Does upgrading Azure Cache for Redis from V4 to V6 will impact to website

Question

Microsoft will be updating to v 6.0. will there be any impact on our portal after the upgrade?

Answer 1

Hi
Martunis Mukhtar •,

Welcome to Microsoft Q&A forum and thanks for using Azure Services.

As I understand, you want to know if upgrading Azure Cache for Redis from V4 to V6 will impact to website.

See below FAQ which might help:

Is my application affected during upgrade?

Your application sees a connection blip that lasts a few seconds. Your application should retry commands appropriately when experiencing connectivity errors. Fore more information, see Best practices for connection resilience.

Typically, the upgrade operation takes about 20 minutes per cache node, but it could take longer if the cache is under high server load.

Note:

Standard and Premium caches are fully functional and available during the upgrade process, but your applications see a connection blip for a few seconds. Basic caches are unavailable during the upgrade and all data will be lost.

During the upgrade process, the replica node of your cache is first upgraded to run Redis version 6. The upgrade replica node then takes over as the primary node for your cache while the former primary node reboots to take on the role of replica. This process is exactly like the patching process described in How does patching occur?.

Redis version 6 is compatible with version 4 and applications should continue to function seamlessly after the version upgrade.

If you don't upgrade your Redis 4 cache by June 30, 2023, the cache is automatically upgraded to version 6. If you have a maintenance window scheduled for your cache, the upgrade happens during the maintenance window. Geo-replicated Redis 4 caches will be retired on August 30, 2023.

Also, Caches can't be upgraded while they have a geo-replication link.

1. First, you must unlink the caches temporarily.
2. Upgrade both your caches.
3. Then relink them.

Hope this information helps. Do let us know if you have further queries. Thank you.

Answer 2

Hi Avi •,

On June 30, 2023, we'll retire version 4 for Azure Cache for Redis instances. Before that date, you need to upgrade any of your cache instances to version 6.

• All cache instances running Redis version 4 after June 30, 2023 will be upgraded automatically.
• All cache instances running Redis version 4 that have geo-replication enabled will be upgraded automatically after August 30, 2023.

We recommend that you upgrade your caches on your own to accommodate your schedule and the needs of your users to make the upgrade as convenient as possible.

The open-source Redis version 4 was released several years ago and is now retired. Version 4 no longer receives critical bug or security fixes from the community. Azure Cache for Redis offers open-source Redis as a managed service on Azure. To stay in sync with the open-source offering, we'll also retire version 4. Microsoft continues to backport security fixes from recent versions to version 4 until retirement. We encourage you to upgrade your cache to version 6 sooner, so you can use the rich feature set that Redis version 6 has to offer. For more information, See the Redis 6 GA announcement for more details.

To upgrade your version 4 Azure Cache for Redis instance, see How to upgrade an existing Redis 4 cache to Redis 6. If your cache instances have geo-replication enabled, you’re required to unlink the caches before upgrade.

Refer: https://learn.microsoft.com/en-us/azure/azure-cache-for-redis/cache-retired-features#what-happens-to-my-cache-if-i-dont-upgrade-to-redis-version-6-by-june-30-2023

Let us know if you have further queries. Thanks