Hi, your PostgreSQL backup was successful (pg_dumpall completed, compression completed), but the compressed file size is 5.22 GB, which exceeds the 5 GB limit for a single S3 upload. Therefore, the upload step returned an HTTP 400 error.
This is a platform-side limitation. We will submit an internal ticket to fix this (by switching to multipart upload for large backup files).
Regarding your question about cold/hot backups: PostgreSQL uses online backup (hot backup). The service will not experience downtime during the backup process and normal usage will not be affected.
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