Use tags - Cloud Backup - Alibaba Cloud Documentation Center

You can use tags to identify resources. You can use tags to categorize your ECS resources. This way, you can search and manage resources in a more efficient way. This topic describes how to use the tagging feature to back up ECS files.

Prerequisites

Authorization is completed in Resource Access Management (RAM) and an ECS file backup client is installed. For more information, see Prepare for data backup.

Background information

You can create different tags for different ECS instances. For example, if you manage teams or projects, you can create tags based on department or project and use these tags to categorize your instances. For example, you can create a tag named project:a for a project. This way, you can filter ECS instances based on the tag when you maintain ECS instances.

Usage notes

Each tag consists of a key-value pair.
A tag must be unique.
For example, the company:a tag is added to a backup vault. If you add the company:b tag to the backup vault, the company:a tag is replaced with the company:b tag.
Tags are not shared across regions. For example, tags that are created in the China (Hangzhou) region are invisible to the China (Shanghai) region.

Limits

When you create tags, take note of the following limits:

Item	Limit
The maximum length of a key	128 characters
The maximum length of a value	128 characters
The maximum number of custom tags that you can add to a resource	20
The key of a tag	The key cannot start with `aliyun` or `acs:`. The key cannot contain `http://` or `https://` . The key cannot be an empty string.
The value of a tag	A tag value cannot contain `http://` or `https://`.

Create tags

Log on to the Cloud Backup console.
In the left-side navigation pane, choose Backup > ECS File Backup.
In the top navigation bar, select a region.
On the ECS File Backup page, click Old Version.
In the Tags column, click the icon next to the name or ID of the ECS instance for which you want to create tags.
In the dialog box that appears, click Edit.
In the Key and Value fields, enter the key-value pair of a tag and click Save.
If you want to create more than one tag, click Add a row to specify the key-value pair of a new tag.

Search for resources by tag

On the right side of the ECS Instances tab, select Client Tags from the drop-down list and enter the tag information in the search box. Then, click the Search icon.

You can search for a resource by using a key, as shown in the following example:
```
aaa
```
You can search for a resource by using a key-value pair, as shown in the following example:
```
aaa:bbb
```
You can search for a resource by using multiple key-value pairs, as shown in the following example:
```
aaa:bbb,ccc:ddd
```