# SSH 密钥对

SSH（安全外壳）密钥对用于身份验证和加密通信，由一个公网密钥和一个私网密钥组成。公网密钥可以用来加密只有私网密钥才能解密的消息。这一特性作为使用密钥对进行身份验证的方式。您的 SSH 密钥对包含多个公网密钥，可以放置在服务器上以安全访问。

## 支持的格式 <a href="#supported-formats" id="supported-formats"></a>

SSH 密钥通常存储在 \~/.ssh/ 目录中。

<table><thead><tr><th width="196">格式</th><th width="265">以...开头</th><th>最小长度</th></tr></thead><tbody><tr><td><strong>RSA</strong></td><td>ssh-rsa</td><td>2048 位</td></tr><tr><td><strong>ED25519</strong></td><td>ssh-ed25519</td><td>256 位</td></tr><tr><td><strong>ECDSA</strong></td><td>ecdsa-sha2-nistp</td><td>256 位</td></tr></tbody></table>

{% hint style="info" %} <mark style="color:blue;">**注意**</mark>

* <mark style="color:blue;">提供您的公网密钥。请小心不要使用您的私网密钥。</mark>
* <mark style="color:blue;">建议您使用</mark> <mark style="color:blue;">**RSA**</mark> <mark style="color:blue;">或</mark> <mark style="color:blue;">**ED25519**</mark> <mark style="color:blue;">密钥，因为它们具有良好的兼容性和安全性。</mark>
  {% endhint %}

## 示例 <a href="#example" id="example"></a>

这里我们以 RSA 格式为例。

### 公网密钥 <a href="#public-key" id="public-key"></a>

```
ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDx6VN...
```

### 私网密钥 <a href="#private-key" id="private-key"></a>

```
-----BEGIN RSA PRIVATE KEY-----
Proc-Type: 4,ENCRYPTED
DEK-Info: AES-256-CBC,5764636E65726F726974686D616E6F6E
...
-----END RSA PRIVATE KEY-----
```

## 限制 <a href="#limit" id="limit"></a>

您可以添加最多 5 个公网密钥以创建 SSH 密钥对。


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