Share via

Redis Cache Connection Timeout for single Region

Shujing Zhang 20 Reputation points Microsoft Employee
2026-04-20T06:11:30.8166667+00:00

The Redis cache resource seems to have some issue in one of the region when the other region's Redis is working fine. It will throw Redis timeout exception for ~50% of the call which effect performance and response time. We think there is some issue with the redis resource in that specific region as the other region is working fine and we have adopt IAC that both resource's resource are deployed using the same bicep.

Could the support team help switch our redis resource to different machine? thanks

 

Azure Cache for Redis
Azure Cache for Redis

An Azure service that provides access to a secure, dedicated Redis cache, managed by Microsoft.

3 answers

Sort by: Most helpful
Most helpful Newest Oldest
  1. Shujing Zhang 20 Reputation points Microsoft Employee
    2026-05-28T01:59:10.8633333+00:00

    We tried all kind of optimization code changes but none of the works. Deploy a new redis resource and migrate to this resource fix the issue

    Was this answer helpful?

    0 comments
  2. kagiyama yutaka 3,605 Reputation points
    2026-05-19T04:00:30.5866667+00:00

    I think the step u can take is run a small redis‑cli PING/SET/GET from a same‑region VM and send those timeout samples to Support, since host check / move is handled on their side.

    Was this answer helpful?

    0 comments
  3. SAI JAGADEESH KUDIPUDI 3,470 Reputation points Microsoft External Staff Moderator
    2026-05-19T01:21:07.08+00:00

    Hi Shujing Zhang,
    We understand this situation may be impacting your Redis cache, and we truly appreciate your patience while we share our findings.

    We have identified a VNet configuration issue with the cache 'PRMerger-redis-Public-WUS'. Currently, the Redis subnet has outbound access disabled due to a Basic Load Balancer. However, Azure Cache for Redis requires outbound connectivity to communicate with essential backend services.  

    To resolve this, we kindly recommend enabling outbound access on the subnet or considering the use of Private Endpoints instead of VNet injection for improved reliability. Once this configuration is corrected, the cache should become recoverable.  

    For your reference, please follow the best practices outlined in the documentation for configuring a virtual network for Premium-tier Azure Cache for Redis. Additionally, you can review the guidance on migrating to Private Endpoints here:

    https://learn.microsoft.com/en-us/azure/azure-cache-for-redis/cache-vnet-migration
    Hope this helps. If you have any follow-up questions, please let me know. I would be happy to help.

    Was this answer helpful?

    0 comments

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.