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LS-DYNA Troubleshooting

This guide provides comprehensive troubleshooting procedures for LSTC license servers and LS-DYNA-specific issues. The Vantage License Manager includes advanced diagnostic tools and automated troubleshooting features specifically designed for LS-DYNA solver environments, parallel token management, and high-performance computing integrations.

Common LS-DYNA License Issues​

License Acquisition Failures​

Symptom: LS-DYNA solver cannot acquire license

# Error message examples:
ERROR: No license available for LS-DYNA solver
ERROR: LSTC license server not responding
ERROR: Parallel tokens exhausted for SMP/MPP simulation

Diagnosis Steps:

import textwrap
import subprocess
import json
from datetime import datetime

def diagnose_license_acquisition():
    """Comprehensive LS-DYNA license acquisition diagnostics."""
    
    diagnostic_script = textwrap.dedent("""
        #!/bin/bash
        # LS-DYNA License Acquisition Diagnostic Script
        
        echo "=== LS-DYNA License Acquisition Diagnostics ==="
        echo "Timestamp: $(date)"
        echo
        
        # Test LSTC server connectivity
        echo "Testing LSTC server connectivity:"
        for server in lstc-server.company.com lstc-backup.company.com; do
            echo -n "  $server:31010 - "
            if timeout 10 telnet $server 31010 </dev/null >/dev/null 2>&1; then
                echo "CONNECTED"
            else
                echo "FAILED"
            fi
        done
        echo
        
        # Check license server status
        echo "LSTC server status:"
        /opt/lstc/bin/lstc_qstat -s 31010@lstc-server.company.com 2>&1
        echo
        
        # Check solver availability
        echo "LS-DYNA solver availability:"
        for solver in explicit implicit em thermal; do
            echo -n "  $solver: "
            if /opt/lstc/bin/lstc_qrun -info -solver $solver -s 31010@lstc-server.company.com >/dev/null 2>&1; then
                echo "AVAILABLE"
            else
                echo "UNAVAILABLE"
            fi
        done
        echo
        
        # Check parallel token status
        echo "Parallel token status:"
        /opt/lstc/bin/lstc_qstat -t -s 31010@lstc-server.company.com 2>&1
        echo
        
        # Test license checkout
        echo "Testing license checkout:"
        /opt/lstc/bin/lstc_qrun -checkout -solver explicit -ncpu 1 -s 31010@lstc-server.company.com
        echo
        """).strip()
    
    # Write and execute diagnostic script
    with open('/tmp/lstc_diagnostics.sh', 'w') as f:
        f.write(diagnostic_script)
    
    subprocess.run(['chmod', '+x', '/tmp/lstc_diagnostics.sh'])
    result = subprocess.run(['/tmp/lstc_diagnostics.sh'], 
                          capture_output=True, text=True)
    
    return result.stdout

# Run diagnostics
diagnostic_output = diagnose_license_acquisition()
print(diagnostic_output)

Resolution Steps:

  1. Verify Server Connectivity:
# Test LSTC server network connectivity
telnet lstc-server.company.com 31010
telnet lstc-server.company.com 31011  # Parallel token port

# Check DNS resolution
nslookup lstc-server.company.com

# Test with Vantage CLI
vantage licenses test-connectivity lsdyna-production \
  --server lstc-server.company.com:31010 \
  --test-solvers explicit,implicit,em,thermal \
  --test-parallel-tokens
  1. Check License Availability:
# Query available licenses
/opt/lstc/bin/lstc_qstat -s 31010@lstc-server.company.com

# Check specific solver licenses
for solver in explicit implicit em thermal; do
    echo "Checking $solver solver licenses:"
    /opt/lstc/bin/lstc_qrun -info -solver "$solver" -s 31010@lstc-server.company.com
done

# Verify license file integrity
/opt/lstc/bin/lstc_verify -license /opt/lstc/licenses/lstc.lic
  1. Parallel Token Issues:
# Check parallel token availability
/opt/lstc/bin/lstc_qstat -t -s 31010@lstc-server.company.com

# Test SMP token allocation
/opt/lstc/bin/lstc_qrun -checkout -solver explicit -ncpu 8 -s 31010@lstc-server.company.com

# Test MPP token allocation
/opt/lstc/bin/lstc_qrun -checkout -solver explicit -ncpu 16 -parallel mpp -s 31010@lstc-server.company.com

Solver-Specific Issues​

LS-DYNA Explicit Solver Problems:

import textwrap
import re
from pathlib import Path

def troubleshoot_explicit_solver():
    """Troubleshoot LS-DYNA Explicit solver issues."""
    
    troubleshooting_script = textwrap.dedent("""
        #!/bin/bash
        # LS-DYNA Explicit Solver Troubleshooting
        
        echo "=== LS-DYNA Explicit Solver Diagnostics ==="
        
        # Check explicit solver license
        echo "Explicit solver license status:"
        /opt/lstc/bin/lstc_qrun -info -solver explicit -s 31010@lstc-server.company.com
        echo
        
        # Verify solver binary
        echo "LS-DYNA explicit binary verification:"
        if [ -f /opt/lsdyna/bin/lsdyna ]; then
            /opt/lsdyna/bin/lsdyna -h | head -10
            echo "Binary version: $(/opt/lsdyna/bin/lsdyna -h | grep -i version)"
        else
            echo "ERROR: LS-DYNA binary not found at /opt/lsdyna/bin/lsdyna"
        fi
        echo
        
        # Check environment variables
        echo "LS-DYNA environment variables:"
        echo "LSTC_LICENSE: ${LSTC_LICENSE:-NOT SET}"
        echo "LSTC_LICENSE_SERVER: ${LSTC_LICENSE_SERVER:-NOT SET}"
        echo "LSDYNA_EXECUTABLE: ${LSDYNA_EXECUTABLE:-NOT SET}"
        echo
        
        # Test simple explicit job
        echo "Testing simple explicit job:"
        cat > /tmp/test_explicit.k << 'EOF'
*KEYWORD
*TITLE
Simple LS-DYNA Explicit Test
*CONTROL_TERMINATION
$#  endtim    endcyc     dtmin    endeng    endmas     nosol
       1.0         0       0.0       0.0       0.0         0
*DATABASE_BINARY_D3PLOT
$#      dt      lcdt      beam     npltc    psetid
       0.1         0         0         0         0
*END
EOF
        
        # Attempt to run test job
        cd /tmp
        timeout 60 /opt/lsdyna/bin/lsdyna i=test_explicit.k
        
        if [ $? -eq 0 ]; then
            echo "Explicit solver test: PASSED"
        else
            echo "Explicit solver test: FAILED"
            echo "Check d3hsp file for detailed error messages"
        fi
        """).strip()
    
    return troubleshooting_script

# Generate and save troubleshooting script
script_content = troubleshoot_explicit_solver()
with open('/tmp/explicit_troubleshoot.sh', 'w') as f:
    f.write(script_content)

print("Explicit solver troubleshooting script created at /tmp/explicit_troubleshoot.sh")

LS-DYNA Implicit Solver Problems:

import textwrap

def troubleshoot_implicit_solver():
    """Troubleshoot LS-DYNA Implicit solver issues."""
    
    implicit_diagnostics = textwrap.dedent("""
        #!/bin/bash
        # LS-DYNA Implicit Solver Troubleshooting
        
        echo "=== LS-DYNA Implicit Solver Diagnostics ==="
        
        # Check implicit solver license and capabilities
        echo "Implicit solver license status:"
        /opt/lstc/bin/lstc_qrun -info -solver implicit -s 31010@lstc-server.company.com
        echo
        
        # Verify implicit solver availability
        echo "Testing implicit solver checkout:"
        /opt/lstc/bin/lstc_qrun -checkout -solver implicit -ncpu 4 -s 31010@lstc-server.company.com
        checkout_status=$?
        
        if [ $checkout_status -eq 0 ]; then
            echo "Implicit solver checkout: SUCCESS"
            # Release the license
            /opt/lstc/bin/lstc_qrun -release -solver implicit -s 31010@lstc-server.company.com
        else
            echo "Implicit solver checkout: FAILED (Status: $checkout_status)"
        fi
        echo
        
        # Check for common implicit solver issues
        echo "Common implicit solver issues check:"
        
        # Check for required libraries
        echo "Checking required libraries:"
        for lib in libmkl_rt.so libiomp5.so; do
            if ldconfig -p | grep -q "$lib"; then
                echo "  $lib: FOUND"
            else
                echo "  $lib: MISSING - may cause implicit solver issues"
            fi
        done
        echo
        
        # Check memory requirements
        echo "Memory requirements check:"
        total_mem=$(free -g | awk '/^Mem:/{print $2}')
        echo "  Total system memory: ${total_mem}GB"
        if [ "$total_mem" -lt 8 ]; then
            echo "  WARNING: Implicit solver may require more memory for large models"
        fi
        echo
        
        # Test simple implicit job
        echo "Testing simple implicit job:"
        cat > /tmp/test_implicit.k << 'EOF'
*KEYWORD
*TITLE
Simple LS-DYNA Implicit Test
*CONTROL_IMPLICIT_GENERAL
$#   imflag       dt0    imform      nsbs       igs     cnstn      form    zero_v
         1       0.0         2         1         2         0         0         0
*CONTROL_TERMINATION
$#  endtim    endcyc     dtmin    endeng    endmas     nosol
       1.0        10       0.0       0.0       0.0         0
*DATABASE_BINARY_D3PLOT
$#      dt      lcdt      beam     npltc    psetid
       0.2         0         0         0         0
*END
EOF
        
        echo "Implicit test job created at /tmp/test_implicit.k"
        """).strip()
    
    return implicit_diagnostics

# Create implicit troubleshooting script
implicit_script = troubleshoot_implicit_solver()
print("Implicit solver troubleshooting procedures ready")

Parallel Token Exhaustion​

Symptom: Parallel simulations fail due to insufficient tokens

import textwrap
import json

def diagnose_parallel_token_exhaustion():
    """Diagnose and resolve parallel token exhaustion issues."""
    
    token_diagnostic_script = textwrap.dedent("""
        #!/bin/bash
        # LS-DYNA Parallel Token Exhaustion Diagnostics
        
        echo "=== Parallel Token Exhaustion Diagnostics ==="
        echo "Timestamp: $(date)"
        echo
        
        # Get current token usage
        echo "Current parallel token usage:"
        /opt/lstc/bin/lstc_qstat -t -s 31010@lstc-server.company.com
        echo
        
        # Check token allocation by user
        echo "Token allocation by user:"
        /opt/lstc/bin/lstc_qstat -u -s 31010@lstc-server.company.com | grep -E "(SMP|MPP)"
        echo
        
        # Check token allocation by job
        echo "Active jobs using parallel tokens:"
        /opt/lstc/bin/lstc_qstat -j -s 31010@lstc-server.company.com | grep -E "(SMP|MPP)"
        echo
        
        # Check maximum available tokens
        echo "Maximum available parallel tokens:"
        /opt/lstc/bin/lstc_qrun -info -parallel all -s 31010@lstc-server.company.com
        echo
        
        # Check for stuck tokens
        echo "Checking for potentially stuck parallel tokens:"
        /opt/lstc/bin/lstc_qstat -stuck -s 31010@lstc-server.company.com
        echo
        
        # Generate token usage report
        echo "Generating token usage summary:"
        python3 << 'PYTHON_EOF'
import subprocess
import re
from datetime import datetime, timedelta

def analyze_token_usage():
    # Get token status
    result = subprocess.run(['/opt/lstc/bin/lstc_qstat', '-t', '-s', '31010@lstc-server.company.com'], 
                          capture_output=True, text=True)
    
    if result.returncode != 0:
        print(f"Error getting token status: {result.stderr}")
        return
    
    output = result.stdout
    lines = output.strip().split('\\n')
    
    smp_total = smp_used = 0
    mpp_total = mpp_used = 0
    
    for line in lines:
        if 'SMP' in line:
            # Parse SMP token information
            match = re.search(r'SMP.*?(\d+)/(\d+)', line)
            if match:
                smp_used, smp_total = map(int, match.groups())
        elif 'MPP' in line:
            # Parse MPP token information
            match = re.search(r'MPP.*?(\d+)/(\d+)', line)
            if match:
                mpp_used, mpp_total = map(int, match.groups())
    
    print(f"SMP Tokens: {smp_used}/{smp_total} used ({(smp_used/smp_total*100):.1f}%)")
    print(f"MPP Tokens: {mpp_used}/{mpp_total} used ({(mpp_used/mpp_total*100):.1f}%)")
    
    # Check if tokens are near exhaustion
    if smp_used / smp_total > 0.9:
        print("WARNING: SMP tokens are near exhaustion (>90% used)")
    if mpp_used / mpp_total > 0.9:
        print("WARNING: MPP tokens are near exhaustion (>90% used)")

analyze_token_usage()
PYTHON_EOF
        """).strip()
    
    return token_diagnostic_script

# Generate token diagnostics
token_script = diagnose_parallel_token_exhaustion()
print("Parallel token diagnostic script generated")

Resolution Strategies:

  1. Increase Token Pool Size:
# Check current license configuration
vantage licenses show lsdyna-production --include-tokens

# Request additional parallel tokens (contact LSTC)
vantage licenses request-tokens lsdyna-production \
  --smp-tokens 64 \
  --mpp-tokens 32 \
  --justification "Increased LS-DYNA parallel simulation demands"

# Configure token pooling
vantage licenses configure-tokens lsdyna-production \
  --enable-token-sharing \
  --enable-dynamic-allocation \
  --smp-pool-priority high \
  --mpp-pool-priority medium
  1. Optimize Token Usage:
# Monitor token utilization patterns
vantage licenses analyze-token-usage lsdyna-production \
  --period last-30-days \
  --breakdown-by user,solver,time-of-day \
  --identify-optimization-opportunities

# Set up token usage policies
vantage licenses token-policies lsdyna-production \
  --max-smp-per-user 16 \
  --max-mpp-per-user 8 \
  --max-total-tokens-per-user 24 \
  --priority-users "simulation-leads@company.com" \
  --queue-timeout 300
  1. Release Stuck Tokens:
# Identify and release stuck tokens
/opt/lstc/bin/lstc_qstat -stuck -s 31010@lstc-server.company.com

# Force release specific tokens (use with caution)
/opt/lstc/bin/lstc_qrun -release -force -user username -s 31010@lstc-server.company.com

# Clean up orphaned token allocations
vantage licenses cleanup-tokens lsdyna-production \
  --release-orphaned \
  --release-expired \
  --max-idle-time 1h

Server-Side Issues​

LSTC Server Startup Problems​

Symptom: LSTC license server fails to start

import textwrap
import os
import subprocess

def diagnose_server_startup():
    """Diagnose LSTC server startup issues."""
    
    startup_diagnostic = textwrap.dedent("""
        #!/bin/bash
        # LSTC Server Startup Diagnostics
        
        echo "=== LSTC Server Startup Diagnostics ==="
        
        # Check service status
        echo "LSTC service status:"
        systemctl status lstc-server 2>&1
        echo
        
        # Check server logs
        echo "Recent LSTC server logs:"
        tail -50 /opt/lstc/logs/lstc_server.log 2>/dev/null || echo "Log file not found"
        echo
        
        # Check configuration file
        echo "Configuration file validation:"
        if [ -f /opt/lstc/config/lstc.conf ]; then
            echo "Configuration file exists"
            /opt/lstc/bin/lstc_server -test-config /opt/lstc/config/lstc.conf
        else
            echo "ERROR: Configuration file missing at /opt/lstc/config/lstc.conf"
        fi
        echo
        
        # Check license file
        echo "License file validation:"
        if [ -f /opt/lstc/licenses/lstc.lic ]; then
            echo "License file exists"
            /opt/lstc/bin/lstc_verify -license /opt/lstc/licenses/lstc.lic
        else
            echo "ERROR: License file missing at /opt/lstc/licenses/lstc.lic"
        fi
        echo
        
        # Check ports
        echo "Port availability check:"
        for port in 31010 31011; do
            if netstat -tln | grep -q ":$port "; then
                echo "  Port $port: IN USE (may conflict)"
                netstat -tlnp | grep ":$port "
            else
                echo "  Port $port: AVAILABLE"
            fi
        done
        echo
        
        # Check file permissions
        echo "File permissions check:"
        ls -la /opt/lstc/bin/lstc_server
        ls -la /opt/lstc/config/lstc.conf
        ls -la /opt/lstc/licenses/lstc.lic
        echo
        
        # Check system resources
        echo "System resources:"
        echo "  Memory: $(free -h | grep Mem: | awk '{print $2}') total, $(free -h | grep Mem: | awk '{print $3}') used"
        echo "  Disk space: $(df -h /opt/lstc | tail -1 | awk '{print $4}') available"
        echo "  Load average: $(uptime | awk -F'load average:' '{print $2}')"
        """).strip()
    
    return startup_diagnostic

# Create server startup diagnostic script
startup_script = diagnose_server_startup()
print("Server startup diagnostic script ready")

Common Startup Issues:

  1. Port Conflicts:
# Check what's using LSTC ports
sudo netstat -tlnp | grep -E ":(31010|31011) "
sudo lsof -i :31010
sudo lsof -i :31011

# Kill conflicting processes (if safe)
sudo kill -9 $(lsof -t -i:31010)
sudo kill -9 $(lsof -t -i:31011)

# Configure alternative ports if needed
sudo -u lstc tee -a /opt/lstc/config/lstc.conf <<EOF
PORT 31020
PARALLEL_TOKEN_PORT 31021
EOF
  1. Permission Issues:
# Fix LSTC file permissions
sudo chown -R lstc:lstc /opt/lstc/
sudo chmod 755 /opt/lstc/bin/lstc_server
sudo chmod 644 /opt/lstc/config/lstc.conf
sudo chmod 644 /opt/lstc/licenses/lstc.lic
sudo chmod 755 /opt/lstc/logs/

# Verify SELinux context (if applicable)
sudo restorecon -R /opt/lstc/
  1. License File Issues:
# Validate license file format
/opt/lstc/bin/lstc_verify -license /opt/lstc/licenses/lstc.lic -verbose

# Check license expiration
/opt/lstc/bin/lstc_info -license /opt/lstc/licenses/lstc.lic | grep -i expir

# Verify license file integrity
md5sum /opt/lstc/licenses/lstc.lic

Performance Issues​

Symptom: Slow license acquisition or solver startup

import textwrap
import time
import subprocess

def diagnose_performance_issues():
    """Diagnose LSTC server performance issues."""
    
    performance_diagnostic = textwrap.dedent("""
        #!/bin/bash
        # LSTC Server Performance Diagnostics
        
        echo "=== LSTC Server Performance Diagnostics ==="
        
        # Measure license checkout time
        echo "Measuring license checkout performance:"
        for i in {1..5}; do
            echo -n "  Attempt $i: "
            start_time=$(date +%s.%N)
            if /opt/lstc/bin/lstc_qrun -checkout -solver explicit -ncpu 1 -s 31010@lstc-server.company.com >/dev/null 2>&1; then
                end_time=$(date +%s.%N)
                duration=$(echo "$end_time - $start_time" | bc)
                echo "${duration}s"
                /opt/lstc/bin/lstc_qrun -release -solver explicit -s 31010@lstc-server.company.com >/dev/null 2>&1
            else
                echo "FAILED"
            fi
            sleep 1
        done
        echo
        
        # Check server load
        echo "Server performance metrics:"
        echo "  CPU usage: $(top -bn1 | grep "Cpu(s)" | awk '{print $2}' | cut -d'%' -f1)%"
        echo "  Memory usage: $(free | grep Mem | awk '{printf "%.1f%%", $3/$2 * 100.0}')"
        echo "  Load average: $(uptime | awk -F'load average:' '{print $2}')"
        echo "  Disk I/O: $(iostat 1 2 | tail -1 | awk '{print "Read: " $3 " KB/s, Write: " $4 " KB/s"}')"
        echo
        
        # Check network latency
        echo "Network latency to LSTC server:"
        ping -c 5 lstc-server.company.com | tail -1
        echo
        
        # Check LSTC server internal metrics
        echo "LSTC server internal metrics:"
        /opt/lstc/bin/lstc_qstat -perf -s 31010@lstc-server.company.com 2>/dev/null || echo "Performance metrics not available"
        echo
        
        # Check concurrent connections
        echo "Current LSTC connections:"
        netstat -an | grep :31010 | wc -l
        echo
        
        # Check log file sizes
        echo "Log file sizes:"
        ls -lh /opt/lstc/logs/*.log 2>/dev/null | awk '{print "  " $9 ": " $5}' || echo "No log files found"
        """).strip()
    
    return performance_diagnostic

# Create performance diagnostic script
perf_script = diagnose_performance_issues()
print("Performance diagnostic script ready")

Performance Optimization:

  1. Server Configuration Tuning:
# Optimize LSTC server configuration for performance
sudo -u lstc tee /opt/lstc/config/performance.conf <<EOF
# Performance Configuration
MAX_CONNECTIONS 1000
CONNECTION_TIMEOUT 30
THREAD_POOL_SIZE 50
CACHE_SIZE_LICENSES 5000
CACHE_SIZE_SESSIONS 10000

# LS-DYNA Specific Optimizations
SOLVER_CACHE_ENABLE true
SOLVER_CACHE_SIZE 1000
PARALLEL_TOKEN_CACHE_ENABLE true
PARALLEL_TOKEN_CACHE_SIZE 2000

# Network Optimizations
TCP_NODELAY true
TCP_KEEPALIVE true
SOCKET_BUFFER_SIZE 65536

# Logging Optimizations
LOG_LEVEL info
LOG_ROTATION_SIZE 100MB
LOG_ROTATION_COUNT 10
LOG_ASYNC_ENABLE true
EOF
  1. System-Level Optimizations:
# Optimize system for LSTC performance
echo 'net.core.rmem_default = 262144' | sudo tee -a /etc/sysctl.conf
echo 'net.core.rmem_max = 16777216' | sudo tee -a /etc/sysctl.conf
echo 'net.core.wmem_default = 262144' | sudo tee -a /etc/sysctl.conf
echo 'net.core.wmem_max = 16777216' | sudo tee -a /etc/sysctl.conf
sudo sysctl -p

# Optimize disk I/O
echo 'mq-deadline' | sudo tee /sys/block/sda/queue/scheduler
echo '2048' | sudo tee /sys/block/sda/queue/read_ahead_kb
  1. Database Performance (if using):
# PostgreSQL optimizations for LSTC
sudo -u postgres psql -c "ALTER SYSTEM SET shared_buffers = '256MB';"
sudo -u postgres psql -c "ALTER SYSTEM SET effective_cache_size = '1GB';"
sudo -u postgres psql -c "ALTER SYSTEM SET work_mem = '16MB';"
sudo systemctl restart postgresql

LS-DYNA Solver Issues​

Symptom: LS-DYNA simulations fail with memory errors

import textwrap
import psutil
import os

def diagnose_memory_issues():
    """Diagnose LS-DYNA memory-related issues."""
    
    memory_diagnostic = textwrap.dedent("""
        #!/bin/bash
        # LS-DYNA Memory Issues Diagnostic
        
        echo "=== LS-DYNA Memory Issues Diagnostics ==="
        
        # Check system memory
        echo "System memory status:"
        free -h
        echo
        
        # Check swap usage
        echo "Swap usage:"
        swapon --show
        echo
        
        # Check memory limits
        echo "Memory limits for LSTC user:"
        sudo -u lstc bash -c 'ulimit -a | grep -E "(memory|virtual)"'
        echo
        
        # Check huge pages (for large simulations)
        echo "Huge pages configuration:"
        echo "  Total huge pages: $(cat /proc/sys/vm/nr_hugepages)"
        echo "  Huge page size: $(grep Hugepagesize /proc/meminfo)"
        echo "  Available huge pages: $(grep HugePages_Free /proc/meminfo)"
        echo
        
        # Check for memory leaks in LSTC
        echo "LSTC memory usage:"
        ps aux | grep lstc | grep -v grep
        echo
        
        # Check LS-DYNA solver memory requirements
        echo "LS-DYNA solver memory estimation:"
        python3 << 'PYTHON_EOF'
import os
import subprocess

def estimate_lsdyna_memory():
    # Common LS-DYNA memory requirements
    print("Typical LS-DYNA memory requirements:")
    print("  Small models (< 100K elements): 1-4 GB")
    print("  Medium models (100K-1M elements): 4-16 GB")
    print("  Large models (1M-10M elements): 16-64 GB")
    print("  Very large models (> 10M elements): 64+ GB")
    print()
    
    # Check available memory
    with open('/proc/meminfo', 'r') as f:
        meminfo = f.read()
    
    for line in meminfo.split('\\n'):
        if 'MemAvailable' in line:
            available_kb = int(line.split()[1])
            available_gb = available_kb / 1024 / 1024
            print(f"Available memory for LS-DYNA: {available_gb:.1f} GB")
            
            if available_gb < 4:
                print("WARNING: Limited memory available for LS-DYNA simulations")
            elif available_gb < 16:
                print("NOTICE: Suitable for small to medium LS-DYNA models")
            else:
                print("GOOD: Sufficient memory for large LS-DYNA models")
            break

estimate_lsdyna_memory()
PYTHON_EOF
        
        # Check for OOM killer activity
        echo "Recent out-of-memory events:"
        dmesg | grep -i "killed process" | tail -5
        """).strip()
    
    return memory_diagnostic

# Create memory diagnostic script
memory_script = diagnose_memory_issues()
print("Memory diagnostic script ready")

Memory Issue Resolutions:

  1. Increase System Memory:
# Configure additional swap space
sudo fallocate -l 8G /swapfile
sudo chmod 600 /swapfile
sudo mkswap /swapfile
sudo swapon /swapfile
echo '/swapfile none swap sw 0 0' | sudo tee -a /etc/fstab

# Configure huge pages for large simulations
echo 1024 | sudo tee /proc/sys/vm/nr_hugepages
echo 'vm.nr_hugepages = 1024' | sudo tee -a /etc/sysctl.conf
  1. Optimize LS-DYNA Memory Usage:
# Set memory-related environment variables
export OMP_STACKSIZE=128M
export LSTC_MEMORY_LIMIT=80%
export LSDYNA_MEM_EFFICIENT=1

# Create memory-optimized LS-DYNA wrapper
sudo tee /opt/lsdyna/bin/lsdyna-optimized <<'EOF'
#!/bin/bash
# Memory-optimized LS-DYNA wrapper

# Set memory limits
ulimit -v $(($(free -m | awk '/^Mem:/{print $2}') * 1024 * 80 / 100))  # 80% of RAM
ulimit -s 131072  # 128MB stack size

# Set LS-DYNA memory options
export LSTC_MEMORY_EFFICIENT=1
export OMP_STACKSIZE=128M

# Run LS-DYNA with memory optimizations
exec /opt/lsdyna/bin/lsdyna "$@"
EOF

sudo chmod +x /opt/lsdyna/bin/lsdyna-optimized

Parallel Processing Issues​

Symptom: SMP/MPP simulations fail or perform poorly

import textwrap

def diagnose_parallel_issues():
    """Diagnose LS-DYNA parallel processing issues."""
    
    parallel_diagnostic = textwrap.dedent("""
        #!/bin/bash
        # LS-DYNA Parallel Processing Diagnostics
        
        echo "=== LS-DYNA Parallel Processing Diagnostics ==="
        
        # Check CPU information
        echo "CPU information:"
        echo "  Physical CPUs: $(grep "physical id" /proc/cpuinfo | sort -u | wc -l)"
        echo "  CPU cores: $(nproc)"
        echo "  CPU threads: $(grep -c processor /proc/cpuinfo)"
        echo "  CPU model: $(grep "model name" /proc/cpuinfo | head -1 | cut -d: -f2 | xargs)"
        echo
        
        # Check MPI installation (for MPP)
        echo "MPI installation check:"
        if command -v mpirun >/dev/null 2>&1; then
            echo "  MPI found: $(mpirun --version | head -1)"
            mpirun --version | head -1
        else
            echo "  MPI not found - required for LS-DYNA MPP"
        fi
        echo
        
        # Check OpenMP support (for SMP)
        echo "OpenMP support check:"
        if [ -n "$OMP_NUM_THREADS" ]; then
            echo "  OMP_NUM_THREADS: $OMP_NUM_THREADS"
        else
            echo "  OMP_NUM_THREADS: not set"
        fi
        
        # Test OpenMP
        cat > /tmp/test_openmp.c << 'EOF'
#include <omp.h>
#include <stdio.h>
int main() {
    #pragma omp parallel
    {
        int id = omp_get_thread_num();
        int nthreads = omp_get_num_threads();
        printf("Thread %d of %d\\n", id, nthreads);
    }
    return 0;
}
EOF
        
        if gcc -fopenmp /tmp/test_openmp.c -o /tmp/test_openmp 2>/dev/null; then
            echo "  OpenMP test compilation: SUCCESS"
            /tmp/test_openmp | head -5
        else
            echo "  OpenMP test compilation: FAILED"
        fi
        echo
        
        # Check parallel token availability
        echo "Parallel token availability:"
        /opt/lstc/bin/lstc_qstat -t -s 31010@lstc-server.company.com | grep -E "(SMP|MPP)"
        echo
        
        # Test SMP execution
        echo "Testing SMP parallel execution:"
        export OMP_NUM_THREADS=4
        if timeout 30 /opt/lsdyna/bin/lsdyna -help >/dev/null 2>&1; then
            echo "  SMP test: Basic execution OK"
        else
            echo "  SMP test: Basic execution FAILED"
        fi
        echo
        
        # Check network configuration (for MPP)
        echo "Network configuration for MPP:"
        echo "  Hostname: $(hostname -f)"
        echo "  IP address: $(hostname -I | awk '{print $1}')"
        echo "  Network interfaces:"
        ip addr show | grep -E "^[0-9]+:|inet " | grep -v "127.0.0.1"
        """).strip()
    
    return parallel_diagnostic

# Create parallel processing diagnostic script
parallel_script = diagnose_parallel_issues()
print("Parallel processing diagnostic script ready")

Parallel Processing Resolutions:

  1. SMP (Shared Memory) Issues:
# Configure optimal SMP settings
export OMP_NUM_THREADS=$(nproc)
export OMP_PROC_BIND=true
export OMP_PLACES=cores
export OMP_SCHEDULE=dynamic

# Create SMP-optimized job script
cat > lsdyna_smp_job.sh <<'EOF'
#!/bin/bash
#SBATCH --ntasks=1
#SBATCH --cpus-per-task=16
#SBATCH --mem=32G
#SBATCH --time=24:00:00

# Set SMP environment
export OMP_NUM_THREADS=$SLURM_CPUS_PER_TASK
export OMP_PROC_BIND=true
export OMP_PLACES=cores

# Run LS-DYNA SMP
/opt/lsdyna/bin/lsdyna i=input.k ncpu=$OMP_NUM_THREADS memory=30000m
EOF
  1. MPP (Message Passing) Issues:
# Install and configure MPI
sudo yum install -y openmpi openmpi-devel  # RHEL/CentOS
# or
sudo apt install -y openmpi-bin openmpi-common libopenmpi-dev  # Ubuntu

# Configure MPI environment
echo 'export PATH=/usr/lib64/openmpi/bin:$PATH' >> ~/.bashrc
echo 'export LD_LIBRARY_PATH=/usr/lib64/openmpi/lib:$LD_LIBRARY_PATH' >> ~/.bashrc

# Create MPP-optimized job script
cat > lsdyna_mpp_job.sh <<'EOF'
#!/bin/bash
#SBATCH --ntasks=32
#SBATCH --mem-per-cpu=2G
#SBATCH --time=24:00:00

# Run LS-DYNA MPP
mpirun -np $SLURM_NTASKS /opt/lsdyna/bin/lsdyna-mpp i=input.k memory=1500m
EOF

Integration Issues​

HPC Cluster Integration​

Symptom: LS-DYNA jobs fail to run on HPC clusters

# Diagnose HPC integration issues
vantage clusters test lsdyna-integration \
  --test-license-connectivity \
  --test-solver-availability \
  --test-parallel-tokens \
  --test-job-submission \
  --test-environment-variables

# Check cluster-specific LS-DYNA configuration
vantage clusters show-config lsdyna-integration \
  --include-license-settings \
  --include-solver-paths \
  --include-environment-variables

Environment Variable Issues​

import textwrap
import os

def diagnose_environment_issues():
    """Diagnose LS-DYNA environment variable issues."""
    
    env_check_script = textwrap.dedent("""
        #!/bin/bash
        # LS-DYNA Environment Variables Diagnostic
        
        echo "=== LS-DYNA Environment Variables Check ==="
        
        # Check required LS-DYNA environment variables
        echo "Required LS-DYNA environment variables:"
        vars=("LSTC_LICENSE" "LSTC_LICENSE_SERVER" "LSDYNA_EXECUTABLE" "OMP_NUM_THREADS")
        
        for var in "${vars[@]}"; do
            if [ -n "${!var}" ]; then
                echo "  $var: ${!var}"
            else
                echo "  $var: NOT SET (may cause issues)"
            fi
        done
        echo
        
        # Check PATH for LS-DYNA
        echo "PATH contains LS-DYNA:"
        if echo "$PATH" | grep -q lsdyna; then
            echo "  LS-DYNA found in PATH"
            echo "$PATH" | tr ':' '\\n' | grep lsdyna
        else
            echo "  LS-DYNA NOT found in PATH"
        fi
        echo
        
        # Check LD_LIBRARY_PATH
        echo "LD_LIBRARY_PATH for LS-DYNA libraries:"
        if [ -n "$LD_LIBRARY_PATH" ]; then
            echo "  LD_LIBRARY_PATH: $LD_LIBRARY_PATH"
        else
            echo "  LD_LIBRARY_PATH: NOT SET"
        fi
        echo
        
        # Check MPI environment
        echo "MPI environment variables:"
        env | grep -E "^(MPI|OMPI|MPICH)" || echo "  No MPI environment variables set"
        echo
        
        # Check license server connectivity from environment
        echo "Testing license server from environment:"
        if [ -n "$LSTC_LICENSE_SERVER" ]; then
            /opt/lstc/bin/lstc_qstat -s "$LSTC_LICENSE_SERVER" >/dev/null 2>&1
            if [ $? -eq 0 ]; then
                echo "  License server connectivity: OK"
            else
                echo "  License server connectivity: FAILED"
            fi
        else
            echo "  LSTC_LICENSE_SERVER not set"
        fi
        """).strip()
    
    return env_check_script

# Create environment diagnostic script
env_script = diagnose_environment_issues()
print("Environment diagnostic script ready")

Environment Setup:

# Create comprehensive LS-DYNA environment setup
sudo tee /etc/profile.d/lsdyna.sh <<'EOF'
#!/bin/bash
# LS-DYNA Environment Configuration

# License server configuration
export LSTC_LICENSE="31010@lstc-server.company.com"
export LSTC_LICENSE_SERVER="lstc-server.company.com:31010"

# LS-DYNA executable paths
export LSDYNA_ROOT="/opt/lsdyna"
export LSDYNA_EXECUTABLE="$LSDYNA_ROOT/bin/lsdyna"
export PATH="$LSDYNA_ROOT/bin:$PATH"

# OpenMP configuration for SMP
export OMP_NUM_THREADS=$(nproc)
export OMP_PROC_BIND=true
export OMP_PLACES=cores
export OMP_SCHEDULE=dynamic

# MPI configuration for MPP
export MPI_ROOT="/usr/lib64/openmpi"
export PATH="$MPI_ROOT/bin:$PATH"
export LD_LIBRARY_PATH="$MPI_ROOT/lib:$LD_LIBRARY_PATH"

# LS-DYNA specific optimizations
export LSTC_MEMORY_EFFICIENT=1
export LSDYNA_MEM_EFFICIENT=1
export OMP_STACKSIZE=128M
EOF

# Make environment available to all users
sudo chmod +x /etc/profile.d/lsdyna.sh

Vantage Integration Troubleshooting​

Dashboard Connection Issues​

# Test Vantage dashboard connectivity for LS-DYNA
vantage licenses test-dashboard lsdyna-production \
  --test-server-connectivity \
  --test-data-collection \
  --test-real-time-updates \
  --test-alert-delivery

# Refresh dashboard data
vantage licenses refresh-dashboard lsdyna-production \
  --force-sync \
  --update-solver-data \
  --update-parallel-tokens \
  --update-user-analytics

# Diagnose dashboard performance
vantage licenses dashboard-diagnostics lsdyna-production \
  --check-api-response-times \
  --check-database-performance \
  --check-cache-efficiency \
  --generate-performance-report

Monitoring and Alerting Issues​

# Test LS-DYNA monitoring configuration
vantage licenses test-monitoring lsdyna-production \
  --test-license-alerts \
  --test-solver-alerts \
  --test-parallel-token-alerts \
  --test-performance-alerts \
  --test-escalation-procedures

# Reset monitoring configuration
vantage licenses reset-monitoring lsdyna-production \
  --reset-thresholds \
  --reset-alert-channels \
  --reset-escalation-policies \
  --apply-default-config

# Validate alert delivery
vantage licenses test-alerts lsdyna-production \
  --send-test-alerts \
  --verify-delivery \
  --check-formatting \
  --validate-escalation

Advanced Troubleshooting​

Debug Mode and Logging​

# Enable debug logging for LSTC server
sudo -u lstc tee -a /opt/lstc/config/lstc.conf <<EOF
LOG_LEVEL debug
DEBUG_MODE true
TRACE_LICENSE_REQUESTS true
TRACE_PARALLEL_TOKENS true
TRACE_SOLVER_OPERATIONS true
EOF

# Restart server with debug logging
sudo systemctl restart lstc-server

# Monitor debug logs in real-time
tail -f /opt/lstc/logs/lstc_debug.log

# Enable LS-DYNA solver debugging
export LSTC_DEBUG=1
export LSDYNA_DEBUG=1
export OMP_DISPLAY_ENV=true

Performance Profiling​

import textwrap

def create_performance_profiler():
    """Create LS-DYNA performance profiling script."""
    
    profiler_script = textwrap.dedent("""
        #!/bin/bash
        # LS-DYNA Performance Profiling Script
        
        echo "=== LS-DYNA Performance Profiling ==="
        
        # Profile license acquisition time
        echo "Profiling license acquisition performance:"
        for solver in explicit implicit em thermal; do
            echo "  Testing $solver solver:"
            for i in {1..10}; do
                start=$(date +%s.%N)
                /opt/lstc/bin/lstc_qrun -checkout -solver "$solver" -ncpu 1 -s 31010@lstc-server.company.com >/dev/null 2>&1
                if [ $? -eq 0 ]; then
                    end=$(date +%s.%N)
                    duration=$(echo "$end - $start" | bc)
                    echo "    Attempt $i: ${duration}s"
                    /opt/lstc/bin/lstc_qrun -release -solver "$solver" -s 31010@lstc-server.company.com >/dev/null 2>&1
                else
                    echo "    Attempt $i: FAILED"
                fi
                sleep 0.5
            done
        done
        echo
        
        # Profile parallel token acquisition
        echo "Profiling parallel token acquisition:"
        for ncpu in 2 4 8 16; do
            echo "  Testing $ncpu CPUs:"
            start=$(date +%s.%N)
            /opt/lstc/bin/lstc_qrun -checkout -solver explicit -ncpu "$ncpu" -s 31010@lstc-server.company.com >/dev/null 2>&1
            if [ $? -eq 0 ]; then
                end=$(date +%s.%N)
                duration=$(echo "$end - $start" | bc)
                echo "    $ncpu CPUs: ${duration}s"
                /opt/lstc/bin/lstc_qrun -release -solver explicit -s 31010@lstc-server.company.com >/dev/null 2>&1
            else
                echo "    $ncpu CPUs: FAILED"
            fi
            sleep 1
        done
        echo
        
        # System performance during LS-DYNA operations
        echo "System performance baseline:"
        echo "  CPU usage: $(top -bn1 | grep "Cpu(s)" | awk '{print $2}' | cut -d'%' -f1)%"
        echo "  Memory usage: $(free | grep Mem | awk '{printf "%.1f%%", $3/$2 * 100.0}')"
        echo "  Network connections: $(netstat -an | grep :31010 | wc -l)"
        """).strip()
    
    return profiler_script

# Create performance profiling script
profiler = create_performance_profiler()
print("Performance profiling script ready")

Log Analysis Tools​

# Create comprehensive log analysis tool
sudo tee /opt/lstc/bin/analyze-logs.sh <<'EOF'
#!/bin/bash
# LSTC Log Analysis Tool

LOG_DIR="/opt/lstc/logs"
ANALYSIS_DIR="/opt/lstc/analysis"
mkdir -p "$ANALYSIS_DIR"

echo "=== LSTC Log Analysis Report ==="
echo "Generated: $(date)"
echo

# Analyze license requests
echo "License Request Analysis:"
grep -h "LICENSE_REQUEST" "$LOG_DIR"/*.log | \
  awk '{print $4}' | sort | uniq -c | sort -nr | head -10
echo

# Analyze solver usage
echo "Solver Usage Analysis:"
grep -h "SOLVER_CHECKOUT" "$LOG_DIR"/*.log | \
  awk '{print $5}' | sort | uniq -c | sort -nr
echo

# Analyze parallel token usage
echo "Parallel Token Usage Analysis:"
grep -h "PARALLEL_TOKEN" "$LOG_DIR"/*.log | \
  awk '{print $4, $6}' | sort | uniq -c | sort -nr | head -20
echo

# Find errors and warnings
echo "Recent Errors and Warnings:"
grep -h -E "(ERROR|WARNING)" "$LOG_DIR"/*.log | tail -20
echo

# Performance statistics
echo "Performance Statistics:"
grep -h "RESPONSE_TIME" "$LOG_DIR"/*.log | \
  awk '{sum+=$6; count++} END {printf "Average response time: %.3fs\n", sum/count}'

# Generate summary report
cat > "$ANALYSIS_DIR/summary-$(date +%Y%m%d).txt" <<SUMMARY
LSTC Log Analysis Summary - $(date)

Top License Requesters:
$(grep -h "LICENSE_REQUEST" "$LOG_DIR"/*.log | awk '{print $7}' | sort | uniq -c | sort -nr | head -5)

Top Solver Usage:
$(grep -h "SOLVER_CHECKOUT" "$LOG_DIR"/*.log | awk '{print $5}' | sort | uniq -c | sort -nr)

Error Count: $(grep -c "ERROR" "$LOG_DIR"/*.log)
Warning Count: $(grep -c "WARNING" "$LOG_DIR"/*.log)
SUMMARY

echo "Detailed analysis saved to: $ANALYSIS_DIR/summary-$(date +%Y%m%d).txt"
EOF

sudo chmod +x /opt/lstc/bin/analyze-logs.sh
sudo chown lstc:lstc /opt/lstc/bin/analyze-logs.sh

Escalation Procedures​

When to Contact Support​

LSTC Support Scenarios:

  • License file corruption or validation failures
  • Parallel token allocation issues beyond local configuration
  • Solver-specific compatibility problems
  • Performance issues that persist after optimization

Vantage Support Scenarios:

  • Dashboard connectivity or data synchronization issues
  • Integration problems with HPC clusters
  • Advanced monitoring and alerting configuration
  • API or CLI tool malfunctions

Collecting Diagnostic Information​

# Create comprehensive diagnostic collection script
sudo tee /opt/lstc/bin/collect-diagnostics.sh <<'EOF'
#!/bin/bash
# Comprehensive LS-DYNA Diagnostic Collection

DIAG_DIR="/tmp/lstc-diagnostics-$(date +%Y%m%d-%H%M%S)"
mkdir -p "$DIAG_DIR"

echo "Collecting LS-DYNA diagnostic information..."

# System information
uname -a > "$DIAG_DIR/system-info.txt"
cat /etc/os-release >> "$DIAG_DIR/system-info.txt"
free -h > "$DIAG_DIR/memory-info.txt"
df -h > "$DIAG_DIR/disk-info.txt"
lscpu > "$DIAG_DIR/cpu-info.txt"

# LSTC configuration
cp -r /opt/lstc/config "$DIAG_DIR/"
cp -r /opt/lstc/licenses "$DIAG_DIR/"

# Logs (last 1000 lines)
tail -1000 /opt/lstc/logs/*.log > "$DIAG_DIR/lstc-logs.txt" 2>/dev/null

# Network configuration
ip addr show > "$DIAG_DIR/network-config.txt"
netstat -tlnp | grep -E ":(31010|31011) " > "$DIAG_DIR/lstc-ports.txt"

# Current status
/opt/lstc/bin/lstc_qstat -s 31010@lstc-server.company.com > "$DIAG_DIR/lstc-status.txt" 2>&1
/opt/lstc/bin/lstc_qstat -t -s 31010@lstc-server.company.com > "$DIAG_DIR/parallel-tokens.txt" 2>&1

# Environment variables
env | grep -E "(LSTC|LSDYNA|OMP|MPI)" > "$DIAG_DIR/environment.txt"

# Create archive
tar -czf "/tmp/lstc-diagnostics-$(date +%Y%m%d-%H%M%S).tar.gz" -C "/tmp" "$(basename "$DIAG_DIR")"
rm -rf "$DIAG_DIR"

echo "Diagnostic information collected in: /tmp/lstc-diagnostics-$(date +%Y%m%d-%H%M%S).tar.gz"
EOF

sudo chmod +x /opt/lstc/bin/collect-diagnostics.sh

Emergency Procedures​

# Emergency LS-DYNA license service restoration
sudo tee /opt/lstc/bin/emergency-restore.sh <<'EOF'
#!/bin/bash
# Emergency LS-DYNA License Service Restoration

echo "=== EMERGENCY LS-DYNA LICENSE SERVICE RESTORATION ==="

# Stop all LSTC services
systemctl stop lstc-server
sleep 5

# Clear any stuck processes
pkill -f lstc_server
pkill -f lstc_qrun

# Clean temporary files
rm -f /tmp/lstc_*
rm -f /var/lock/lstc_*

# Reset license file permissions
chown -R lstc:lstc /opt/lstc/
chmod 644 /opt/lstc/licenses/*.lic
chmod 755 /opt/lstc/bin/*

# Restart with minimal configuration
systemctl start lstc-server

# Wait and test
sleep 30
if /opt/lstc/bin/lstc_qstat -s 31010@localhost >/dev/null 2>&1; then
    echo "Emergency restoration: SUCCESS"
    echo "LS-DYNA license service is operational"
else
    echo "Emergency restoration: FAILED"
    echo "Manual intervention required"
    exit 1
fi
EOF

sudo chmod +x /opt/lstc/bin/emergency-restore.sh

Best Practices​

Preventive Maintenance​

Regular Health Checks:

  • Schedule weekly license connectivity tests
  • Monitor parallel token utilization trends
  • Verify solver availability for all LS-DYNA variants
  • Check system resource usage and capacity planning

Configuration Management:

  • Maintain backup copies of working configurations
  • Version control for license files and server configurations
  • Document all customizations and optimizations
  • Test configuration changes in staging environment

Monitoring and Alerting:

  • Set up proactive monitoring for license expiration
  • Configure alerts for parallel token exhaustion
  • Monitor solver-specific performance metrics
  • Implement escalation procedures for critical issues

Documentation and Knowledge Management​

Troubleshooting Playbooks:

  • Create step-by-step procedures for common issues
  • Document environment-specific configurations
  • Maintain contact information for escalation
  • Regular review and update of troubleshooting procedures

Performance Baselines:

  • Establish performance benchmarks for license operations
  • Monitor trends in solver usage and performance
  • Regular capacity planning reviews
  • Optimization recommendations based on usage patterns

Next Steps​

Troubleshooting Best Practice: LS-DYNA troubleshooting requires understanding both the LSTC license server mechanics and the specific requirements of different LS-DYNA solvers (explicit, implicit, EM, thermal). Always start with basic connectivity tests and progress to solver-specific diagnostics. Parallel token issues are common in high-performance environments, so monitor token usage patterns closely. The Vantage License Manager provides comprehensive troubleshooting tools specifically designed for LS-DYNA environments, including solver-aware diagnostics and automated problem resolution.