By using AWS re:Post, you agree to the Terms of Use
All Questions
Sort by most recent

Browse through the questions and answers listed below or filter and sort to narrow down your results.

Lost connection to MySQL server when scaling RDS Aurora Cluster

Hello, we're having some difficulty with our primary AWS Aurora Clusters and the various webservers that connect to them. Whenever a scaling operation occurs - both scaling up and scaling down - a large number of connections to the database are rejected ( 2,000+ ). We have noted the following errors from the RDS event log and our webservers: > The DB cluster failed to scale from 64 capacity units to 32 capacity units for this reason: A scaling point wasn’t found. > OperationalError: (2013, "Lost connection to MySQL server at 'reading initial communication packet', system error: 0") We have attempted to debug this problem with the following steps, but nothing has helped us to resolve it so far: * Reviewed MySQL error logs in Cloudwatch ( these only provided the server-level errors, nothing from RDS specifically ) * Turned off general MySQL logging * Ensured Apache / MySQL connection timeouts did not exceed the RDS Autoscaling Timeout * Verified all VPC, IGW, Route Table, and subnet settings associated with the instances connecting to the database. Below is some information regarding the cluster. > **Cluster Version**: > * Aurora MySQL (compatible with MySQL > > **Capacity Settings:** > * Minimum ACUs 16 - 32 GiB RAM > * Maximum ACUs 64 - 122 GiB RAM > > **Additional Scaling Configuration:** > * Autoscaling timeout and action: 00:05:00 > * Do this: Roll back the capacity change **Any advice or insight into possible avenues of troubleshooting or debugging would be highly appreciated at this point.**
asked 6 hours ago