License Proxy - IP Forwarding

A step-by-step guide for Rescale customers to setup a license proxy using IP forwarding mode on Rescale admin page

IP forwarding mode is a method that involves relocation of address and/or port numbers of a packet and sending it to a new destination. IP forwarding method is quick and easy to set up. It is a self service solution when configured requires no on-going maintenance. This is the simplest configuration that allows you to run batch jobs and desktops using Rescale to access your on-premise licenses.

  • The user should have an account on Rescale
  • The user should be a company administrator (in Rescale). To become a company administrator, please email a request to
  • The user should have admin privileges to the on-premises license server. This is the IT admin of the company who manages the on-premises license server
  • The user's computer should allow inbound ssh access on port 22
  • Your public IP address
  • Hostname for on-premises license server
  • List of software and associated license and vendor ports
  • Ensure that vendor ports are fixed in license files

This section lists the steps to be followed on your local on-premises workstation where the license server is hosted

Obtain Port Information

  • Obtain the port (license and the vendor) information from the license file

  • The port the license server listens on can be obtained from the license logs

  • For both FlexLM and RLM there are 2 processes that handle license access: the License Server (lmgrd or rlm) and the Vendor Daemon

  • For FlexLM, look at the part of the log when the license server was started. It will display information in the following format. You will need to obtain the ports from this part of the log:

00:00:00 (lmgrd) FlexNet Licensing (<license manager version>) started on <hostname>
00:00:00 (lmgrd) lmgrd tcp-port <license server port>
00:00:00 (lmgrd) Started <vendor daemon> (pid <pid>)
00:00:00 (lmgrd) <vendor daemon> using TCP-port <vendor port>

Similarly, the ports information for the Reprise License Manager (RLM) can be parsed from the license logs. The format of the logs will look something like this:

1/1 00:00 (rlm) License server started on <hostname>
1/1 00:00 (rlm) Using TCP/IP port <license server port>
1/1 00:00 (rlm) Starting ISV server <vendor daemon> on port <vendor port>

Update Vendor Ports

  • Before making changes to the vendor port(s), make sure you temporarily shutdown the license server and there are no running jobs

  • Open the license file in a text editor with admin privileges and edit the vendor port(s)

  • Each time the the server is restarted the vendor port(s) might change

Restart the License Server and Verify Changes

  • In order to apply the changes, the license server should be restarted

  • Look at the flexnet or Reprise License Manager (RLM) license log file and verify if the vendor port is correctly updated

This section lists the steps to setup license proxy using IP forwarding mode on Rescale Admin page. The license proxy setup on the Company Administration Page can be accessed at license proxy page

  • Navigate to the Rescale Administrator page from your accounts to start the setup of license proxy
  • Navigate to Integrations>>License Proxies
  • The page will look similar like the screenshot below:


  • Select Add New


  • Give an identifiable name for the license proxy

  • Select IP Forwarding mode as the license proxy mode

  • Do not make any changes to the "Enable High availability" option. The default value is No

  • Put in your public SSH keys for authorized connection to the license proxy server. This is not mandatory in case of IP forwarding mode. Only the users who want to have the access to the license proxy need to put in the SSH public key

  • If you are unsure on how to obtain public keys, please check out this page on SSH Key Setting up your SSH Key pair

  • Now, add the license port information Select a Unique Hostname for your license proxy. This is the hostname of the machine that hosts the license server. The hostname can be obtained from the license logs

  • Set the Destination IP. This is the IP address of the on-premise license server where you want to forward the traffic to. This can be same if you have multiple servers on the same network and different if you have multiple servers on multiple different network

  • Set the Local Port. This port is the port that the job refers to while checking out license. The proxy is listening on the local port Local port can be the same number as the Remote port. But, if you have two different license servers then you will have to give a different local port

  • The Remote Port is the port on the remote server that the local port forwards to

  • You will fill in the information for both License port and vendor port

  • The vendor and license port for each application needs to be on the proxy

  • For example, if you are using COMSOL Multiphysics in batch as well as COMSOL Multiphysics GUI in a Rescale Desktop, then you should have total 4 entries(2 license ports and 2 vendor ports) on the proxy page


  • Now, select the correct Software from the dropdown under software section on the proxy page

  • After that click on the Launch License Proxy button


  • Once you have clicked the launch proxy button you will see a screen with status like the one below:


  • After the proxy has been launched, you will see a network topology section at the bottom which will have the public IP of the Rescale license proxy that has to be whitelisted and adjust your firewall rules on your internet gateway to allow inbound from the Rescale license proxy to the on-premise license server


  • After, all of the above steps are configured properly, you should be able to see a screen like this:


  • Also, you should now be able to run jobs, and checkout licenses successfully

To test your connection and verify if the settings made were properly configured:

  1. Click on the radio button under actions options on the company license proxy page

Please note that the radio button only displays the status of the flexlm license servers. If you have a RLM license the radio button will not display any information

  1. Submit a dummy job by logging into your Rescale account
  • Create a new job by clicking the +New job button in the top left of the page. Select the Software you want in the software section and select Provide Existing License option as shown below:


  • In the appropriate field type in @ in our example case 27000@my-server then click Check availability the button. The license prompt provides customers immediate feedback for whether the license server address specified is reachable from the Rescale platform by clicking the blue ”Check Availability” button

Pro's :

  • It is the simplest setup to access on-premise licenses
  • It only needs the Rescale license proxy IP address to be whitelisted on the customer side
  • Does not require maintenance
  • It is a more robust solution because it doesn't rely on a tunnel being kept open

Con's :

  • It does not have any encryption