Amazon Neptune Engine Version (2020-12-08) - Amazon Neptune
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Amazon Neptune Engine Version (2020-12-08)

As of 2020-12-08, engine version is being generally deployed. Please note that it takes several days for a new release to become available in every region.

Subsequent Patch Releases for This Release

  • Release: (2021-03-22)

  • Release: (2021-02-24)


    Release: (2020-10-12) made TLS 1.2 and HTTPS mandatory for all connections to Amazon Neptune. However, a bug in that release has allowed HTTP connections and/or outdated TLS connections to continue to work for customers who previously set a DB cluster parameter to prevent enforcement of HTTPS connections.

    That bug was fixed in patch releases and, but the fix has caused unexpected connection failures when the patches are automatically installed. For this reason, both patches have been reverted, and can only be installed manually, to give you a chance to update your setup for TLS 1.2.

    Having to use SSL/TLS for all connections to Neptune affects your connections with the Gremlin console, the Gremlin driver, Gremlin Python, .NET, nodeJs, REST APIs, and also load-balancer connections. If you have been using HTTP or an older TLS version for any or all of these up until now, you must update the relevant client and drivers and change your code to use HTTPS exclusively before updating your system to the latest patches.

New Features in This Engine Release

Improvements in This Engine Release

  • Optimized some Gremlin conditional insert patterns to avoid concurrent-modification exceptions.

Defects Fixed in This Engine Release

  • Fixed a Gremlin bug that could cause missing results for a specific pattern of queries that used the as() step.

  • Fixed a Gremlin bug that could cause errors when using the project() step nested inside another step such as union().

  • Fixed a Gremlin bug in the project() step.

  • Fixed a Gremlin bug in string-based traversal where the none() step did not work.

  • Fixed a Gremlin bug in string-based traversal where an empty map was not supported as an arguent to the inject() step.

  • Fixed a Gremlin bug in string-based traversal execution in the DFE engine where a terminal method such as toList() did not work properly.

  • Fixed a Gremlin bug that failed to close transactions which used the iterate() step in String queries.

  • Fixed a Gremlin bug that could cause queries using the is(P.gte(0)) pattern to throw an exception in some situations.

  • Fixed a Gremlin bug that could cause queries using the order().by( pattern to throw an exception in some situations.

  • Fixed a Gremlin bug that could cause queries using the addV().aggregate() pattern to give incorrect results in some situations.

  • Fixed a Gremlin bug that could cause queries using the path() step followed by the project() step pattern to throw an exception in some situations.

  • Fixed a SPARQL bug where the SUBSTR function signals an error instead of returning an empty string.

  • Fixed a bug in the DFE engine that could cause join operations in non-blocking query plans to generate incorrect results in the presence of unbound variables.

Query-Language Versions Supported in This Release

Before upgrading a DB cluster to version, make sure that your project is compatible with these query-language versions:

  • Gremlin version: 3.4.8

  • SPARQL version: 1.1

Upgrade Paths to Engine Release

Your cluster will be upgraded to this patch release automatically during your next maintenance window if you are running engine version

You can manually upgrade any previous Neptune engine release to this release.

Upgrading to This Release

Amazon Neptune is now generally available.

If a DB cluster is running an engine version from which there is an upgrade path to this release, it is eligible to be upgraded now. You can upgrade any eligible cluster using the DB cluster operations on the console or by using the SDK. The following CLI command will upgrade an eligible cluster immediately:

For Linux, OS X, or Unix:

aws neptune modify-db-cluster \ --db-cluster-identifier (your-neptune-cluster) \ --engine-version \ --apply-immediately

For Windows:

aws neptune modify-db-cluster ^ --db-cluster-identifier (your-neptune-cluster) ^ --engine-version ^ --apply-immediately

Updates are applied to all instances in a DB cluster simultaneously. An update requires a database restart on those instances, so you will experience downtime ranging from 20–30 seconds to several minutes, after which you can resume using the DB cluster.

Always test before you upgrade

When a new major or minor Neptune engine version is released, always test your Neptune applications on it first before upgrading to it. Even a minor upgrade could introduce new features or behavior that would affect your code.

Start by comparing the release notes pages from your current version to those of the targeted version to see if there will be changes in query language versions or other breaking changes.

The best way to test a new version before upgrading your production DB cluster is to clone your production cluster so that the clone is running the new engine version. You can then run queries on the clone without affecting the production DB cluster.

Always create a manual snapshot before you upgrade

Before performing an upgrade, we strongly recommend that you always create a manual snapshot of your DB cluster. Having an automatic snapshot only offers short-term protection, whereas a manual snapshot remains available until you explicitly delete it.

In certain cases Neptune creates a manual snapshot for you as a part of the upgrade process, but you should not rely on this, and should create your own manual snapshot in any case.

When you are certain that you won't need to revert your DB cluster to its pre-upgrade state, you can explicitly delete the manual snapshot that you created yourself, as well as the manual snapshot that Neptune might have created. If Neptune creates a manual snapshot, it will have a name that begins with preupgrade, followed by the name of your DB cluster, the source engine version, the target engine version, and the date.


If you are trying to upgrade while a pending action is in process, you may encounter an error such as the following:

We're sorry, your request to modify DB cluster (cluster identifier) has failed. Cannot modify engine version because instance (instance identifier) is running on an old configuration. Apply any pending maintenance actions on the instance before proceeding with the upgrade.

If you encounter this error, wait for the pending action to finish, or trigger a maintenance window immediately to let the previous upgrade complete.

For more information about upgrading your engine version, see Maintaining your Amazon Neptune DB Cluster. If you have any questions or concerns, the Amazon Support team is available on the community forums and through Amazon Premium Support.