Magento 2.4.9 is GA

The most operationally significant change in Magento 2.4.9 isn't OpenSearch 3 or the new PHP version requirements: it's that Adobe has officially switched the cache and session store from Redis to Valkey.

The backstory: in March 2024, Redis Inc. changed Redis's licence from BSD to a dual-licence model (Redis Source Available License and Server Side Public License). This is incompatible with many open-source distribution models and broke long-standing arrangements with cloud providers and Linux distributions. In April 2024, the Linux Foundation forked the last BSD-licensed version of Redis (Redis 7.2.4) into a new project called Valkey, backed by AWS, Google Cloud, Oracle, Ericsson and Snap. Valkey is a drop-in replacement for Redis at the wire-protocol level (the same commands, the same client libraries, the same data structures) but with a fully open BSD-3 licence and a foundation-backed governance model.

Magento 2.4.9 makes the switch official: the CLI tooling now uses Valkey commands, Adobe's documentation has been updated to reference Valkey rather than Redis, and the recommended cache stack ships Valkey 9 by default. Adobe no longer lists Redis as supported for 2.4.9. Redis often still runs because the protocol is the same, but a store on Redis sits outside the tested configuration.

What this means in practice depends on what you're currently running. If your Magento store is on Redis 7.2 or earlier, you can swap in Valkey 9 at your next convenient maintenance window: RDB files copy across directly because the formats are compatible. If you've already upgraded to Redis 7.4 or later, the path is harder: Redis 7.4 introduced internal format changes that Valkey cannot read, so you must migrate using replication (configure Valkey as a replica of your Redis instance, wait for full sync, then cut over). EveryHost handles both migration paths as part of managed hosting onboarding.

Magento 2.4.9 adds support for OpenSearch 3.x, and Adobe tests 2.4.9 only with OpenSearch 3: OpenSearch 2.x and Elasticsearch are no longer listed. OpenSearch 3 brings improved relevance scoring, faster aggregation performance, and a number of bug fixes around catalogue search behaviour. The latest 2.4.7 and 2.4.8 patches support OpenSearch 3 as well, so you can move search before the Magento upgrade.

The trade-off is that OpenSearch 3 introduces index format changes that aren't backward-compatible with OpenSearch 2, so moving to it means a full Magento reindex. For large catalogues this can be the longest-running step in the entire 2.4.9 migration. Budget time accordingly.

PHP 8.2 is removed. Magento 2.4.9 runs on PHP 8.5, and PHP 8.3 is no longer supported. PHP 8.4 is allowed only while you upgrade, not for production. PHP 8.5 only reached stability in late 2025; expect a handful of less-actively-maintained extensions to need updates before they're 8.5-ready.

Database versions are strict. MySQL 8.4 or MariaDB 12.3, Adobe's recommended engines for 2.4.9 (Adobe also lists MariaDB 11.8, for cloud only). Older versions (MySQL 8.0, MariaDB 10.6, MariaDB 10.11) are no longer supported. The upgrade will fail at the schema validation step if your engine isn't current, so this is the first thing to check before scheduling any upgrade work.

Apache ActiveMQ Artemis is now a supported message queue, alongside RabbitMQ. For stores running heavy asynchronous workloads (Inventory Management, order processing, indexing queues), Artemis can be a more predictable choice than RabbitMQ under load.

Adobe has shipped 581 bug fixes in 2.4.9. A handful are operationally significant for any store that's been running 2.4.x for a while:

• FPT infinite-loading cart fix. Stores using Fixed Product Tax with certain quote-rule combinations could get a checkout-cart loop that left customers stuck on a spinning page. Resolved in 2.4.9.
• Duplicate FPC entries from query parameters. Pages were being cached multiple times when query-string parameter order varied, bloating Varnish memory. The full-page-cache key generation now normalises parameter order.
• Inventory Management performance improvements for multi-source stores. Source assignment queries that previously took multiple seconds on stores with 5+ sources now complete in milliseconds.
• Checkout reliability under concurrent load. Race conditions in order placement during peak traffic (Black Friday-style bursts) have been hardened, reducing the rate of order-creation failures.

If you're planning a 2.4.9 upgrade in the next 60–90 days, run through these in order:

1. Audit your database engine version. 2.4.9 needs MySQL 8.4 or MariaDB 12.3. A store on the latest 2.4.8 patch with MySQL 8.4 is already there. The latest 2.4.7 patch supports neither, so a 2.4.7 store changes its database on a staging copy during the upgrade, not before: see our 2.4.7 to 2.4.9 upgrade guide.
2. Check PHP version. PHP 8.5 is the target, with 8.4 allowed only while you upgrade. The latest 2.4.7 patch supports neither, so a 2.4.7 store also changes PHP on staging during the upgrade.
3. Inventory every installed Magento extension and check vendor compatibility statements for 2.4.9 specifically. Extensions that haven't been updated since 2.4.7 will likely need work.
4. Decide on Redis-to-Valkey strategy. If on Redis 7.2 or earlier, plan a swap-in. If on Redis 7.4+, plan a replication-based migration.
5. Move search to OpenSearch 3. Adobe lists only OpenSearch 3 for 2.4.9, so OpenSearch 2.x and Elasticsearch have to be replaced before or during the upgrade.
6. Build a staging environment on the target stack (PHP 8.5, MySQL 8.4, Valkey 9, OpenSearch 3). Run the Magento 2.4.9 upgrade end-to-end on staging.
7. Run a full functional test pass: checkout, payments, email, search, admin, reports, extensions. Anything broken is a blocker, not a "we'll fix it later".
8. Schedule the cutover with DNS TTL pre-lowered, once staging is signed off.

Coming from 2.4.7? Our guide to the Magento 2.4.7 to 2.4.9 upgrade order explains which of these can change before the upgrade and which have to change with it.

EveryHost managed Magento hosting is ready for 2.4.9 on every front:

• Valkey 9 available as a drop-in replacement for Redis, with replication-based migration support for stores on Redis 7.4+
• OpenSearch 3 ready, with OpenSearch 2.x still available for stores on Magento versions before 2.4.9
• PHP 8.5 in production, with PHP 8.4 available while you upgrade
• MySQL 8.4 and MariaDB 12.3, Adobe's recommended engines, fully supported and patched
• Free Magento migration includes the Redis-to-Valkey transition for stores moving to EveryHost as part of a 2.4.9 upgrade

EveryHost is a Magento Open Source specialist. We've been preparing for the 2.4.9 stack changes since the beta was published in March. If you'd like to plan a 2.4.9 upgrade with UK-based Magento engineers, call 0333 577 6191 or use the contact form.