RCL SSL DNS AutoRenew for Linux

V7.1.0

RCL SSL DNS AutoRenew runs as a Daemon in a Linux hosting machine. The daemon will run every seven (7) days to automatically renew and save SSL/TLS certificates from a user’s subscription in the RCL SSL Portal to the Linux hosting machine.

Before you can use RCL SSL DNS AutoRenew, you must have already created your certificate(s) in the RCL SSL Portal using the Azure DNS or Azure DNS SAN option. The certificate(s) that you would like to install must be specified in your configuration of RCL SSL DNS AutoRenew.

Automatically Renew SSL/TLS Certificates

You can use RCL SSL DNS AutoRenew to automatically renew SSL/TLS certificates created in the RCL SSL Portal using the the following creation options :

Installing RCL SSL DNS AutoRenew

If you have an older version of the RCL DNS AutoRenew installed in your hosting machine, you should completely delete it and install the new one.

Download and Extract the Daemon Files to the Linux Server

In this section, you will download the files from the RCL SSL Automatic Certificate Renewal GitHub Project Page in the Releases section; and extract it to your Linux Server in the /usr/sbin folder:

  • In your Linux server, navigate to the /usr/sbin folder
cd /usr/sbin
  • Run the command in the folder to download and extract the linux-x64 files:
wget -c https://github.com/rcl-ssl/rcl-ssl-automatic-renewal/releases/download/V7.1.0/dns-autorenew-linux-x64.tar.gz -O - | sudo tar -xz

or linux-arm files :

wget -c https://github.com/rcl-ssl/rcl-ssl-automatic-renewal/releases/download/V7.1.0/dns-autorenew-linux-arm.tar.gz -O - | sudo tar -xz

or linux-arm64 files :

wget -c https://github.com/rcl-ssl/rcl-ssl-automatic-renewal/releases/download/V7.1.0/dns-autorenew-linux-arm64.tar.gz -O - | sudo tar -xz

Configure the Daemon

Register an AAD Application

An Azure Active Directory (AAD) application must be registered to obtain permission to access a user’s Azure resources (DNS Zone).

Please refer to the following link to register an AAD application:

Set Access Control for the AAD Application

Access control must be set for the AAD application to access resources (DNS Zone) in a user’s Azure subscription. Please refer to the following link to set access control :

Get the AAD Application Credentials

To obtain the following credentials from the AAD application:

  • ClientId
  • ClientSecret
  • TenantId

follow the instructions in this link :

Get the SubscriptionId

Get the Subscription Id in the RCL SSL Portal.

install

  • Scroll down and copy the ‘Subscription Id’

install

Register the AAD Application’s Client Id in the RCL SSL Portal

The AAD Application must be associated with a user’s RCL SSL subscription. This is achieved by registering the AAD Application’s Client Id in the RCL SSL Portal.

To add the AAD Application’s Client Id to the portal, please follow the instructions in this link :

Add the Configuration variables

  • Navigate to the folder you downloaded and extracted the daemon files :
cd /usr/sbin/dns-autorenew-linux-x64

or for arm

cd /usr/sbin/dns-autorenew-linux-arm

or for arm64

cd /usr/sbin/dns-autorenew-linux-arm64
  • Use nano (or other text editor) to edit the appsettings.json file in the folder
sudo nano appsettings.json
  • Add the credentials for the AAD Application and SubscriptionId in the RCLSDK section :
    • ClientId
    • ClientSecret
    • TenantId
    • SubscriptionId
"RCLSDK": {
    "ApiBaseUrl": "https://rclapi.azure-api.net/v2",
    "SourceApplication": "RCL SSL DNS AutoRenew Linux",
    "ClientId": "23568fghjrtr3",
    "ClientSecret": "7466rggvvdggdff",
    "TenantId": "1103984664",
    "SubscriptionId": "890"
  }
  • In the CertificateBot section, set a folder path to save the SSL/TLS certificates. Recommended path : /etc/ssl/rcl

    • SaveCertificatePath
  • The IncludeCertificatesArray settings will allow for including specific certificates by its name (eg: “contoso.com” or “contoso.com, * .contoso.com” - for SAN) for the certificate(s) you want to save on the server. Multiple certificates must be separated by a semi-colon (;), eg. shopeneur.com;acme.com;contoso.com,*. contoso.com

    • IncludeCertificatesArray

Example

"CertificateBot": {
  "IncludeCertificatesArray": "shopeneur.com",
  "SaveCertificatePath": "/etc/ssl/rcl"
}

Example of a configured appsettings.json file

{
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft.Hosting.Lifetime": "Information"
    }
  },
  "RCLSDK": {
    "ApiBaseUrl": "https://rclapi.azure-api.net/v2",
    "SourceApplication": "RCL SSL DNS AutoRenew Linux",
    "ClientId": "23568fghjrtr3",
    "ClientSecret": "7466rggvvdggdff",
    "TenantId": "1103984664",
    "SubscriptionId": "890"
  },
"CertificateBot": {
  "IncludeCertificatesArray": "shopeneur.com",
  "SaveCertificatePath": "/etc/ssl/rcl"
  }
}
  • Save the updated appsettings.json file when you are done

  • Create the folder in the server and ensure it has read/write permissions so that the certificates can be saved to it.

sudo mkdir -m 777 /etc/ssl/rcl

Add the Linux Daemon

Create the Daemon

  • Navigate to the /etc/systemd/system folder
cd /etc/systemd/system
  • Create the daemon file
sudo touch dnsautorenew.service
  • Use nano (or other text editor) to edit the service file
sudo nano dnsautorenew.service
  • Add the following code to the file
[Unit]
Description=RCL SSL DNS AutoRenew

[Service]
Type=notify
WorkingDirectory=/usr/sbin/dns-autorenew-linux-x64
ExecStart=/usr/sbin/dns-autorenew-linux-x64/RCL.SSL.DNS.AutoRenew.Linux

[Install]
WantedBy=multi-user.target

If you installed the arm version, change the directory to the arm path /usr/sbin/dns-autorenew-linux-arm or /usr/sbin/dns-autorenew-linux-arm64 instead of /usr/sbin/dns-autorenew-linux-x64 in the ‘WorkingDirectory’ and ‘ExecStart’ settings

  • Save the file when you are done

Reload the Daemon

  • Reload the daemon anytime you make changes to the service file
sudo systemctl daemon-reload

Start the Daemon

  • Run the code to start the daemon
sudo systemctl start dnsautorenew

View the Status of the Daemon

  • Run the code to view the status of the daemon
sudo systemctl status dnsautorenew
  • You will see the status of the daemon. The most recent logs will also be displayed.

  • Ensure that there are no errors in the logs. If there are errors, the daemon is misconfigured and will not function

View the Detailed Logs

  • Run the command to view the daemon’s detailed logs
sudo journalctl -u dnsautorenew --no-pager
  • If the application is working correctly you should see messages similar to the one below :
RCL.SSL.DNS.AutoRenew.Linux.Worker[0] Found 1 certificate(s) to save locally.  Successfully saved : shopeneur.com,*.shopeneur.com.  Did not find any certificates to renew.

If you need to Stop the Daemon

  • Run the code if you need to stop the daemon (in case you need to update settings or fix errors).

When the daemon is stopped, CertificateBot will discontinue certificate renewals and installation in the server.

Note: You need to keep the daemon running to automatically renew certificates.

sudo systemctl stop dnsautorenew

Fixing Errors

If you encounter errors in the logs for the daemon, please stop the daemon. Ensure the ‘appsettings’ configuration is correct for the AAD Application credentials and the certificate save path settings.

The folder to save the certificate must have read/write access.

Reload and restart the daemon after you make changes and check if the errors were resolved.

Updating the Daemon

If you need to update the service to include other certificates, follow these steps:

  • Stop the daemon
  • Change the appsettings.json file to include additional certificates
  • Re-load the daemon
  • Re-start the daemon

Reset the Daemon

If you need to reset the service because of a error or corrupted certificate renewal, follow these steps :

  • Stop the daemon
  • Delete all certificates and their folders in the directory in which certificates are saved
  • Re-load the daemon
  • Re-start the daemon

Testing Certificate Renewal

Force Certificate Expiration

In order to test certificate renewal, you must first force certificate expiration in the RCL SSL Portal.

  • In the RCL SSL Portal, click on the SSL/TLS Certificate > Certificates List link in the side menu

  • In the certificates list, click the Manage > Force Expiry link

  • In the Force Expiry page, click the Force Expiry button

  • The certificate will be forced to expire in the next 14 days

Force Expiry

Testing Renewal

  • Re-start the daemon to trigger the certificate renewal
sudo systemctl restart dnsautorenew
  • Run the command to view the daemon’s detailed logs
sudo journalctl -u dnsautorenew --no-pager
  • Check the logs to ensure the certificate is scheduled for renewal.
Found 1 certificate(s) to process locally.  Found 1 certificate(s) to renew.  Scheduling shopeneur.com for renewal. 
  • After about 15 mins, re-start the services to save the certificate to the local machine
sudo systemctl restart dnsautorenew
  • Run the command to view the daemon’s detailed logs
sudo journalctl -u dnsautorenew --no-pager
  • Check the logs to ensure the certificate is scheduled for renewal.
Successfully saved : shopeneur.com in local machine.

  • Check that the certificate files are stored in the folder that you specified. Review the section below to learn how the daemon saves certificate files

Example

 cd /etc/ssl/rcl
 ls
  • Once this test passes, the daemon will run every seven days to automatically renew certificates and save the certificate files to a folder you specify

Certificate Files

The SSL/TLS certificate files will be stored at the path you specified in the appsettings.json configuration file. In this example, we used the path /etc/ssl/rcl to store the certificate files.

At this path, a folder is generated by the service based on the certificate name. All the files for the certificate will be stored in this folder.

For each certificate, the following files are downloaded and saved on the hosting machine with the following file names:

  • certificate.pfx - The PFX certificate file
  • primaryCertificate.crt - The Primary Certificate file
  • fullChainCertificate.crt - The full chain certificate file
  • caBundle.crt - The Intermediate Certificates (CA Bundle) file
  • privateKey.key - The Certificate Private Key file

The files are saved in a folder generated by the daemon based on the certificate name following these conventions :

Type Example Certificate Name Example Folder Name
Apex Domain shopeneur.com shopeneur-com
Sub-domain store.shopeneur.com store-shopeneur-com
Wildcard domain *.shopeneur.com wcard-shopeneur-com
SAN HTTP Challenge shopeneur.com,www.shopeneur.com shopeneur-com-san-www
SAN DNS Challenge shopeneur.com,*.shopeneur.com shopeneur-com-san-wcard

Installing Certificates in Web Servers

After, you have installed the daemon and the renewed certificates have been downloaded to the specified folder. Please follow the links below to configure your web server to use the certificates files in the folder generated by the service :