Vendor Ports & Config
FlexLM and RLM license managers use two ports: a license port that clients connect to and a vendor daemon port that the ISV's vendor daemon listens on. By default, the vendor daemon port is dynamic and can change on every license server restart. That is fine on a LAN, but it breaks as soon as you put a firewall or a Rescale license proxy in between. This page explains how to pin the vendor port in your license file so your jobs on Rescale keep working across license server restarts.
Why the vendor port needs to be fixed
When a Rescale job checks out a license, it connects to the license port first, and lmgrd (FlexLM) or rlm (RLM) hands the client off to the vendor daemon on a second port. If that second port is dynamic, your firewall cannot allowlist it, the CLP cannot forward to it, and the checkout fails the first time the license server restarts. Pinning the vendor port makes it predictable and long-lived. Once it is fixed, you only need to open one license port and one vendor port on the firewall.
Shut down the on-premises license server or license manager before you change the vendor port, and confirm no Rescale or on-prem jobs are holding seats. Editing the license file while clients are connected can orphan checkouts and, for some ISVs, require a license rehost.
Choosing a vendor port
Pick a port that is easy to remember and is not already in use on your network. Rescale recommends round numbers like 27000 or 28000. Whatever you choose, the port must:
- Be open on your firewall and gateway between the Rescale license proxy and the license server.
- Not collide with another application. Common port conflicts include FlexLM's default 27000 range and web services on 8080 or 8443.
- Be used consistently across every license file on the server. If a host serves multiple license files, fix the vendor port in all of them, otherwise the license manager will fail to start with a port mismatch error.
Fixing the vendor port in a FlexLM license file
FlexLM is used by Ansys, Siemens STAR-CCM+, Dassault Abaqus, and COMSOL, among others. Open the license file as an administrator (right-click the file and Run as administrator on Windows, or open it with sudo or vim on Linux and macOS). A file without a fixed vendor port looks like this:
SERVER hostname xxxxxxxxxx 1055
VENDOR ansyslmd
Add PORT=<your-vendor-port> to the end of the VENDOR line. For Ansys with a vendor port of 28000:
SERVER hostname xxxxxxxxxx 1055
VENDOR ansyslmd PORT=28000
The same pattern applies to the other FlexLM-managed titles. Some baseline license port and vendor daemon pairings:
Fixing the vendor port in an RLM license file
RLM is used by Converge and MixIT, among others. The file structure is similar, but the vendor line starts with ISV instead of VENDOR. A file without a fixed port:
HOST hostname xxxxxxxxxx 2765
ISV csci
Add PORT=<your-vendor-port> to the ISV line. For Converge with a vendor port of 2760:
HOST hostname xxxxxxxxxx 2765
ISV csci PORT=2760
Verifying the port is pinned
After you save the file, restart the license server or license manager and confirm that the daemon came up on the port you set. The quickest check is the license log.
For FlexLM, look in a log like ansyslmd.log or cdlmd.log for lines similar to:
(lmgrd) FlexNet Licensing started on <hostname>
(lmgrd) lmgrd tcp-port <license server port>
(lmgrd) Started <vendor daemon> (pid <pid>)
(lmgrd) <vendor daemon> using TCP-port <vendor port>
For RLM, look for:
(rlm) License server started on <hostname>
(rlm) Using TCP/IP port <license server port>
(rlm) Starting ISV server <vendor daemon> on port <vendor port>
If the reported vendor port matches the one you set in the license file, the pin is live. If it does not, the license manager ignored the edit. The most common causes are editing the wrong copy of the license file, leaving out the PORT= token (case-sensitive on some versions), or forgetting to restart the daemon.
For LSTC-managed titles like LS-DYNA the vendor port is not used and you can skip this entire workflow. The license port alone is enough for the CLP.
What to do next
Once your vendor port is fixed in every license file on the server and the restart verifies the new port is live, open outbound rules on your firewall for both the license port and the vendor port, then continue with the CLP Overview to connect Rescale to the server.
Related
- CLP Overview for choosing IP forwarding or SSH tunnel mode once the vendor port is pinned.
- License Server Setup for the full prerequisites checklist on the server side.