# Use Labels

Labels are key-value maps associated with a resource, such as 
[Load Balancer]({{< ref "/product/networking/nlb/overview/" >}}), 
[Instance Pool]({{< ref "product/compute/instances/how-to/instance-pools/" >}}), 
et cetera. This allows you to attach additional meta information to an entity.

## Adding Labels

Your resources can be labeled using the web portal as well as the 
[CLI]({{< ref "/tools/command-line-interface/" >}})
command. Here is an example of adding `env=prod` label on Instance Pool creation:

```bash
exo compute instance-pool create web \
    --zone ch-gva-2 \
    --size 2 \
    --description "Web servers" \
    --instance-type "medium" \
    --ipv6 \
    --label env=prod \
    --template 4635f170-4a5a-4443-8b95-006bb755060e
```

Output:

```bash
 ✔ Creating Instance Pool "web"... 21s
┼──────────────────────┼──────────────────────────────────────┼
│ ID                   │ 376d45be-9afe-4c65-996a-da68d9ef618b │
│ Name                 │ web                                  │
│ Description          │ Web servers                          │
│ Instance Type        │ standard.medium                      │
│ Template             │ TEST                                 │
│ Zone                 │ ch-gva-2                             │
│ Anti-Affinity Groups │ n/a                                  │
│ Security Groups      │ n/a                                  │
│ Private Networks     │ n/a                                  │
│ Elastic IPs          │ n/a                                  │
│ IPv6                 │ true                                 │
│ SSH Key              │ -                                    │
│ Size                 │ 2                                    │
│ Disk Size            │ 50 GiB                               │
│ Instance Prefix      │ pool                                 │
│ State                │ running                              │
│ Labels               │ env:prod                             │
│ Instances            │ pool-376d4-lwafb                     │
│                      │ pool-376d4-mylpf                     │
┼──────────────────────┼──────────────────────────────────────┼
```

## Usage

> [!NOTE]
> On update, labels can't be appended or changed - the existing key-value map will be replaced with a new one.

## Limitations

- The label value should begin with a non-numeric character. It can contain only alphanumeric characters and the `*`, `+`, `!`, `-` (hyphen), `_` (underscore), and `?` symbols. The value is limited to 128 characters.