Using Ansys, COMSOL and Abaqus licenses on cloud GPUs

Running commercial solvers on cloud infrastructure requires both a compatible setup and permission under the applicable license. Before changing networking, confirm entitlement, identify the license system and validate the client configuration. The FlexNet examples below are conditional setup examples, not permission to move any license to any provider. Ask your license administrator or vendor to confirm the intended cloud, region, users and solver features.

What you need to know in 60 seconds

• Ansys and COMSOL deployments can use FlexNet: an lmgrd manager and vendor daemon handle license checkout. Abaqus may use FlexNet or Dassault Systèmes License Server (DSLS); confirm the configured system before following either setup.
• A FlexNet client may use a port@server value such as 1055@licenses.my-org.edu. DSLS uses its own client configuration.
• For a permitted FlexNet setup, have IT pin ports for lmgrd and the vendor daemon, then use an approved VPN or validated SSH tunnels. Some Ansys configurations also require Licensing Interconnect; a two-port recipe is not universal.
• Do not expose raw license-server ports to the public internet. Restrict access to the approved private or encrypted network path.

Decide your connectivity pattern

Pick one. Test it. Document it for your lab.

1. VPN to your org
   Use an IT-approved VPN and confirm that the runtime supports its client, privileges and network requirements. Validate routes, DNS, firewall rules and license checkout from the instance.
2. SSH tunnel via a bastion
   Use a bastion explicitly approved by your organization. Confirm that the licensing protocol and client work through forwarded ports; access to an arbitrary internal host is not authorization.
3. No approved private path
   Ask IT and the vendor to establish a supported connection before proceeding. Do not substitute publicly exposed license ports.

Choose compute resources for a supported solver setup

Check license entitlement, solver requirements and current Compute capacity before launch. Select a compatible environment and review the price shown in the console.

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Step 1: Confirm the license system and required ports with IT

For FlexNet, identify the lmgrd and vendor daemon ports. Ansys can also require a Licensing Interconnect port. DSLS has a separate server and client configuration; do not apply these FlexNet examples to it.

Examples

• Ansys: lmgrd uses 1055 by default; 1056 is an example fixed ansyslmd port. Include Licensing Interconnect, normally 2325, where the product configuration requires it.
• COMSOL: the documented default ports are 1718 for lmgrd and 1719 for LMCOMSOL. This guide’s 27000/27001 examples are custom ports that must match your approved license-server configuration.
• Abaqus: 27002/27003 are custom FlexNet examples only. A DSLS installation needs the DSLS client configuration supplied by your administrator instead.

For an authorized Ansys FlexNet change, IT should follow the vendor’s procedure, preserve the original file and set the approved ports. The following is only the relevant SERVER/VENDOR excerpt:

SERVER <hostname> <hostid> 1055
VENDOR ansyslmd PORT=1056


Have IT restart and test the service according to the vendor procedure after approved changes. Coordinate the change with users; it can interrupt license access.

Tip: keep a short README next to the license file with the pinned ports and who to contact.

Step 2: Choose a compatible runtime

Check the solver version’s supported operating system, libraries, driver and GPU requirements as well as its license terms. A CUDA version alone does not establish solver compatibility. Then choose an available Compute runtime that satisfies those requirements:

• Virtual machine when the supported setup needs full OS control, sudo, system packages or VPN configuration. Confirm the exact OS and solver requirements before launch.
• Container template when its prepared environment satisfies the solver and connection requirements. Compute containers do not provide root access; an arbitrary image is not proof of compatibility.

Configure the licensed solver client using the vendor’s supported environment variables or configuration files. Validate that the selected connection method works in that runtime.

Step 3 — Make the connection from the instance

Option A · VPN (recommended when available)

After IT approves and configures the VPN, test DNS, routing and every required port from the instance. The command below tests one example Ansys port; it does not prove license checkout or contractual permission:

nc -vz licenses.my-org.edu 1055


Option B · SSH tunnels via a bastion

From inside the instance, and only for a setup approved for SSH forwarding, connect through the organization’s designated bastion. This example includes Ansys ports 1055, 1056 and 2325; replace the hostnames and ports with IT’s values:

ssh -N -o ExitOnForwardFailure=yes \
 -L 127.0.0.1:1055:licenses.my-org.edu:1055 \
 -L 127.0.0.1:1056:licenses.my-org.edu:1056 -L 127.0.0.1:2325:licenses.my-org.edu:2325 \
 user@bastion.my-org.edu


Keep the tunnel running during the test. Where the vendor supports this setup, the example FlexNet endpoint is 1055@localhost. For Ansys, configure the corresponding Licensing Interconnect endpoint as required. A successful port forward does not prove checkout; server naming or vendor protocol behavior may require an approved VPN instead.

For another vendor, forward only its documented, approved ports and use its supported client configuration. Do not assume the Ansys example also configures COMSOL or DSLS.

Step 4 — Point the solver to the license server

Configure each client in its supported job environment or vendor configuration file. The examples below distinguish shell exports from Abaqus environment-file settings. Keep credentials and license files out of reusable images; a generic Compute UI setting does not replace the vendor’s installation procedure.

• Ansys
• export ANSYSLMD_LICENSE_FILE=1055@licenses.my-org.edu
export ANSYSLI_SERVERS=2325@licenses.my-org.edu

• COMSOL
• export LMCOMSOL_LICENSE_FILE=27000@licenses.my-org.edu

• Abaqus 2025 with FlexNet: environment-file settings, not shell exports
• license_server_type=FLEXNET
abaquslm_license_file="27002@licenses.my-org.edu"

• Generic FlexNet fallback, only when the vendor supports it
• export LM_LICENSE_FILE=1055@licenses.my-org.edu


For a supported tunnel, the client endpoint may use localhost and the forwarded local ports; validate a real checkout. The Abaqus 2025 manual’s licensing procedure (Virginia Tech mirror) specifies install_dir/os/SMA/site/custom_v6.env and the unquoted constant license_server_type=FLEXNET. Confirm the file and settings for your installed version with the administrator. With DSLS, use its separate configuration, including DSLicSrv.txt; do not apply the FlexNet settings above.

Step 5 — Test

• For the tunnel example, check the local port below, then test every required port. For a VPN, use the actual server hostname and configured ports:
• nc -vz localhost 1055

• Start a tiny solver job to force a checkout.
• Where available, use the vendor’s status tool (lmutil lmstat or GUI) from your admin machine to confirm the seat is checked out by the instance hostname.

Common patterns and notes

• Floating vs elastic: eligibility and setup depend on the product, agreement and hosting arrangement. Do not assume that an existing license, token pack or elastic plan can be used on every cloud provider. Confirm the intended use with the administrator or vendor first.
• Time‑zone skew: clocks too far apart can confuse license checks. Sync with NTP.
• Hostname mismatches: some licenses lock to hostnames; always reference the server by the name in the license file.
• Don’t embed license files in images. Mount or reference them by env vars.

Security checklist

• Use an approved VPN or validated SSH tunnels; do not expose raw license ports publicly.
• On the approved network path, allowlist only the necessary sources and destination ports under IT’s policy.
• Rotate bastion keys. Disable password SSH logins.
• Log license checkouts and review unusual activity.

Troubleshooting

Client can’t reach server
Wrong host/port, firewall, or tunnel down. Test with nc -vz on the exact ports you pinned.

FlexNet -5, -18 and -96 errors
These codes are not interchangeable. -5 concerns a missing feature, -18 an unsupported feature on the license server, and -96 an unavailable or nonresponding license server. Record the complete error and ask IT to check the corresponding license, service and network evidence.

Intermittent drops
NAT/idle timeouts on the path. Keep a small keep‑alive SSH tunnel or use VPN.

“License server system does not support this feature”
Have IT check the requested feature, available entitlement, selected server and relevant version requirements. Do not assume the daemon is the cause or update a shared server without the vendor procedure.

Multiple vendors at once
For FlexNet license search paths, use a colon on Unix/Linux or a semicolon on Windows, or use supported vendor-specific settings. Redundant-server groups have different syntax; follow the vendor’s instructions.

Quick references: client settings

# Ansys shell environment; endpoints depend on your setup
export ANSYSLMD_LICENSE_FILE=1055@licenses.my-org.edu
export ANSYSLI_SERVERS=2325@licenses.my-org.edu
# Abaqus FlexNet: use the version-specific environment file in Step 4.
# Do not run the Abaqus settings as shell commands or apply them to DSLS.
# COMSOL shell environment; 27000 is a custom example port
export LMCOMSOL_LICENSE_FILE=27000@licenses.my-org.edu
# Generic FlexNet shell environment, only if supported by the vendor
export LM_LICENSE_FILE=1055@licenses.my-org.edu


Where GPUs help in these tools (short version)

• Fluent (Ansys): Native GPU solver; coverage keeps growing. Validate your physics model on a sample case.
• Mechanical/Abaqus: Gains depend on element types and solver path; test with your model.
• COMSOL: GPU acceleration exists for specific study types; check your study before moving production.

For deeper guidance, see the scientific-modeling pillar and our guides to Ansys Fluent, COMSOL 6.3, Abaqus, and OpenFOAM.

Methods snippet (keep with your run)

licenses:
 pattern: "vpn | ssh-tunnel" # record the approved, tested choice
 server: "licenses.my-org.edu"
 ports: # Ansys example; also record Licensing Interconnect 2325 if required
   lmgrd: 1055
   vendor: 1056
 env: # also record ANSYSLI_SERVERS for the approved Ansys setup
   - "ANSYSLMD_LICENSE_FILE=1055@licenses.my-org.edu"
compute:
 template: "<verified runtime and solver-supported OS/version>"
 instance: "<gpu model / vram>"
notes: "<entitlement approval, license system/version, extra ports, actual checkout result>"


Related reading

• Scientific modeling on cloud GPUs — what works, what doesn’t

Try Compute today

Before launching, review the Compute FAQ and check current capacity and pricing in the console. Confirm license entitlement and client settings with your administrator, then use the approved VPN or a vendor-compatible SSH tunnel. Ask the solver vendor about licensing and supported configurations. This guide does not promise that Hivenet will configure or support a particular solver-license integration.

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