Blank screen on web based SSH console and terminal SSH

Question

Hello,

I recently took over management of a complex web project and one component is an AWS Lightsail instance. When I attempt to SSH to this instance it displays a "connecting" splash and then the content of the window is just black (see screenshot) - there's no prompt. I get the same thing when trying to SSH from my Mac's terminal. Is there anything I can try here apart from restarting?

EDIT: when I went back to check the web based console after a few minutes I received the timeout message seen in the second screenshot.

![Black Screen](/media/postImages/original/IMoJXR5uZDRACuPGpOI45wPQ)
![Timeout Screen](/media/postImages/original/IMi8EEfki5S8WGXWHD6TWtAQ)

re:Post Agent · Answer

The issue you're experiencing with the black screen on the web-based SSH console and the connection timeout in the terminal is a common problem with Lightsail instances. There are several potential causes and solutions you can try:

1. Instance Resource Usage: High CPU or memory usage can impact SSH responsiveness. Check your instance's resource metrics in the Lightsail console to see if there are any spikes or consistent high usage.

2. Firewall Settings: Verify that port 22 (for SSH) is open in your instance's firewall settings. Sometimes, these settings can change unexpectedly.

3. OS-level Firewall: The issue might be caused by a firewall on the Lightsail OS side. If you can access the instance, you could try running a script to disable the firewall and reset iptables:

sudo ufw disable
   sudo iptables -F
   sudo mv /etc/hosts.deny /etc/hosts.deny_backup
   sudo touch /etc/hosts.deny
   sudo systemctl enable sshd
   sudo systemctl restart sshd

4. Reboot the Instance: If you haven't already, try rebooting the instance from the Lightsail console. This is the least disruptive solution and maintains the same public IP.

5. Stop and Start the Instance: If a reboot doesn't work, try stopping and starting the instance. Note that this will change your public IP address unless you're using a static IP.

6. Instance Size: If you're consistently experiencing high resource usage, you might need to upgrade to a larger Lightsail plan.

7. Data Recovery: If you continue to have issues, consider creating a snapshot of your instance's root volume. This will allow you to recover your data and potentially attach it to a new, functioning instance.

If these steps don't resolve the issue, it may be worth contacting AWS Lightsail support for further assistance, as there could be underlying issues with the instance or the host system that aren't visible to you as a user.  
**Sources**  
[Lightsail SSH connect timing out | AWS re:Post](https://repost.aws/questions/QU9qGcOM9jRUm-8kiyTZHcXg/lightsail-ssh-connect-timing-out)  
[Lightsail SSH - Connection (Request)  Port 22: Connection timed out Issue . | AWS re:Post](https://repost.aws/questions/QUi9EYxRMESEOJFdlsN9Zlbg/lightsail-ssh-connection-request-port-22-connection-timed-out-issue)

Blank screen on web based SSH console and terminal SSH

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