# Troubleshoot SSH Connection

## Introduction

This guide is designed to help you troubleshoot and restore SSH access to your Validator node when it was previously working but is now unreachable.

{% content-ref url="/pages/pak1gd9we9flqJekCoMf" %}
[How to SSH into VPS](/run-a-node/references/ssh-remote-access/how-to-ssh-into-vps.md)
{% endcontent-ref %}

## Common Steps

✅ Verify the **username** for the VPS you're connecting to 

* e.g.) `nodeadmin`

✅ Check your **SSH key pair file names**

* Private key must match the server's authorized key.

✅ Confirm correct **permissions** 

* private key should be read-only:  `chmod 400`

✅ Ensure the **public key exists** on the server in the correct location

✅ Confirm the **private key file exists locally**

* Is it correctly referenced by your SSH command.

***

## :house: Local IP address

Many ISPs assign **dynamic IP addresses** to customer routers.

A change in your IP may cause your cloud provider’s firewall to block your SSH attempts.

### :adhesive\_bandage:Symptoms:

| Your SSH terminal or remote connection application sits idle and eventually shows `Connection timed out` messages. |
| ------------------------------------------------------------------------------------------------------------------ |
| Terminal or remote terminal application will how a blank screen only                                               |
| No password or key prompts appear                                                                                  |
| Not entering the SSH connection string and attempting to run commands locally instead of through your SSH tunnel.  |

💡 Example:

```bash
ssh -i ~/.ssh/my_identity_file nodeadmin@13.13.13.13
ssh: connect to host 13.13.13.13 port 22: Operation timed out
```

***

## 🔧 How to Fix It

{% stepper %}
{% step %}

### Determine your new IP address

Open your web browser and navigate to:

### [<kbd>www.whatismyip.com</kbd>](http://www.whatismyip.com/)&#x20;

{% endstep %}

{% step %}

### Record New IP Address

Copy your **current public IPv4 address**
{% endstep %}

{% step %}

### Cloud Provider Console

Go to your **cloud provider's web console.**
{% endstep %}

{% step %}

### Update Firewall Rules

Update your **firewall or security group rules** to allow SSH access **from your new IP**

* **AWS**: Update the Security Group
* **DigitalOcean**: Update Firewall settings
* **Hetzner**: Follow DigitalOcean-style firewall update workflow

{% hint style="warning" %}
Refer to the [Cloud Provider Specific Guides](/run-a-node/validator-node-guides/build-your-node/cloud-provider-specific.md).
{% endhint %}
{% endstep %}
{% endstepper %}

Try connecting again after updating the rules.

***

## 🔐 SSH Key Issues

### 📍 Local Key Issues

Ensure the private key file:

* Still exists in the expected location
* Has not been renamed or moved
* Is intact and not corrupted
* Has the proper permissions

{% hint style="info" %}
📌 Tip:&#x20;

If in doubt, restore your key from a **known-good** backup.
{% endhint %}

**Important:** Once resolved, **create a backup** of your SSH keys if you haven’t already.

***

## 📡 Remote Key Issues (Accessing via Console)

If you can still access your VPS through your **cloud provider's web console**:

{% stepper %}
{% step %}

### Log into the Web Terminal

{% endstep %}

{% step %}

### Navigate to the `.ssh` Directory

```bash
cd ~/.ssh
ls -l
```

{% endstep %}

{% step %}

### Verify Public Key

Check for the authorized public key file&#x20;

&#x20;`authorized_keys` or `.pub` file.

If the key is missing or incorrect:

Check alternate directories:

```bash
ls -l /root/.ssh/
ls -l /home/ubuntu/.ssh/
ls -l /home/admin/.ssh/
```

{% endstep %}

{% step %}

### Identify `_backup`

If you find your key with a `_backup` attached to the name of the file, issue the following command and check again:

Enable root SSH temporarily:

```bash
sudo nodectl enable_root_ssh
```

{% endstep %}

{% step %}

### Copy SSH Key Back Over

Copy the key into your nodeadmin’s `.ssh` directory :

```bash
sudo cp /root/.ssh/mypublickey.pub /home/nodeadmin/.ssh/mypublickey.pub
```

Change ownership

```
sudo chown nodeadmin:nodeadmin /home/nodeadmin/.ssh/mypublickey.pub
```

{% endstep %}

{% step %}

### Disable Root Access Again

```
sudo nodectl disable_root_ssh
```

{% endstep %}
{% endstepper %}

Re-Attempt to create an SSH connection to your node.

***

## 📡 Cloud Provider Outage

* Visit your cloud provider’s **main dashboard**
* Look for service alerts
* If the console is also unreachable, check external outage reports&#x20;
  * Google
  * Twitter
  * [Downdetector](https://downdetector.com)

***

## 🖥️ VPS-Specific Issue

* From the cloud console, check the **status of your VPS instance**
* Ensure it’s running and not reporting hardware or OS-level errors

***

## 🌍 Local Internet Outage

* If you cannot connect to any external site or service, confirm your own network is online
* Restart your router/modem if necessary and try again later


---

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