Use your own security certificate

Info

This procedure, combined with a proper Certificate Authority (internal or external), will resolve NET::ERR_CERT_AUTHORITY_INVALID errors.

By default, octoplant will automatically create a self-signed certificate and private key at runtime.

To use your own certificate instead of the one created by octoplant (recommended f.e. for OIDC or for the WebClient), follow this optional procedure. This guide is intended for IT departments or domain administrators.

Warning

After replacing the octoplant certificate with your own, you must update EVERY octoplant client computer. Otherwise, clients will not be able to connect.

If D:\certs\rootCA.crt is installed as a trusted root authority on every client, and the server name used by the client matches the Common Name, no further steps are needed.

If not, delete the knownhosts.txt file:

In the client archive of every client: \vdClientArchive\VD$A\Configuration\Local
In the server archive of the server: \vdServerArchive\VD$A\Configuration\Local

Basic steps

Create a root CA private key and public certificate. Import the certificate as a Trusted Root certificate on the server and all clients using this server. This root CA can be used for multiple servers.
For each server, create a private key and a certificate signing request (CSR).
Use the root CA's private key to sign the public server certificate.
Store the server's private key and signed certificate in the server archive.

Requirements

You need an environment with OpenSSL installed (recommended: OpenSSL 3.2.1 or later). To check your version, open a Command Shell and run:
```
openssl -v
```
You should see output similar to:
```
OpenSSL 3.5.2 5 Aug 2025 (Library: OpenSSL 3.5.2 5 Aug 2025)
```
Create a local folder for your certificates, e.g., D:\certs.

Create your own Root CA

This process has three steps:

Create a root key
Create and self-sign the root certificate
Distribute the certificate

Warning

The root CA key can sign any server certificate. Anyone with access to this key can create trusted certificates. Keep it safe and private.

Create a root CA key (rootCA.key):
```
openssl genrsa -aes128 -out D:\certs\rootCA.key 4096
```
You’ll be prompted for a passphrase, which you’ll need each time you sign a certificate. To create a key without a passphrase, remove the -aes128 option.

Create the root certificate (rootCA.crt):

openssl req -x509 -new -nodes -key D:\certs\rootCA.key -sha256 -days 1024 -out D:\certs\rootCA.crt

Distribute rootCA.crt to every client that will connect to the server.

Create a Server Certificate Signing Request

Create the server's certificate key (hostname.key):
```
openssl genrsa -out D:\certs\hostname.key 2048
```
This file is the server’s secret. Do not share or distribute this file, only the server should have access to it.
Create a signing request (hostname.csr):
```
openssl req -new -key D:\certs\hostname.key -out D:\certs\hostname.csr
```
Follow the interactive prompts. The Common Name must match the exact hostname clients use to connect. Do not set a password.

(Optional) Verify the CSR:

openssl req -in D:\certs\hostname.csr -noout -text

Sign the server certificate

Use the CSR, root CA key, and root certificate to create the signed server certificate (hostname.crt):

openssl x509 -req -in D:\certs\hostname.csr -CA D:\certs\rootCA.crt -CAkey D:\certs\rootCA.key -CAcreateserial -out D:\certs\hostname.crt -days 3650 -sha256

You’ll be prompted for the root CA key passphrase. The resulting hostname.crt and hostname.key are needed by the octoplant server.

Verify the certificate

Under Certificates, right-click on {server_name}.
Select Open.
Review the certificate information.
On the Details tab, select Subject Alternative Name to verify DNS and IP entries.
Select OK and exit the console.

Store the signed server certificate

Replace the following files in VD$A\Configuration\Local, located in the server archive:

ApiCertificate and CSCCertificate: with a copy of D:\certs\rootCA.crt
ApiPrivateKey and CSCPrivateKey: with copy of D:\certs\hostname.key

Do not use file extensions.

The certificate creation process is complete. Now you can:

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