FAQ¶
Below you will find answers to the most frequently asked questions about Cloud4You Object Storage S3.
Which endpoint should I use?¶
For most use cases, use:
Region:
What information is required to connect?¶
You need:
Example:
Endpoint: https://s3.cloud4you.pl
Region: eu-pl-1
Access Key: <received Access Key>
Secret Key: <received Secret Key>
Is Cloud4You Object Storage compatible with Amazon S3?¶
The service provides an API compatible with Amazon S3.
This means you can use many applications, libraries, and tools that support a custom S3 endpoint.
Examples:
- AWS CLI,
- rclone,
- backup applications,
- graphical clients,
- AWS SDK libraries,
- boto3,
- custom applications.
Do I need an AWS account?¶
No.
An Amazon Web Services account is not required to use Cloud4You Object Storage S3.
You receive separate Cloud4You credentials:
Are the Access Key and Secret Key a username and password?¶
As a simplification, you can think of them this way:
Technically, they are credentials used to sign S3 API requests.
Secret Key
Treat the Secret Key like a password and do not share it with unauthorized persons.
Where can I find the username?¶
Most S3 clients do not require a separate username.
The connection uses:
What is a bucket?¶
A bucket is a container for objects.
Example:
It may contain objects such as:
Is a bucket a folder?¶
Not exactly.
A bucket is the main S3 container.
Inside a bucket, object keys can look like directories:
However, S3 does not have traditional directories in the same way as a local filesystem.
Can I create several buckets?¶
Yes, as long as you have not reached the bucket count limit assigned to your account.
The exact limit depends on the service parameters.
Does each bucket have a separate capacity limit?¶
Not always.
In a standard configuration, storage may be assigned to the user, and all of the user's buckets share the same quota.
Example:
Can I increase the quota?¶
If you need more storage, contact Cloud4You.
The change depends on the parameters of the purchased service.
Can I increase the number of buckets?¶
Yes, if the service allows this limit to be changed.
Contact Cloud4You and specify the required limit.
Can a bucket name contain uppercase letters?¶
We recommend using only:
- lowercase letters,
- numbers,
- hyphens.
Example:
Avoid:
Can a bucket have any name?¶
No.
The name must follow S3 naming rules.
The safest format is:
Does the bucket name have to be unique?¶
Yes, within the namespace required by the service.
If the selected name is already in use, bucket creation may fail.
In that case, choose a different name.
What does region eu-pl-1 mean?¶
It is the region used by Cloud4You Object Storage S3.
If the client or application requires a region, enter:
Can I leave the region empty?¶
Some applications allow this, but we recommend always specifying:
This reduces the risk of request-signing problems.
Do I have to use HTTPS?¶
Yes. HTTPS is the recommended and public connection method.
Use:
Do not use:
Can I disable SSL/TLS certificate verification?¶
We do not recommend it.
If an application reports a certificate error, check:
- the endpoint,
- system time,
- the CA certificate store,
- local firewall or proxy configuration.
Disabling TLS verification should only be treated as a temporary diagnostic test, not a production solution.
Can I open a bucket directly in a web browser?¶
Opening a bucket URL in a browser does not mean you will see its contents.
Buckets are private by default and require proper authentication.
A web browser does not automatically create signed S3 requests using your Access Key and Secret Key.
Why do I see AccessDenied in a browser?¶
This is usually the expected behavior for a private bucket.
Example:
means that an anonymous user does not have access to the data.
Use an S3 client to work with a private bucket.
Why do I see NoSuchBucket?¶
The most common causes are:
- a typo in the bucket name,
- the bucket does not exist,
- the application is using the wrong endpoint,
- an incorrect addressing method.
Check the bucket list:
Can I make a bucket public?¶
S3 technically supports access policies and public resources, but you should not do this unless there is a deliberate need.
Public access
Backups, archives, business documents, and other confidential data should remain private.
If you need public access to objects, make sure you understand the consequences and scope of the permissions being granted.
Can I share only one file?¶
Depending on the configuration and client capabilities, you can use temporary signed URLs for individual objects.
This allows you to share one specific object without publishing the entire bucket.
What is a presigned URL?¶
A presigned URL is a temporary URL that permits a specific operation on an object without giving the recipient the Access Key and Secret Key.
Example uses:
- temporary file download,
- temporary document sharing,
- application integration.
The validity period depends on the parameters used when the URL is created.
Does S3 have folders?¶
Not in the traditional sense.
A key such as:
may be displayed as:
but technically the entire string:
is the Object Key.
Can I upload large files?¶
Yes.
S3-compatible clients can use Multipart Upload.
AWS CLI handles multipart uploads automatically for large files.
Example:
aws \
--profile cloud4you \
--endpoint-url https://s3.cloud4you.pl \
s3 cp duzy-plik.tar.gz s3://firma-backup/
Can I resume an interrupted upload?¶
This depends on the client and the upload method being used.
Applications using Multipart Upload may provide retry or resume mechanisms.
AWS CLI automatically handles many aspects of large-file transfers.
What happens when I overwrite a file?¶
If versioning is disabled, new content uploaded under the same Object Key replaces the previous content.
If versioning is enabled, the older version may be retained.
Can an overwritten file be recovered?¶
If versioning was enabled on the bucket beforehand, an older version may still exist.
Check:
aws \
--profile cloud4you \
--endpoint-url https://s3.cloud4you.pl \
s3api list-object-versions \
--bucket firma-backup
If versioning was not enabled, the previous version may have been permanently replaced.
Can a deleted file be recovered?¶
If the bucket has versioning enabled, an earlier version may still exist in storage.
If versioning was disabled, a standard object deletion is permanent.
Is versioning a backup?¶
No.
Versioning is an additional protection mechanism against accidental changes and deletions.
It does not replace an independent backup.
Does versioning increase storage usage?¶
Yes.
Every retained object version consumes storage.
Example:
plik.zip - current version: 10 GB
plik.zip - old version: 10 GB
plik.zip - old version: 10 GB
Total: 30 GB
Why did storage usage not decrease after deleting a file?¶
One possible reason is that versioning is enabled.
A normal delete may create a Delete Marker while older versions remain in the bucket.
Check:
aws \
--profile cloud4you \
--endpoint-url https://s3.cloud4you.pl \
s3api list-object-versions \
--bucket firma-backup
Can I use AWS CLI?¶
Yes.
Use the Cloud4You endpoint with every command:
and the region:
Can I use rclone?¶
Yes.
Configure the S3 provider, endpoint:
and region:
Can I use Cyberduck or another graphical client?¶
Yes, if the client supports a custom S3 endpoint.
Use:
Can I use S3 with Veeam?¶
If the Veeam product and version you use support S3-compatible repositories with a custom endpoint, the service can be configured for use with it.
The detailed configuration depends on the specific Veeam product and version.
Can I use S3 in my own application?¶
Yes.
You can use libraries compatible with the Amazon S3 API.
Examples:
- Python boto3,
- AWS SDK for Java,
- AWS SDK for JavaScript,
- AWS SDK for .NET,
- AWS SDK for PHP.
Configure the SDK endpoint as:
and the region as:
Can I mount S3 as a disk?¶
You can use tools such as rclone mount, but remember that S3 is not a traditional filesystem.
We do not recommend this approach for:
- databases,
- virtual machine disks,
- applications requiring POSIX file locks,
- workloads requiring local-filesystem behavior.
Is S3 suitable for backups?¶
Yes.
Object Storage is commonly used as a backup repository.
The backup application must support S3-compatible storage.
Is S3 suitable for databases?¶
Not as a direct active filesystem for database files.
You can, however, store the following in S3:
- exports,
- dumps,
- backups,
- database archives.
Is S3 suitable for virtual machine disks?¶
Not as direct block storage for running virtual machines.
S3 is object storage, not block storage.
Can I synchronize an entire directory?¶
Yes.
AWS CLI:
aws \
--profile cloud4you \
--endpoint-url https://s3.cloud4you.pl \
s3 sync ./dane/ s3://firma-backup/dane/
rclone:
What is the difference between copy and sync?¶
In simplified terms:
copies new and changed data without automatically deleting extra files at the destination.
tries to make the destination match the source and may delete data.
Be careful with sync
Before using sync, test it with --dry-run if the client supports it.
Can I check used storage space?¶
Some clients can calculate the size of currently visible objects.
Example with rclone:
Remember that the result may not include every item that affects quota, such as older object versions.
Why does the application show a different amount of data than the quota?¶
Possible causes include:
- versioning,
- old object versions,
- Delete Markers,
- incomplete Multipart Uploads,
- differences in how size is calculated.
Can I change the Secret Key?¶
Yes.
The safest rotation procedure is:
- create new credentials,
- configure the application with them,
- test the connection,
- disable the old key.
What should I do if the Secret Key is exposed?¶
Treat it as compromised.
You should:
- stop using it,
- contact Cloud4You,
- obtain new credentials,
- update application configuration,
- remove or deactivate the old key.
Should I send the Secret Key to support?¶
No.
Never send the Secret Key in a support ticket
Cloud4You does not need your Secret Key for standard diagnostics.
Instead, provide:
- endpoint,
- region,
- application name,
- client version,
- bucket name,
- error message,
- exact time,
- Request ID.
What should I include in a support ticket when an error occurs?¶
Example of a good support request:
Endpoint: https://s3.cloud4you.pl
Region: eu-pl-1
Application: AWS CLI 2.x
Operation: ListBuckets
Bucket: firma-backup
Error: AccessDenied
Time of occurrence: 2026-08-27 14:30 CEST
Request ID: <if available>
The more precise the technical information, the faster the problem can be identified.