RedisMOVEDRedirect on Amazon ElastiCache, what causes it and how to fix
| Service | Amazon ElastiCache |
|---|---|
| Cloud | Amazon Web Services (AWS) |
| Guide type | Procedure |
| Skill level | Intermediate to advanced |
| Time | 15 - 60 minutes depending on account size |
RedisMOVEDRedirect on Amazon ElastiCache, what causes it and how to fix on Amazon ElastiCache sits in the most-reported issues list across r/aws, AWS re:Post, and StackOverflow. The recovery path is mostly known, the AWS docs just bury it under three layers of conceptual material.
What redismovedredirect on amazon elasticache, what causes it and how to fix actually involves on Amazon ElastiCache
The RedisMOVEDRedirect error from AWS typically surfaces with the message "MOVED redirect to wrong shard endpoint". The error code itself is what you grep for in AWS re:Post or in AWS Support cases, not the human-readable line.
On Amazon ElastiCache, this most often comes from one of three causes: a missing or restrictive IAM permission, a service-level limit you have hit, or a transient AWS-side capacity issue. The fix path differs by which.
The rest of this page is the structured fix path. Start with diagnose, then remediation, then the automation options so you do not have to do this by hand the next time it surfaces. Verify and safety sections at the end are the discipline that keeps the fix from regressing in production.
Identify
Check CloudWatch Logs for the calling service. Lambda, ECS, EKS, Step Functions, API Gateway, and most managed services write detailed traces to CloudWatch Logs under predictable log group names. Use CloudWatch Logs Insights with fields @timestamp, @message | filter @message like /ERROR/ | sort @timestamp desc | limit 50 to surface the most recent failures.
Diff against last known good. The last config change you made is the cause about three quarters of the time, even when the change should not have mattered. Use AWS Config history (or your Terraform / CloudFormation drift report) to see the actual delta between the resource state when it worked and when it broke. The change you remember is often not the only change that happened.
Run aws sts get-caller-identity first. About one in five 'why does this not work' tickets are actually 'I am in the wrong account' or 'my session expired and the SDK is using stale creds'. The 5-second sanity check costs nothing and saves real time when the answer is that simple.
Solution-focused remediation path
Most Amazon ElastiCache failures fall into one of three buckets: IAM permission gap, networking path break (security group, NACL, or VPC endpoint policy), or service-limit / quota hit. Run that mental triage first - it covers around 80 percent of real-world cases. If the failure does not fit any of the three, it is likely a service-side regression worth opening a re:Post or support ticket for.
For IAM and STS issues, the timing matters. STS sessions can take up to 60 seconds to propagate after creation. The first call right after assume-role can fail with a permission error even when the policy is correct. Add a small retry with backoff before treating the first failure as definitive.
When the failure happens in production but not in dev, do not just compare the IAM policy. Compare the SCP / RCP at the OU level, the permission boundary on the role, and the resource-based policy on the target. One of those is almost always different between accounts. AWS Config conformance packs make this comparison routine.
Automate this fix so you do not do it twice
Wire the fix into EventBridge for self-healing
If the failure mode is recurring, automate the remediation instead of the diagnosis. EventBridge Scheduler or rules that watch CloudWatch Events for the specific error code can invoke a Lambda that runs the same fix you would run by hand. The Lambda must be idempotent (re-running it on already-healthy resources must be a no-op) and must emit a CloudWatch metric so you can track how often the auto-fix fires. A spike in auto-fix invocations is itself a signal worth alerting on.
# EventBridge rule pattern (JSON)
{ "source": ["aws.elasticache"], "detail-type": ["AWS API Call via CloudTrail"], "detail": { "errorCode": ["AccessDenied", "ThrottlingException"] }
}Add a CloudWatch alarm so you know next time
The cheapest way to never see the same incident twice is a CloudWatch alarm on the metric that would have warned you. For Amazon ElastiCache, the relevant metrics live under AWS/elasticache namespace or under custom metrics published by your Lambda or ECS task. Set thresholds based on observed normal range plus one or two standard deviations, not on round-number guesses. CloudWatch anomaly-detection alarms remove the threshold-guessing problem entirely for metrics with regular seasonality.
Codify the fix in Terraform or CloudFormation
When you reach for the console to fix the same issue twice, the third occurrence should be solved in IaC, not in the console. Terraform's terraform import and CloudFormation's resource importer let you adopt the existing resource into state without recreating it. Lock the corrected attribute behind a variable so the next operator does not have to rediscover the value. Add a moved {} block or CloudFormation resource refactor to keep the diff clean.
Pitfalls to dodge
The most common pitfall when fixing this on Amazon ElastiCache is treating it as a one-off rather than as a recurring class of incident. The same misconfiguration tends to happen again after a deployment, a role rotation, or a region migration unless the fix is codified. Add a CloudFormation hook, Service Control Policy condition, or AWS Config rule that prevents the same misconfig from being introduced again. Documentation alone does not survive turnover.
Another common trap: confirming the fix on a single resource and assuming the fleet is healthy. Loop your check across every account, region, and IAM principal that could exhibit the same symptom. If you cannot enumerate the affected scope without a script, you do not yet understand the scope.
Resolve
- Reproduce the original symptom path. If it still surfaces in any account or region or IAM role, you have not fixed it.
- Watch for 24 to 48 hours. AWS metrics and policy systems can mask issues with cached health for 6 to 12 hours, especially CloudFront and Route 53.
- Run a smoke test under realistic load. Happy-path tests miss race conditions and IAM session-cache issues.
- Capture the new state in a runbook so the next person on call does not have to rediscover this. Push it to Confluence or your team wiki, not into Slack.
- If the fix involved a permission change, run IAM Access Analyzer one more time to confirm you did not open a separate hole while closing this one.
Safety, rollback, blast radius
- Test in a non-production account if your environment has Control Tower or AWS Organizations. The cost of one sandbox account is cheaper than one rollback meeting.
- Export the existing config before changing it. Most Amazon ElastiCache resources support describe + export to JSON via CLI - capture that to source control before you start.
- Know your rollback path. Some Amazon ElastiCache operations are one-way (region migration, account-level feature opt-in, KMS key deletion past pending window). Confirm reversibility on the AWS doc before you commit.
- Be aware of cross-service impact. IAM role changes ripple to every service trusting that role. KMS key changes break every workload depending on that key. VPC endpoint changes affect every VPC consumer of that endpoint.
- Maintenance window discipline: if the change touches DNS, certificate rotation, or anything that emits TLS handshakes, line up a window with stakeholder notification, not a heroic mid-day swap.
FAQ
aws elasticache describe-... first, then commit it before you change anything. A few operations are one-way (KMS key deletion past the pending window, region migration, account closure). Check the AWS doc for the specific API before you commit.aws CLI or SDK calls - those almost always still work.References
- docs.aws.amazon.com - official documentation for Amazon ElastiCache
- AWS re:Post (formerly forums) - community Q&A with AWS-staff-verified answers
- AWS Health Dashboard at health.aws.amazon.com
- AWS Service Quotas console and AWS Well-Architected Tool
Related fixes
Related guides worth a look while you sort this one out:
- RedisClusterDown on Amazon ElastiCache. what causes it and how to fix
- RedisOOMException on Amazon ElastiCache, what causes it and how to fix
- RedisReadOnly on Amazon ElastiCache, what causes it and how to fix
- APIGateway403Forbidden on Amazon API Gateway: what causes it and how to fix
- APIGateway502BadGateway on Amazon API Gateway, what causes it and how to fix
- APIGatewayTooManyRequests on Amazon API Gateway. what causes it and how to fix