How to Check System Library Dependencies

How to Check System Library Dependencies

Need to check system library dependencies on your Linux server? Want to monitor library dependencies, verify library availability, and detect missing libraries? This guide shows you how to check library dependencies using built-in commands and automated monitoring with Zuzia.app.

For comprehensive system monitoring strategies, see Server Performance Monitoring Best Practices. For troubleshooting dependency issues, see System Updates Breaking Services.

Why Checking Library Dependencies Matters

System libraries provide shared functionality for applications. When library dependencies are missing or incompatible, applications can fail to start, services can crash, and system functionality can be compromised. Checking library dependencies helps you verify libraries are available, detect missing dependencies, track library versions, and maintain system stability.

Method 1: Check Library Dependencies

Check library dependencies to verify libraries are available:

View Library Dependencies

# Check library dependencies for binary
ldd /usr/bin/application

# View missing libraries
ldd /usr/bin/application | grep "not found"

# Check library dependencies for process
ldd /proc/PID/exe

# View all library dependencies
ldd /usr/bin/* | grep "not found"

Verify Library Availability

# Check if library exists
test -f /usr/lib/libssl.so && echo "Library exists" || echo "Library missing"

# View library search paths
ldconfig -p

# Check library versions
ldconfig -p | grep libssl

# Verify library compatibility
ldd /usr/bin/application | grep -v "not found"

Method 2: Detect Missing Libraries

Detect missing libraries to identify dependency issues:

Identify Missing Dependencies

# Find binaries with missing libraries
for binary in /usr/bin/*; do
  ldd "$binary" 2>/dev/null | grep "not found" && echo "$binary: Missing libraries"
done

# Check for missing shared libraries
ldd /usr/bin/application | grep "not found"

# View library dependency errors
ldconfig -p 2>&1 | grep -i "error\|fail"

# Check library loading issues
dmesg | grep -i "library\|shared object"

Monitor Library Status

# Check library cache
ldconfig -p | wc -l

# View library cache status
ldconfig -v 2>&1 | tail -20

# Check for library conflicts
ldconfig -p | grep libssl | wc -l

# Verify library paths
echo $LD_LIBRARY_PATH

Method 3: Monitor Library Updates

Monitor library updates to track library changes:

Track Library Versions

# View library versions
ldconfig -p | grep libssl

# Check library modification times
find /usr/lib -name "*.so*" -mtime -1 -ls

# View library update history
grep "lib" /var/log/apt/history.log | tail -10

# Monitor library changes
ls -lt /usr/lib/*.so* | head -10

Detect Library Issues

# Check for library update errors
grep -i "library\|lib" /var/log/apt/history.log | grep -i "error\|fail"

# View library compatibility issues
ldd /usr/bin/application | grep -E "not found|version"

# Check library dependency conflicts
ldconfig -p | awk '{print $1}' | sort | uniq -d

Method 4: Automated Library Dependency Monitoring with Zuzia.app

While manual library dependency checks work for troubleshooting, production Linux servers require automated library dependency monitoring that continuously tracks library availability, detects missing dependencies, and alerts you when library issues occur.

How Zuzia.app Library Dependency Monitoring Works

Zuzia.app automatically monitors library dependencies through scheduled command execution. The platform checks library availability, verifies library dependencies, detects missing libraries, and sends alerts when library issues are detected.

Setting Up Library Dependency Monitoring

1. Add Scheduled Task for Library Checking

   • Command: ldd /usr/bin/application | grep -c "not found"
   • Frequency: Every 12 hours
   • Alert when: Missing libraries detected

2. Configure Library Availability Verification

   • Command: test -f /usr/lib/libssl.so && echo "OK" || echo "MISSING"
   • Frequency: Every 12 hours
   • Alert when: Critical libraries missing

3. Set Up Library Cache Monitoring

   • Command: ldconfig -p | wc -l
   • Frequency: Once daily
   • Alert when: Library cache issues detected

Custom Library Dependency Monitoring Commands

Add these commands as scheduled tasks:

# Check library dependencies
ldd /usr/bin/application | grep -v "not found"

# Verify library availability
ldconfig -p | grep libssl

# Detect missing libraries
ldd /usr/bin/application | grep "not found"

# Monitor library cache
ldconfig -p | wc -l

Best Practices

1. Monitor Library Dependencies Regularly

Check library dependencies every 12 hours. Use Zuzia.app for automated library monitoring. Verify library availability after updates.

2. Detect Missing Libraries

Identify missing libraries immediately. Track library dependencies. Fix library issues promptly.

3. Track Library Updates

Monitor library updates. Track library versions. Verify library compatibility after updates.

Troubleshooting

Missing Libraries Detected

When missing libraries are detected:

1. Check library dependencies: ldd /usr/bin/application
2. Identify missing libraries: ldd /usr/bin/application | grep "not found"
3. Install missing libraries: apt install library-name
4. Verify libraries installed: ldd /usr/bin/application

Library Dependency Issues

When library dependency issues occur:

1. Check library cache: ldconfig -p
2. Update library cache: ldconfig
3. Verify library paths: echo $LD_LIBRARY_PATH
4. Test library loading: ldd /usr/bin/application

FAQ

Related guides, recipes, and problems

• Related guides

  • Server Performance Monitoring Best Practices
  • System Updates and Package Management Monitoring Guide

• Related recipes

  • Monitor System Package Updates Available
  • Check Service Dependency Health

• Related problems

  • System Updates Breaking Services
  • Application Deployment Failures