# SignatureDoesNotMatch with Ceph RGW S3 backend — path\_style not propagated to minio client

**URL:** <https://forum.pydio.com/t/signaturedoesnotmatch-with-ceph-rgw-s3-backend-path-style-not-propagated-to-minio-client/7932>\
**Category:** Pydio Cells\
**Tags:** s3\
**Created:** [March 27, 2026, 7:55am UTC](https://forum.pydio.com/t/signaturedoesnotmatch-with-ceph-rgw-s3-backend-path-style-not-propagated-to-minio-client/7932 "2026-03-27T07:55:50Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![SJoon99](https://yyz2.discourse-cdn.com/flex032/user_avatar/forum.pydio.com/sjoon99/32/3521_2.png) [@SJoon99](https://forum.pydio.com/u/SJoon99)\
**Post date:** [March 27, 2026, 7:55am UTC](https://forum.pydio.com/t/signaturedoesnotmatch-with-ceph-rgw-s3-backend-path-style-not-propagated-to-minio-client/7932/1 "2026-03-27T07:55:50Z")

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Describe your issue in detail

When using Ceph RGW as an S3-compatible backend, all datasync services fail with SignatureDoesNotMatch errors. The root cause is that path\_style (set during datasource bootstrap in discovery/install/lib/datasource.go) is never propagated to the  
MinIO client configuration.

Data flow of the bug:

1. During install, datasource.go correctly sets StorageConfiguration[“path\_style”] = “true” for custom S3 endpoints
2. FactorizeMinioServers() in common/config/datasources.go converts DataSource → MinioConfig, but only copies signatureVersion into GatewayConfiguration — path\_style and force\_path\_style are silently dropped
3. MinioConfig.ClientConfig() reads GatewayConfiguration[“path\_style”] to set BucketLookupPath — since it’s missing, it defaults to virtual-host style
4. Ceph RGW only supports path-style URLs ([http://endpoint/bucket/key](http://endpoint/bucket/key)), so virtual-host requests ([http://bucket.endpoint/key](http://bucket.endpoint/key)) produce a signature mismatch

Result: Every datasync service fails at S3 connection with SignatureDoesNotMatch, even though credentials are correct.

* * *

What version of Cells are you using?

v5-dev

* * *

What is the server OS? Database name/version?

- Server OS: Kubernetes (Linux)
- Database: MariaDB (config DB), MongoDB (document store), etcd (distributed config)
- S3 backend: Ceph RGW (S3-compatible, path-style only)

(This is a server-side issue, not browser-related)

* * *

What steps have you taken to resolve this issue already?

1. Traced SignatureDoesNotMatch errors through datasync logs to the minio client initialization
2. Identified that FactorizeMinioServers() drops path\_style when converting StorageConfiguration → GatewayConfiguration
3. Fixed common/config/datasources.go: added propagation of path\_style and force\_path\_style to GatewayConfiguration in all three S3 datasource conversion cases
4. Verified fix via etcd inspection: GatewayConfiguration.path\_style: “true” now present after bootstrap
5. Confirmed all datasync services connect successfully after fix
6. Submitted a PR with unit tests: [fix(s3): add path-style support to fix Ceph RGW S3 compatibility by SJoon99 · Pull Request #874 · pydio/cells · GitHub](https://github.com/pydio/cells/pull/874)

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<div class="post-metadata">

**Author:** ![c12simple](https://yyz2.discourse-cdn.com/flex032/user_avatar/forum.pydio.com/c12simple/32/90_2.png) [@c12simple](https://forum.pydio.com/u/c12simple)\
**Post date:** [April 3, 2026, 10:40am UTC](https://forum.pydio.com/t/signaturedoesnotmatch-with-ceph-rgw-s3-backend-path-style-not-propagated-to-minio-client/7932/2 "2026-04-03T10:40:13Z")

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Hi @SJoon99

I have a question on your PR, [fix(s3): add path-style support to fix Ceph RGW S3 compatibility by SJoon99 · Pull Request #874 · pydio/cells · GitHub](https://github.com/pydio/cells/pull/874)  
Could you please take a look

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<div class="post-metadata">

**Author:** ![system](https://canada1.discourse-cdn.com/flex032/uploads/pydio/original/2X/6/61f19fa52ec15fd4250db51aea351adba0e831fd.png) [@system](https://forum.pydio.com/u/system)\
**Post date:** [June 2, 2026, 10:40am UTC](https://forum.pydio.com/t/signaturedoesnotmatch-with-ceph-rgw-s3-backend-path-style-not-propagated-to-minio-client/7932/3 "2026-06-02T10:40:19Z")

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Closed on June 2, 2026, 10:40am UTC

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