# Create Replication Rules

Login as a system administrator user, click `NEW REPLICATION RULE` under `Administration->Replications` and fill in the necessary fields. You can choose different replication modes, [resource filters](#resource-filter) and [trigger modes](#trigger-mode) according to the different requirements. If there is no endpoint available in the list, follow the instructions in the [Creating replication endpoints](#creating-replication-endpoints) to create one. Click `SAVE` to create a replication rule.  

![browse project](../../img/create_rule.png)

#### Resource filter
Three resource filters are supported:
* **Name**: Filter resources according to the name.
* **Tag**: Filter resources according to the tag.
* **Resource**: Filter images according to the resource type.

The terms supported in the pattern used by name filter and tag filter are as follows:
* **\***: Matches any sequence of non-separator characters `/`.
* **\*\***: Matches any sequence of characters, including path separators `/`.
* **?**: Matches any single non-separator character `/`.
* **{alt1,...}**: Matches a sequence of characters if one of the comma-separated alternatives matches.

**Note:** `library` must be added if you want to replicate the official images of Docker Hub. For example, `library/hello-world` matches the official hello-world images.  

Pattern | String(Match or not)
---------- | -------
`library/*`      | `library/hello-world`(Y)<br> `library/my/hello-world`(N)
`library/**`     | `library/hello-world`(Y)<br> `library/my/hello-world`(Y)
`{library,goharbor}/**` | `library/hello-world`(Y)<br> `goharbor/harbor-core`(Y)<br> `google/hello-world`(N)
`1.?`      | `1.0`(Y)<br> `1.01`(N)

#### Trigger mode
* **Manual**: Replicate the resources manually when needed. **Note**: The deletion operations are not replicated. 
* **Scheduled**: Replicate the resources periodically. **Note**: The deletion operations are not replicated. 
* **Event Based**: When a new resource is pushed to the project, it is replicated to the remote registry immediately. Same to the deletion operation if the `Delete remote resources when locally deleted` checkbox is selected.