefits. You will also have the opportunity to take advantage of new features in the realms of causal clustering, security, governance, etc. If you are in the development and planning phase, then upgrade straight away! If you are already in production with Neo4j, or have a lot of dependencies, test it first and make sure that you have the upgrade steps and dependencies sorted out before upgrading production.

Are Rolling Upgrades Supported?

No. Rolling upgrades let you upgrade a cluster while it is running. While we do our best to support rolling upgrades between patch releases — the scope and nature of the changes made in major/minor versions is such that rolling upgrades are not yet possible. However, for Enterprise customers looking for guidance on minimizing the impact of this upgrade on your system, refer to the article Upgrading a Neo4j Cluster with Minimal Downtime

What Version Can I Upgrade From?

Neo4j 3.3 supports direct upgrades from 2.3 and newer. It is generally recommended to upgrade from the most recent patch of your current Neo4j release, as that is the tested upgrade path from pre-3.3 releases to 3.3. Previous versions, such as 1.9, have to be upgraded to 2.x first.

How Long Can I Continue Using 3.2?

3.2 will continue to be supported for at least 18 months following its release, until November 11, 2018, per the terms of your Support Agreement. Any fixes deemed applicable to the 3.2 release will be released in a 3.2.x release. As of the time of this writing, the latest stable 3.2.x release is 3.2.6. Commercial customers can view currently Supported Versions here.




Neo4j 3.2 Upgrade FAQ

What is in 3.2?

  • Multi-data center support in Enterprise Edition:
    • Run Causal Clusters conveniently across geographically separated data centers
    • Tiered Read Replicas allow larger scale across data center groups by replicating data from Read Replicas rather than Core Servers across the WAN
    • Driver Bolt+routing support for multi-data center configuration
  • Causal Cluster improvements
    • Causal Cluster-aware drivers allow the client to define the level of consistency needed: Read my own writes vs. read from any instance
  • Production governance features in Enterprise Edition:
    • Node Keys allow you to specify a set of properties that are mandatory and unique for a given label
    • Security: Kerberos support via Neo4j Kerberos Add-On
    • Improved query monitoring and administration
      • List queries shows active locks and resource utilization per query
      • Derived “page cache-hit ratio” shows how efficient a query is in terms of utilizing page caching for optimal performance
  • Native performance improvements
    • New native label index replaces Lucene indexing for labels (30-300% performance improvement on writing/deleting labelled nodes)
    • Introduced composite indexes for index lookups on multiple properties for a node
    • Compiled runtime for basic cypher queries improves performance in Enterprise Edition
  • Neo4j Browser was re-written with a more flexible JavaScript framework. This led to new Cypher editor improvements, including syntax highlighting and Cypher auto-completion
  • IBM Power8 CAPI Flash Support for causal clustering (Enterprise Edition)

Where are the Release Notes?

Release notes for all Neo4j releases can be found here: http://neo4j.com/release-notes/

Is 3.2 an API-Breaking Release?

No. Minor releases are a place to deprecate features and functionality, which includes public APIs. However, we will not remove deprecated functionality until a major release. Note: Upgrading from a version prior to Neo4j 3.0 means that the 3.0 Upgrade FAQs apply, and this would then be a breaking release. If you are upgrading from a 2.x release, see the Upgrade FAQ Archive.

A few things you should know about 3.2:

  • The new Compiled Runtime will be used for any Cypher queries that qualify, and it is only covering ~15% of possible queries, so use the PROFILE or EXPLAIN keywords to see which runtime is being used if unsure.
  • While Causal Clustering is the primary clustering architecture we are building on, HA still works as well.
  • Causal Clustering is still available for server only, not embedded at this time.
  • There is now an official RPM package distribution for Neo4j
  • neo4j-shell is deprecated in favor of the new cypher-shell
  • neo4j-backup is deprecated in favor of neo4j-admin backup

Migrate configuration from a pre-3.0 version

When migrating to Neo4j 3.2 from a release prior to 3.0 please note that most configuration settings have been renamed to support a more consistent naming scheme. Also note that neo4j.properties and neo4j-server.properties have been merged into a single neo4j.conf file. Since many settings have been changed between Neo4j 2.x and Neo4j 3.x, it is advisable to use the config-migrator utility to migrate the config files and settings for you. The config-migrator can be found in the bin/tools directory of Neo4j 3.x, and can be invoked with a command like: java -jar config-migrator.jar path/to/neo4j2.3 path/to/neo4j3.2. Take note of any warnings printed, and manually review the edited config files produced. The warnings will alert you to deprecated settings, or settings it did not know about (spelling mistakes, etc) that require manual intervention.

Where in the Documentation Can I Learn More about Upgrades?

The Upgrade section of the Neo4j Operations Manual can be found here, and also covers upgrades specific to 3.2. The store upgrade happens by starting your Neo4j data store (after making the backup) with Neo4j 3.2 and the configuration dbms.allow_format_migration=true enabled in the configuration file conf/neo4j.conf

Are there any Backwards-Compatibility Options?

Yes. Cypher lets you specify what version of the Cypher compiler you would like to use. See Operations Manual for details. So it is possible to run your 2.x queries without changing them. Of course you will eventually want to upgrade your queries to take advantage of the new features in Cypher and Neo4j 3.2.

Also of note is the new Causal Clustering architecture introduced in 3.1 and further improved in 3.2. Note that 3.2 will continue to support the previous Master/Slave clustering architecture available in 3.0 and prior versions. You can upgrade to 3.2, and save the cluster changes for a later date to simplify the process.

Is the Store Upgrade Reversible?

No, once your data store is upgraded, it cannot be rolled back. For this reason, Neo4j makes a backup of each store file as part of the upgrade to 3.2. (And as an extra precaution, it doesn’t hurt to take a second backup before you start the upgrade process. Just make sure you have enough disk space to accommodate this.) Make sure you have at least double the size of your Neo4j store available as free space on your disk, before you upgrade. After the upgrade is successful, those backup files will be removed.

How Long Will the Upgrade Take?

When you initiate the upgrade of your database to 3.2 for the first time, Neo4j will run through the store files and update them to the new format. How much time this takes depends on the size of your data store. We recommend you try this out in a test environment first, to get an idea of the timing, and help you plan your upgrade. Upgrading from 3.x to 3.2 should be quite fast, while upgrading from pre-3.0 to 3.x will take longer due to the Lucene upgrade. Don’t forget though that you will first need to test your application to make sure it works! Chances are that that you may have to make some changes. How much development time required to update your code will depend on your application. Applications using Neo4j’s native Java APIs will be affected more than others.

When Should I Upgrade?

Upgrading to Neo4j 3.2 from a 3.x version will be very straightforward and will yield immediate performance and governance benefits. You will also have the opportunity to take advantage of new features in the realms of causal clustering, security, governance, etc. If you are in the development and planning phase, then upgrade straight away! If you are already in production with Neo4j, or have a lot of dependencies, test it first and make sure that you have the upgrade steps and dependencies sorted out before upgrading production.

Are Rolling Upgrades Supported?

No. Rolling upgrades let you upgrade a cluster while it is running. While we do our best to support rolling upgrades between patch releases — the scope and nature of the changes made in major/minor versions is such that rolling upgrades are not possible. However, for Enterprise customers looking for guidance on minimizing the impact of this upgrade on your system, refer to the article Upgrading a Neo4j Cluster with Minimal Downtime

What Version Can I Upgrade From?

Neo4j 3.2 supports direct upgrades from 2.0 and newer. It is generally recommended to upgrade from the most recent patch, as that is the tested upgrade path from pre-3.2 releases to 3.2. Previous versions, such as 1.9, have to be upgraded to 2.x first.

How Long Can I Continue Using 3.1?

3.1 will continue to be supported for at least 12 months following its release (December 14th, 2016) per the terms of your Support Agreement. Any fixes deemed applicable to the 3.1 release will be released in a 3.1.x release. As of the time of this writing, the latest stable 3.1.x release is 3.1.4.


Neo4j 3.1 Upgrade FAQ

What is in 3.1?
  • New Clustering Technology based on state-of-the-art Raft protocol:
    • Cluster-aware stack with built-in load balancing
    • Causal consistency enabling applications to decide on cost/consistency tradeoff at query time
  • New Security Foundation ensuring that authenticated users and applications can perform only authorized actions on data graph stored in Neo4j:
    • Role-Based Access Control for built-in native and federated users (via LDAP connector)
    • Sub-graph authorization achievable via User-Defined Procedures
    • Query listing and termination using :queries command in Neo4j Browser
    • Security event logging
  • Database Kernel and Operations Advances:
    • New execution guard to terminate long-running, end-user queries
    • Ability to reallocate space from deleted records while the cluster is online
    • New command line tools: cypher-shell and improved neo4j-admin
  • Schema Viewer: Displays the graph model at the current point in time
  • IBM Power8 CAPI Flash Support: Enables ultra-large in-memory graphs 

Where are the Release Notes?

Release notes for all Neo4j releases can be found here: http://neo4j.com/release-notes/

Is 3.1 an API-Breaking Release?

No. Minor releases are a place to deprecate features and functionality, which includes public APIs. However, we will not remove deprecated functionality until a major release. Note: upgrading from a version prior to Neo4j 3.0 means that the 3.0 Upgrade FAQs apply, and this would then be a potential breaking release. If you are upgrading from a 2.x release, see the 3.0 Upgrade FAQs below.

A few things you should know about 3.1:

  • While Causal Clustering is introduced, HA still works as well.
  • Causal Clustering is available for server only, not embedded at this time.
  • To keep local security credentials in sync across a cluster, use rsync as described in this KB (Neo4j support portal access only): https://support.neo4j.com/hc/en-us/articles/236060187-Cluster-synchronization-of-neo4j-native-security
  • The neo4j.conf and neo4j-wrapper.conf are merged in 3.1. neo4j-wrapper.conf is deprecated.
    • See this KB (public access) for example script: https://neo4j.com/developer/kb/manually-merging-neo4jwrapperconf-into-neo4jconf-in-neo4j-31/
  • neo4j-shell is deprecated in favor of the new cypher-shell 

Migrate configuration

When upgrading to Neo4j 3.1 from Neo4j 3.0, the conf/neo4j.conf and conf/neo4j-wrapper.conf files have now been merged into one. The configuration settings have not changed, so it is simply a matter of copying the contents of conf/neo4j-wrapper.conf, pasting into the end of the conf/neo4j.conf file, and then removing conf/neo4j-wrapper.conf. Use the script in the KB entitled Manually Merging neo4j-wrapper.conf into neo4j.conf in Neo4j 3.1 to automate this merge. Note: conf/neo4j-wrapper.conf will be deprecated, and not removed yet, so will still work for backward compatibility.

When migrating to Neo4j 3.1 from a release prior to 3.0 please note that most configuration settings have been renamed to support a more consistent naming scheme. Also note that neo4j.properties and neo4j-server.properties have been merged into a single neo4j.conf file. Since many settings have been changed between Neo4j 2.x and Neo4j 3.0, it is advisable to use the config-migrator utility to migrate the config files and settings for you. The config-migrator can be found in the bin/tools directory of Neo4j 3.0, and can be invoked with a command like: java -jar config-migrator.jar path/to/neo4j2.3 path/to/neo4j3.0. Take note of any warnings printed, and manually review the edited config files produced. The warnings will alert you to deprecated settings, or settings it did not know about (spelling mistakes, etc) that require manual intervention.  Also note that the following configuration settings have been deprecated between Neo4j 3.0 and 3.1: dbms.index_sampling.buffer_size

Where in the Documentation Can I Learn More about Upgrades?

The Upgrade section of the Neo4j Operations Manual can be found here, and also covers upgrades specific to 3.1. The store upgrade happens by starting your Neo4j data store (after making the backup) with Neo4j 3.1 and the configuration dbms.allow_format_migration=true enabled in the configuration file conf/neo4j.conf

Are there any Backwards-Compatibility Options?

Yes. Cypher lets you specify what version of the Cypher compiler you would like to use. See Operations Manual for details. So it is possible to run your 2.x queries without changing them. Of course you will eventually want to upgrade your queries to take advantage of the new features in Cypher and Neo4j 3.1.

Also of note is the new Causal Clustering architecture introduced in 3.1. Note that 3.1 will continue to support the previous Master/Slave clustering architecture available in 3.0 and prior versions. You can upgrade to 3.1, and save the cluster changes for a later date to simplify the process.

Is the Store Upgrade Reversible?

No, once your data store is upgraded, it cannot be rolled back. For this reason, Neo4j makes a backup of each store file as part of the upgrade to 3.1. (And as an extra precaution, it doesn’t hurt to take a second backup before you start the upgrade process. Just make sure you have enough disk space to accommodate this.) Make sure you have at least double the size of your Neo4j store available as free space on your disk, before you upgrade. After the upgrade is successful, those backup files will be removed.

How Long Will the Upgrade Take?

When you initiate the upgrade of your database to 3.1 for the first time, Neo4j will run through the store files and update them to the new format. How much time this takes depends on the size of your data store. We recommend you try this out in a test environment first, to get an idea of the timing, and help you plan your upgrade. Don’t forget though that you will first need to test your application to make sure it works! Chances are that that you may have to make some changes. How much development time required to update your code will depend on your application. Applications using Neo4j’s native Java APIs will be affected more than others.

When Should I Upgrade?

If you are planning a new release of your app, and adding new features, then we recommend you upgrade now: since you are likely to save a lot of time with the new features. Even if you aren’t adding features, we suggest you start planning your upgrade soon, in the coming months, as the 2.3 and prior releases will now be going into maintenance mode. As far as when to schedule your upgrade? Upgrading an already-running application to 3.1 just for the sake of it may not yield huge benefits right now. One good reason to start planning an upgrade besides new features is the upcoming 3.1 release. Neo4j 3.1 is planned to be a minor/API-compatible release of Neo4j 3.x, focused primarily on scalability and security. Neo4j 3.1 is expected mid-late 2016, and like 3.0, will require a store upgrade. Customers not in a hurry to upgrade, and/or seeking to minimize their Neo4j upgrade overhead in 2016, might want to start developing on 3.0 and go live with 3.1. As always, we encourage you to contact Support to discuss your actual situation. We are happy to offer advice as to when to time your upgrade.

Are Rolling Upgrades Supported?

No. Rolling upgrades let you upgrade a cluster while it is running. While we do our best to support rolling upgrades between patch releases – the scope and nature of the changes made in major/minor versions is such that rolling upgrades are not possible. However, for Enterprise customers looking for guidance on minimizing the impact of this upgrade on your system, refer to the article Upgrading a Neo4j Cluster with Minimal Downtime

What Version Can I Upgrade From?

Neo4j 3.1 supports direct upgrades from 2.0 and newer. It is generally recommended to upgrade from the most recent patch, as that is the tested upgrade path from pre-3.1 releases to 3.1. Previous versions, such as 1.9, have to be upgraded to 2.x first.

How Long Can I Continue Using 3.0?

3.0 will continue to be supported for at least 12 months following its release (April 26, 2016) per the terms of your Support Agreement. Any fixes deemed applicable to the 3.0 release will be released in a 3.0.x release. As of the time of this writing, the latest stable 3.0.x release is 3.0.7.


Neo4j 3.0 Upgrade FAQ

What is in 3.0?

Neo4j 3.0 substantially improves installation, application development, and operational management. On disk, Neo4j has a reorganized directory layout which is easier to understand and work with; take note of the new locations and names. Application development has been vastly simplified and optimized, featuring a single, coherent, high-speed programming interface called Bolt. With Cypher’s new ability to mix queries and calls to Java Stored Procedures, even Java developers will love working over-the-wire.

Where are the Release Notes?

Release notes for all Neo4j releases can be found here: http://neo4j.com/release-notes/

Is 3.0 an API-Breaking Release?

Yes. Major releases are the time when we remove features that were marked deprecated in earlier releases. Further: to benefit from the upgrade to Neo4j 3.0, you will need to change your code to take advantage of the new features, such as the new language drivers over the Bolt protocol.

A few things you should know about 3.0:

    • To use Neo4j 3.0, please install Java 8, preferably the OpenJDK 8, Oracle Java 8 or IBM Java 8. Install at least the full Java Runtime Environment (JRE) with command-line tools.
    • The store format for Neo4j Enterprise has changed considerably, as is the case with a major release. See section on Is the Store Upgrade Reversible for more details.
    • Lucene has been upgraded from 3.6.2 to 5.4.0. As a result, all indexes will be rebuilt on upgrade, which means the upgrade will take some additional time.
    • The directory structure and configuration parameters have been refactored. Please make yourself familiar with the new location and names of files.

Migrate configuration

When migrating to Neo4j 3.0 from a previous release, please note that most configuration settings have been renamed to support a more consistent naming scheme. Also note that neo4j.properties and neo4j-server.properties have been merged into a single neo4j.conf file. Since many settings have been changed between Neo4j 2.x and Neo4j 3.0, it is advisable to use the config-migrator utility to migrate the config files and settings for you. The config-migrator can be found in the bin/tools directory of Neo4j 3.0, and can be invoked with a command like: java -jar config-migrator.jar path/to/neo4j2.3 path/to/neo4j3.0. Take note of any warnings printed, and manually review the edited config files produced. The warnings will alert you to deprecated settings, or settings it did not know about (spelling mistakes, etc) that require manual intervention. Also note that the following configuration settings have been removed between Neo4j 2.3 and 3.0:
consistency_check_execution_order consistency_check_report_file logging.threshold_for_rotation neo_store org.neo4j.server.database.location org.neo4j.server.db.tuning.properties org.neo4j.server.http.log.config org.neo4j.server.http.unsafe.content_log.enabled org.neo4j.server.properties org.neo4j.server.webadmin.rrdb.location org.neo4j.server.webserver.https.keystore.location org.neo4j.server.webserver.statistics relationship_grab_size store.internal_log.location wrapper.user
 

Where in the Documentation Can I Learn More about Upgrades?

The Upgrade section of the Neo4j Operations Manual can be found here, and also covers upgrades specific to 3.0. The store upgrade happens by starting your Neo4j data store (after making the backup) with Neo4j 3.0 and the configuration dbms.allow_format_migration=true enabled in the configuration file conf/neo4j.conf.

Are there any Backwards-Compatibility Options?

Yes. Cypher lets you specify what version of the Cypher compiler you would like to use. See Operations Manual for details. So it is possible to run your 2.x queries without changing them. Of course you will eventually want to upgrade your queries to take advantage of the new features in Cypher and Neo4j 3.0.

Is the Store Upgrade Reversible?

No, once your data store is upgraded, it cannot be rolled back. For this reason, Neo4j makes a backup of each 2.x store file as part of the upgrade to 3.0. (And as an extra precaution, it doesn’t hurt to take a second backup before you start the upgrade process.) Make sure you have at least double the size of your Neo4j store available as free space on your disk, before you upgrade. After the upgrade is successful, those backup files will be removed. There is a new store format option to remove the upper limits for numbers of nodes, relationships, and properties in a single graph. The default format is the previous, standard format. To enable the new high limit format, set dbms.record_format=high_limit in conf/neo4j.conf. Note: Once you start the database with the high limit format, you cannot revert back!

How Long Will the Upgrade Take?

When you initiate the upgrade of your database to 3.0 for the first time, Neo4j will run through the store files and update them to the new format. How much time this takes depends on the size of your data store. We recommend you try this out in a test environment first, to get an idea of the timing, and help you plan your upgrade. Don’t forget though that you will first need to test your application to make sure it works! Chances are that that you will have to make some changes. How much development time required to update your code will depend on your application. Applications using Neo4j’s native Java APIs will be affected more than others. Beyond the changes required to upgrade, leveraging new features such as the new language drivers and Bolt binary protocol, will may take more or less time depending on your application.

When Should I Upgrade?

If you are planning a new release of your app, and adding new features, then we recommend you upgrade now: since you are likely to save a lot of time with the new features. Even if you aren’t adding features, we suggest you start planning your upgrade soon, in the coming months, as the 2.2 and prior releases will now be going into maintenance mode. As far as when to schedule your upgrade? Upgrading an already-running application to 3.0 just for the sake of it may not yield huge benefits right now. One good reason to start planning an upgrade besides new features is the upcoming 3.1 release. Neo4j 3.1 is planned to be a minor/API-compatible release of Neo4j 3.x, focused primarily on scalability and security. Neo4j 3.1 is expected mid-late 2016, and like 3.0, will require a store upgrade. Customers not in a hurry to upgrade, and/or seeking to minimize their Neo4j upgrade overhead in 2016, might want to start developing on 3.0 and go live with 3.1. As always, we encourage you to contact Support to discuss your actual situation. We are happy to offer advice as to when to time your upgrade.

Are Rolling Upgrades Supported?

No. Rolling upgrades let you upgrade a cluster while it is running. While we do our best to support rolling upgrades between patch releases – the scope and nature of the changes made in major/minor versions is such that rolling upgrades are not possible. However, for Enterprise customers looking for guidance on minimizing the impact of this upgrade on your system, refer to the article Upgrading a Neo4j Cluster with Minimal Downtime.

What Version Can I Upgrade From?

Neo4j 3.0 supports direct upgrades from 2.0 and newer. It is generally recommended to upgrade from a recent patch, as that is the tested upgrade path from pre-3.0 releases to 3.0. Previous versions, such as 1.9, have to be upgraded to 2.x first.

How Long Can I Continue Using 2.3?

2.3 will continue to be supported for at least 6 months in parallel to 3.0, according to the terms of your Support Agreement. Any critical fixes deemed important enough will be released in a 2.3.x release. As of the time of this writing, the latest stable 2.3.x release is 2.3.3.

Faster than 2.3?

One major improvement in 3.0 is the introduction of unified language drivers and the Bolt binary protocol. In addition to giving a clean, concise and controlled driver interface across languages, the Bolt protocol is an improvement over the REST API in terms of overhead and performance. In addition, 3.0 introduces a cost-based optimizer for write queries, to complement the cost-based optimizer for reads introduced in Neo4j 2.2. You can expect write queries to particularly benefit from this release. Also, if you handled reads and writes in separate transactions to make sure reads used the cost-based planner, that extra code is no longer needed. On top of that, Neo4j 3.0 includes an upgrade of Lucene to version 5, so index writes are optimized.