etcd backup to Tencent Cloud COS

[TaoXieSZ]

Hi team, I am migrating etcd backup from s3 to COS, a s3 compatible service provided by Tencent Cloud. But I fail to test the backup:

rke2 etcd-snapshot save \
  --etcd-s3 \
  --etcd-s3-region "ap-beijing" \
  --etcd-s3-endpoint "test-bucket.cos.ap-beijing.myqcloud.com" \
  --etcd-s3-bucket test-bucket \
  --etcd-s3-folder "test-folder" \
  --etcd-s3-access-key "" \
  --etcd-s3-secret-key ""

Although the test-bucket exists, this command return error:

FATA[0000] see server log for details: bucket test-bucke does not exist

Here's another case:
I remove bucket name from the etcd-s3-endpoint:

rke2 etcd-snapshot save \
  --etcd-s3 \
  --etcd-s3-region "ap-beijing" \
  --etcd-s3-endpoint "cos.ap-beijing.myqcloud.com" \
  --etcd-s3-bucket test-bucket \
  --etcd-s3-folder "test-folder" \
  --etcd-s3-access-key "" \
  --etcd-s3-secret-key ""

But there is another error:

FATA[0000] see server log for details: failed to test for existence of bucket test-bucket: Access Denied.

Where can I get more details about how the request construct?
Thanks!

[huangyutongs]

I also studied it for a long time, and finally the following configuration can be successful

rke2 etcd-snapshot save \
  --name ManualSnapshot20250529 \
  --etcd-s3 \
  --etcd-s3-endpoint=k8s-etcd-backup-111111111.cos.na-siliconvalley.myqcloud.com \
  --etcd-s3-bucket=k8s-etcd-backup-111111111 \
  --etcd-s3-access-key=xxxxxxxxxxxxx \
  --etcd-s3-secret-key=xxxxxxxxxxxxx \
  --etcd-s3-folder uat

It looks like this on cos, make sure you have enough permissions.

https://k8s-etcd-backup-111111111.cos.na-siliconvalley.myqcloud.com/k8s-etcd-backup-111111111/uat/ManualSnapshot20250529-uat-k8s-master-1-111111111

I think it is because of a change made by Tencent Cloud that caused some incompatibility
https://cloud.tencent.com/document/product/436/96243