> ## Documentation Index
> Fetch the complete documentation index at: https://gcore-doc-1894.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.
# Ignore the set cookie or query string parameters when caching content on CDN servers
The **Ignore query string** and **Ignore Set-Cookie** options control how query parameters and `Set-Cookie` response headers affect CDN caching. Both are available in the **Cache** section of CDN resource settings.
## Query string setting
The **Ignore query string** option determines how the CDN caches URLs that have query parameters. Query parameters are optional key-value pairs separated by `=` and joined by `&`, appearing at the end of a URL after a `?`:
```
http://cdn.example.com/photo.jpeg?id=6&color=blue
```
When disabled, the full query string is included in the cache key, so URLs with different query parameter values are cached as separate objects.
To enable it in the [Gcore Customer Portal](https://portal.gcore.com):
1. In the left sidebar, select **CDN**, then click the CDN resource to configure.
2. In the sidebar, under **Cache**, click **Query string**.
3. Enable the **Ignore query string** toggle.
Enabling or changing this option may invalidate cached content for URLs with query strings. CDN servers will request those files from the origin again, which can increase origin load.
4. Click **Save changes**.
The enabled option has three modes:
| Mode | Parameters in the list | Other parameters |
| ----------------- | ---------------------- | --------------------- |
| Ignore all | — | Ignored |
| Ignore all except | Included in cache key | Ignored |
| Ignore only | Ignored | Included in cache key |
* **Ignore all** (default). Files with different query parameters are cached as a single object, regardless of parameter values.
The following URLs are cached as a single object because all parameters are ignored:
```
http://cdn.example.com/photo.jpeg?id=6&color=blue
http://cdn.example.com/photo.jpeg?id=1&color=blue
```
* **Ignore all except**. Files with the specified query parameters are cached as separate objects; files with other parameters are cached as a single object.
Enter each parameter name on a separate line in the text field that appears.
With `id` in the text field: the following URLs are cached as separate objects because the `id` values differ, and the `color` parameter is ignored:
```
http://cdn.example.com/photo.jpeg?id=6&color=blue
http://cdn.example.com/photo.jpeg?id=1&color=blue
```
With `color` in the text field: the following URLs are cached as a single object because the `color` values are the same, and the `id` parameter is ignored:
```
http://cdn.example.com/photo.jpeg?id=6&color=blue
http://cdn.example.com/photo.jpeg?id=1&color=blue
```
* **Ignore only**. Files with the specified query parameters are cached as a single object; files with other parameters are cached as separate objects.
Enter each parameter name on a separate line in the text field that appears.
With `id` in the text field: the following URLs are cached as a single object because the `id` values are ignored, and the `color` values are the same:
```
http://cdn.example.com/photo.jpeg?id=6&color=blue
http://cdn.example.com/photo.jpeg?id=1&color=blue
```
With `color` in the text field: the following URLs are cached as separate objects because the `color` values are ignored, and the `id` values differ:
```
http://cdn.example.com/photo.jpeg?id=6&color=blue
http://cdn.example.com/photo.jpeg?id=1&color=blue
```
## Set-Cookie setting
By default, the CDN caches files with different `Set-Cookie` header values as separate objects. This means multiple cached copies of the same content can accumulate for different cookie values, reducing the cache hit ratio.
The **Ignore Set-Cookie** option changes this behavior: files are cached as a single object regardless of the `Set-Cookie` header value. Gcore recommends enabling this option for the best cache hit ratio.
To enable it, open the CDN resource settings (same page as the **Query string** option), enable the **Ignore Set-Cookie** toggle in the **Cache** section, then click **Save changes**.
