User Vortico encountered an error “Unsupported value for canned acl ‘public-read’” when uploading images, despite having “enable s3 uploads” disabled in settings. They initially believed DISCOURSE_USE_S3: true in app.yml was only for backups, but RGJ clarified it controls uploads. After setting DISCOURSE_USE_S3 to false and rebuilding, the error persisted Vortico. An admin warning indicated S3 was still configured for uploads, even though it was unintended. Simsnet suggested commenting out the line instead of setting it to false. Vortico confirmed that commenting out all DISCOURSE_S3_* settings resolved the upload issue, but feared this would break S3 backups. In post 8, they asked whether it’s possible to configure Discourse to use S3 for backups while keeping uploads local — sharing their current commented-out S3 config for reference. The core issue appears to be that DISCOURSE_USE_S3 governs both uploads and backups, and there’s no documented way to separate the two functions in Discourse’s current configuration.
When I try to upload an image to a post in my forum, it fails to upload the image and I get an error message
Unsupported value for canned acl ‘public-read’
This looks like an S3 error, but I have “enable s3 uploads” disabled in the file settings. I don’t want to upload images to S3. I have DISCOURSE_USE_S3 set to true in app.yml, but this is for daily S3 backups.
Does anyone see anything wrong with my configuration? Thanks!
But it’s not. DISCOURSE_USE_S3 is for uploads.
I set it to false and rebuilt the container, but it didn’t seem to fix the error or upload failure. I re-enabled it, but I’ll try it again.
DISCOURSE_USE_S3 is now false, and the container is rebuild, but it’s still showing the original error message.
I noticed this message appears in my admin dashboard.
The server is configured to upload files to S3, but there is no S3 CDN configured. This can lead to expensive S3 costs and slower site performance. See “Using Object Storage for Uploads” to learn more.
But I don’t want to upload files to S3. How do I disable it? Both DISCOURSE_USE_S3 and “enable s3 uploads” are disabled.
Did you comment out the line in app.yml?
No, I set it to false. I’ll try commenting it out.
I’ve commented out DISCOURSE_USE_S3 and all DISCOURSE_S3_* settings, and I can now upload images. However, I believe this will break the daily backups to S3. I suppose I can try commenting out just DISCOURSE_USE_S3, waiting 24 hours, and checking whether both uploads without S3 and backups with S3 still work.
Looks like I must omit all DISCOURSE_S3_* settings to make uploads work. Is there a way to allow both S3 backups and non-S3 uploads to work in Discourse?
Here are my relevant app.yml variables for reference. Currently everything is commented out.
# DISCOURSE_USE_S3: false
# DISCOURSE_S3_REGION: "us-west-000"
# DISCOURSE_S3_INSTALL_CORS_RULE: false
# DISCOURSE_S3_CONFIGURE_TOMBSTONE_POLICY: false
# DISCOURSE_S3_ENDPOINT: https://s3.us-west-000.backblazeb2.com
# DISCOURSE_S3_ACCESS_KEY_ID: <censored>
# DISCOURSE_S3_SECRET_ACCESS_KEY: <censored>
# DISCOURSE_S3_BUCKET: community-backup
# DISCOURSE_S3_BACKUP_BUCKET: community-backup
# DISCOURSE_BACKUP_LOCATION: s3