After updating to v2026.8.0-latest.1 +4 , my backups have started failing. These are the logs: log.txt.zip (22.1 KB) In particular, here’s the section that looks relevant: [2026-08-04 03:37:52] Uploading archive... [2026-08-04 03:37:52] EXCEPTION: uninitialized constant Aws::S3::TransferManager [20…

It looks like I’ve got an old version of aws-sdk-s3. $ bundle info aws-sdk-s3 * aws-sdk-s3 (1.177.0) Summary: AWS SDK for Ruby - Amazon S3 Homepage: https://github.com/aws/aws-sdk-ruby Source Code: https://github.com/aws/aws-sdk-ruby/tree/version-3/gems/aws-sdk-s3 Changelog: https://github.co…

The Discourse version you’re running includes an aws-sdk-s3 version that should provide Aws::S3::TransferManager. Are you using the official Discourse Docker installation? If you’re using the official Docker setup, was the container fully rebuilt as part of the upgrade?

Yes, I believe I’m using the official Discourse Docker installation. Is there a way for me to know for sure? It’s been a while since I’ve performed the installation. To update, I ran ./launcher rebuild app. I assume this means the container was fully rebuilt, but maybe I’m mistaken? A few more det…

One thing that may help narrow this down is checking which aws-sdk-s3 gem is actually being loaded inside the running container. The Discourse change which introduced Aws::S3::TransferManager also bumped aws-sdk-s3 from 1.182.0 to 1.227.0: FIX: Multipart S3 uplo…

One thought from this: temporary compatibility templates like this may be safer if they have some kind of self-expiring/guard condition, rather than continuing to override Discourse dependencies indefinitely. For example, with temporary source backports, i’m planning to use hooks in production that…

While I agree that failing loudly would have been nice, it was the case beforehand that I wanted the gems to not match the versions expected by Discourse, because the newer aws-sdk-s3 version sent headers that Backblaze did not support and I wanted the backups to work. I don’t know if there was a c…

Backup upload failure due to uninitialized TransferManager

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exodrifter (Ava Pek) September 14, 2026, 12:07am 2

I updated to v2026.9.0-latest +565, but I still ran into the same exact issue.

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Backup upload failure due to uninitialized TransferManager

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