Configuring ADSKFLEX Options File for AutoCAD Network License Management

Configuring ADSKFLEX Options File for AutoCAD Network License Management

I've been managing Autodesk network licenses for over a decade, and I still remember the chaos before I learned how to properly configure the ADSKFLEX options file. We had 30 AutoCAD licenses and 45 users — every morning was a race to see who grabbed a license first. Once I figured out the .opt file, I could reserve licenses by team, set timeouts for idle users, and actually manage who got access to what. Let me walk you through everything I've learned about configuring it.

Understanding the Options File Location

The options file must be named to match the VENDOR line in your license file. For Autodesk products, the vendor daemon is adskflex, so the options file is named adskflex.opt.

Locating the License File

1. On the license server, open LMTOOLS (typically at C:\Autodesk\Network License Manager\lmtools.exe).
2. Go to the "Config Services" tab.
3. Note the path in the "Path to the license file" field (typically C:\Autodesk\Network License Manager\License\license.lic).
4. Open the .lic file in a text editor (Notepad++ recommended for preserving encoding).
5. Locate the VENDOR line:

   VENDOR adskflex port=2080
   

6. The options file path is: C:\Autodesk\Network License Manager\adskflex.opt

If the options file does not exist, create it as a plain text file with UTF-8 or ANSI encoding. Do not use Unicode encoding — the FLEXlm parser does not handle BOM markers correctly.

Basic Options File Syntax

Every line in the options file is a directive. Comments start with #. Blank lines are ignored. Here is a minimal options file:

# adskflex.opt — AutoCAD Network License Options
# Created: 2026-06-25
# Admin: IT Department

# Set a 2-hour timeout for inactive licenses
TIMEOUTALL 7200

# Log all license checkouts to a daily log file
REPORTLOG "C:\Autodesk\Logs\adskflex_%Y%m%d.log"

Configuring License Groups

Groups allow you to manage license access by team or department rather than individual users.

Define User Groups

GROUP Architects alice.chen bob.smith carlos.rivera
GROUP Engineers dave.kim eve.johnson frank.lee
GROUP Drafters grace.wang henry.park iris.tan
GROUP Contractors jake.miller kelly.norris leo.ota

Group names are case-insensitive. Usernames must match the Windows login name (domain\username format for domain accounts):

GROUP Architects CORP\alice.chen CORP\bob.smith CORP\carlos.rivera

Reserve Licenses per Group

The RESERVE directive guarantees that a specified number of licenses are always available for a particular group:

RESERVE 5 64300ACD_2026 GROUP Architects
RESERVE 3 64300ACD_2026 GROUP Engineers
RESERVE 2 64300ACD_2026 GROUP Drafters

The feature code 64300ACD_2026 corresponds to AutoCAD 2026. To find the exact feature code for your product, run:

lmutil lmstat -a -c C:\Autodesk\Network License Manager\License\license.lic

This displays all feature codes and their current usage.

Set Maximum License Usage

The MAX directive limits how many licenses a group can consume, preventing one department from exhausting the pool:

MAX 8 64300ACD_2026 GROUP Engineers
MAX 3 64300ACD_2026 GROUP Contractors

With this configuration, even if 20 engineers are logged in, they can never check out more than 8 AutoCAD licenses simultaneously.

Configuring License Borrowing

License borrowing allows users to check out a license for offline use. The MAX_BORROW_HOURS directive controls the maximum borrow duration:

MAX_BORROW_HOURS 64300ACD_2026 72

This sets the maximum borrow period to 72 hours. Users can borrow for shorter periods, but not longer.

Restrict Borrowing to Specific Groups

INCLUDE_BORROW 64300ACD_2026 GROUP Architects
EXCLUDE_BORROW 64300ACD_2026 GROUP Contractors

This allows architects to borrow licenses for site visits but prevents contractors from taking licenses off-site.

Configuring Timeouts

When a user closes AutoCAD improperly (crash, network drop, force quit), the license remains checked out until the FLEXlm timeout expires. Setting an appropriate timeout reclaims orphaned licenses quickly.

Global Timeout

TIMEOUTALL 7200

This sets a 2-hour (7200-second) idle timeout for all features. After 2 hours of inactivity, the license is reclaimed and returned to the pool.

Per-Feature Timeout

TIMEOUT 64300ACD_2026 3600
TIMEOUT 85545ACD_2026 7200

The first line sets a 1-hour timeout for AutoCAD 2026; the second sets a 2-hour timeout for AutoCAD LT 2026. Per-feature timeouts override TIMEOUTALL.

Setting the Timeout Value

• Office environments: 3600-7200 seconds (1-2 hours). Users are typically at their desks and can re-checkout quickly.
• Remote/WFH environments: 14400 seconds (4 hours). Network drops are more frequent, and users may be away from their machines during long renders.
• Contractor environments: 1800 seconds (30 minutes). Contractors should release licenses promptly when not actively drafting.

Excluding Users

The EXCLUDE directive blocks specific users from checking out a license:

EXCLUDE 64300ACD_2026 USER terminated.employee
EXCLUDE 64300ACD_2026 USER expired_contractor

This is useful for revoking access without modifying group memberships. Excluded users receive "License checkout failed" when launching AutoCAD.

Creating a Borrowing Deny List

To prevent specific users from borrowing while still allowing them to use licenses on-site:

EXCLUDE_BORROW 64300ACD_2026 USER intern.user
EXCLUDE_BORROW 64300ACD_2026 GROUP Contractors

Logging and Monitoring

Enable Detailed Logging

REPORTLOG "C:\Autodesk\Logs\adskflex_%Y%m%d.log"
DEBUGLOG "C:\Autodesk\Logs\adskflex_debug.log"

REPORTLOG creates a daily log file with checkout/checkin events. The %Y%m%d format creates a new file each day (e.g., adskflex_20260625.log).

DEBUGLOG captures verbose diagnostic information, useful for troubleshooting license denial issues. Enable this only during diagnosis — the debug log grows rapidly.

Monitor Current Usage

Create a batch file for quick license status checks:

@echo off
"C:\Autodesk\Network License Manager\lmutil.exe" lmstat -a -c "C:\Autodesk\Network License Manager\License\license.lic"
pause

Save as check_licenses.bat on the license server desktop. This shows:

• All features and their total/available counts
• Users currently holding licenses
• Borrowed licenses and their return dates

Advanced: License Priority with INCLUDE

When license inventory is limited, the INCLUDE directive creates a priority list. Only listed users or groups can check out the specified feature:

INCLUDE 64300ACD_2026 GROUP Architects
INCLUDE 64300ACD_2026 GROUP Engineers
INCLUDE 64300ACD_2026 GROUP Drafters

Users not in any listed group are denied. This is more restrictive than MAX and should be used when you need to guarantee that only authorized teams access specific license types.

Applying and Testing Changes

After editing the options file:

1. Open LMTOOLS.
2. Go to the "Server Status" tab.
3. Click "Perform Status Enquiry."
4. Verify the options file is loaded — the output should include:

   Options file: C:\Autodesk\Network License Manager\adskflex.opt
   

5. If the options file is not listed, go to "Start/Stop/Reread" and click "ReRead License File."
6. Check the log for syntax errors. Common errors:
   • Line 15: Unknown keyword — check for typos in directive names
   • Line 23: Group not defined — the group name in RESERVE does not match the GROUP definition
   • Line 31: Invalid feature name — the feature code does not match any feature in the license file

Common Configuration Template

Here is a complete options file template for a mid-size firm with 25 AutoCAD licenses:

# adskflex.opt — Enterprise AutoCAD License Configuration
# Created: 2026-06-25

# === Groups ===
GROUP Architects CORP\alice.chen CORP\bob.smith CORP\carlos.rivera CORP\diana.wu
GROUP Engineers CORP\dave.kim CORP\eve.johnson CORP\frank.lee CORP\george.hall
GROUP Drafters CORP\grace.wang CORP\henry.park CORP\iris.tan CORP\jack.ross
GROUP Contractors CORP\kelly.norris CORP\leo.ota

# === Reservations ===
RESERVE 8 64300ACD_2026 GROUP Architects
RESERVE 6 64300ACD_2026 GROUP Engineers
RESERVE 4 64300ACD_2026 GROUP Drafters

# === Limits ===
MAX 3 64300ACD_2026 GROUP Contractors
MAX_BORROW_HOURS 64300ACD_2026 72

# === Borrowing ===
INCLUDE_BORROW 64300ACD_2026 GROUP Architects
INCLUDE_BORROW 64300ACD_2026 GROUP Engineers
EXCLUDE_BORROW 64300ACD_2026 GROUP Contractors

# === Timeouts ===
TIMEOUTALL 7200
TIMEOUT 64300ACD_2026 3600

# === Logging ===
REPORTLOG "C:\Autodesk\Logs\adskflex_%Y%m%d.log"

This configuration ensures that architects always have 8 licenses available, engineers have 6, and drafters have 4, while contractors are limited to 3 concurrent uses with no borrowing privileges. Idle licenses are reclaimed after 1 hour for AutoCAD and 2 hours for all other Autodesk products.