How to regenerate original self-signed certificates on NAS series storage

In this quick guide, we will cover creating a new pair of self-signed certificates on your NAS, discarding any other certificates installed on NAS. This is helpful in case the SSL menu in WebGUI gets stuck on Error 500 and you need to access it or even in situations when WebGUI becomes unresponsive due to various certificate errors.

Prerequisites:

• NAS series storage with SSH enabled
• Computer with connectivity to NAS and with SSH capability (virtually any modern PC even with just Windows on it)

Generating the certificates

1. Open a command prompt. To connect, use the following command with the address of your NAS and approve the connection if prompted.

   $ ssh root@192.168.1.33

2. Run following commands to restore the certificate repository to default (omit the first line to just generate new certificates). You will be prompted to enter information about the certificate. Defaults are fine enough, so just press enter until you reach the command prompt again.

   # find /etc/zyxel/cert -type f -delete
   # openssl req -newkey rsa:2048 -nodes -keyout /etc/zyxel/cert/key/default_key.cer -x509 -days 3650 -out /etc/zyxel/cert/default.cer

3. That's all! Feel free to exit the command prompt. You may also need to reboot the NAS for changes to take effect.

   # exit