infra-automation/cheatsheets/playbooks/gather_system_info.md

Gather System Info Playbook Cheatsheet

Quick reference for using the gather_system_info.yml playbook to collect comprehensive system information across infrastructure.

Quick Start

# Gather information from all hosts
ansible-playbook playbooks/gather_system_info.yml

# Specific environment
ansible-playbook -i inventories/production playbooks/gather_system_info.yml

# Specific host group
ansible-playbook playbooks/gather_system_info.yml --limit webservers

Common Usage

Basic Execution

# All hosts in inventory
ansible-playbook playbooks/gather_system_info.yml

# Single host
ansible-playbook playbooks/gather_system_info.yml --limit server01.example.com

# Specific group
ansible-playbook playbooks/gather_system_info.yml --limit databases

# Check mode (dry-run)
ansible-playbook playbooks/gather_system_info.yml --check

Selective Information Gathering

# CPU information only
ansible-playbook playbooks/gather_system_info.yml --tags cpu

# Memory and disk only
ansible-playbook playbooks/gather_system_info.yml --tags memory,disk

# Hypervisor detection only
ansible-playbook playbooks/gather_system_info.yml --tags hypervisor

# Skip installation of packages
ansible-playbook playbooks/gather_system_info.yml --skip-tags install

# Validation and health checks only
ansible-playbook playbooks/gather_system_info.yml --tags validate,health-check

Available Tags

Tag	Description
system_info	Main role tag (automatically included)
install	Install required packages
gather	All information gathering tasks
system	OS and system information
cpu	CPU details and capabilities
gpu	GPU detection and details
memory	RAM and swap information
disk	Storage, LVM, and RAID information
network	Network interfaces and configuration
hypervisor	Virtualization platform detection
export	Export statistics to JSON
statistics	Statistics aggregation
validate	Validation checks
health-check	System health monitoring
security	Security-related information

Playbook Variables

Variable	Default	Description
system_info_stats_base_dir	./stats/machines	Base directory for output
system_info_gather_cpu	true	Gather CPU information
system_info_gather_gpu	true	Gather GPU information
system_info_gather_memory	true	Gather memory information
system_info_gather_disk	true	Gather disk information
system_info_gather_network	true	Gather network information
system_info_detect_hypervisor	true	Detect hypervisor capabilities

Output Files

Default Location

./stats/machines/<fqdn>/
├── system_info.json           # Latest statistics
├── system_info_<epoch>.json   # Timestamped backup
└── summary.txt                 # Human-readable summary

View Statistics

# View JSON (pretty-printed)
jq . ./stats/machines/server01.example.com/system_info.json

# View human-readable summary
cat ./stats/machines/server01.example.com/summary.txt

# List all hosts with stats
ls -1 ./stats/machines/

# Count total hosts
ls -1d ./stats/machines/*/ | wc -l

Example Invocations

Basic Examples

# Production inventory
ansible-playbook -i inventories/production playbooks/gather_system_info.yml

# Staging inventory
ansible-playbook -i inventories/staging playbooks/gather_system_info.yml

# Custom output directory
ansible-playbook playbooks/gather_system_info.yml \
  -e "system_info_stats_base_dir=/var/lib/ansible/inventory"

Advanced Examples

# Hypervisors only with full gathering
ansible-playbook playbooks/gather_system_info.yml \
  --limit hypervisors \
  -e "system_info_detect_hypervisor=true"

# Quick scan (minimal gathering)
ansible-playbook playbooks/gather_system_info.yml \
  -e "system_info_gather_network=false" \
  -e "system_info_gather_gpu=false" \
  --skip-tags install

# Parallel execution (10 hosts at a time)
ansible-playbook playbooks/gather_system_info.yml -f 10

# With increased verbosity
ansible-playbook playbooks/gather_system_info.yml -v

Data Queries

Using jq for Data Extraction

# Get CPU models across all hosts
jq -r '.cpu.model' ./stats/machines/*/system_info.json

# Get memory usage
jq -r '"\(.host_info.fqdn): \(.memory.usage_percent)%"' \
  ./stats/machines/*/system_info.json

# Find hypervisors
jq -r 'select(.hypervisor.is_hypervisor == true) | .host_info.fqdn' \
  ./stats/machines/*/system_info.json

# Find virtual machines
jq -r 'select(.hypervisor.is_virtual == true) | .host_info.fqdn' \
  ./stats/machines/*/system_info.json

# Get OS distribution
jq -r '"\(.host_info.fqdn): \(.system.distribution) \(.system.distribution_version)"' \
  ./stats/machines/*/system_info.json

# Find hosts with high CPU count
jq -r 'select(.cpu.count.vcpus > 8) | "\(.host_info.fqdn): \(.cpu.count.vcpus) vCPUs"' \
  ./stats/machines/*/system_info.json

# Find hosts with low disk space
jq -r 'select(.disk.usage_percent > 80) | "\(.host_info.fqdn): \(.disk.usage_percent)%"' \
  ./stats/machines/*/system_info.json

Generate Reports

# CSV export: Hostname, OS, CPU, Memory
jq -r '["FQDN","OS","CPU Cores","Memory GB"],
       ([.host_info.fqdn, .system.distribution,
         .cpu.count.vcpus, (.memory.total_mb/1024|round)]) | @csv' \
  ./stats/machines/*/system_info.json > infrastructure_report.csv

# Count CPUs across infrastructure
jq -s 'map(.cpu.count.total_cores | tonumber) | add' \
  ./stats/machines/*/system_info.json

# Total memory across infrastructure (GB)
jq -s 'map(.memory.total_mb | tonumber) | add / 1024 | round' \
  ./stats/machines/*/system_info.json

# List GPU-enabled hosts
jq -r 'select(.gpu.detected == true) | "\(.host_info.fqdn): \(.gpu.devices[0].model)"' \
  ./stats/machines/*/system_info.json

# SELinux status report
jq -r '"\(.host_info.fqdn): SELinux \(.security.selinux)"' \
  ./stats/machines/*/system_info.json | grep -v "N/A"

# AppArmor status report
jq -r '"\(.host_info.fqdn): AppArmor \(.security.apparmor)"' \
  ./stats/machines/*/system_info.json | grep -v "N/A"

Integration Examples

Cron Job for Regular Collection

# Daily collection at 2 AM
0 2 * * * cd /opt/ansible && ansible-playbook playbooks/gather_system_info.yml \
  >> /var/log/ansible/gather_system_info.log 2>&1

SystemD Timer

# /etc/systemd/system/ansible-gather-system-info.timer
[Unit]
Description=Gather System Information Daily

[Timer]
OnCalendar=daily
Persistent=true

[Install]
WantedBy=timers.target

# /etc/systemd/system/ansible-gather-system-info.service
[Unit]
Description=Ansible Gather System Information

[Service]
Type=oneshot
WorkingDirectory=/opt/ansible
ExecStart=/usr/bin/ansible-playbook playbooks/gather_system_info.yml
User=ansible
StandardOutput=append:/var/log/ansible/gather_system_info.log
StandardError=append:/var/log/ansible/gather_system_info.log

CMDB Integration

# Export to NetBox or other CMDB
for host_dir in ./stats/machines/*/; do
  host=$(basename "$host_dir")
  curl -X POST https://netbox.example.com/api/dcim/devices/ \
    -H "Authorization: Token $NETBOX_TOKEN" \
    -H "Content-Type: application/json" \
    -d @"${host_dir}/system_info.json"
done

Monitoring Integration

# Create Prometheus metrics
for stats_file in ./stats/machines/*/system_info.json; do
  host=$(jq -r '.host_info.fqdn' "$stats_file")
  cpu=$(jq -r '.cpu.count.vcpus' "$stats_file")
  mem=$(jq -r '.memory.total_mb' "$stats_file")

  cat <<EOF > /var/lib/node_exporter/textfile_collector/${host}.prom
# HELP system_info_cpu_count Number of CPU cores
# TYPE system_info_cpu_count gauge
system_info_cpu_count{host="$host"} $cpu

# HELP system_info_memory_mb Total memory in MB
# TYPE system_info_memory_mb gauge
system_info_memory_mb{host="$host"} $mem
EOF
done

Troubleshooting

Check Playbook Execution

# Dry-run (check mode)
ansible-playbook playbooks/gather_system_info.yml --check

# Verbose output
ansible-playbook playbooks/gather_system_info.yml -v

# Very verbose (debug)
ansible-playbook playbooks/gather_system_info.yml -vvv

# Single host debugging
ansible-playbook playbooks/gather_system_info.yml \
  --limit problematic-host -vvv

Common Issues

Missing packages

# Install packages manually first
ansible all -m package -a "name=lshw,dmidecode,pciutils state=present" --become

# Or run with install tag only
ansible-playbook playbooks/gather_system_info.yml --tags install

Permission errors

# Ensure become is enabled
ansible-playbook playbooks/gather_system_info.yml --become

# Check sudo access
ansible all -m ping --become

Statistics not saved

# Check if directory exists
ls -la ./stats/machines/

# Check disk space
df -h .

# Create directory manually
mkdir -p ./stats/machines

# Specify alternative directory
ansible-playbook playbooks/gather_system_info.yml \
  -e "system_info_stats_base_dir=/tmp/stats"

Slow execution

# Skip slow operations
ansible-playbook playbooks/gather_system_info.yml \
  --skip-tags install,network

# Disable GPU gathering
ansible-playbook playbooks/gather_system_info.yml \
  -e "system_info_gather_gpu=false"

# Increase parallelism
ansible-playbook playbooks/gather_system_info.yml -f 20

Validation

# Verify JSON files are valid
for f in ./stats/machines/*/system_info.json; do
  echo "Checking $f"
  jq empty "$f" && echo "✓ OK" || echo "✗ INVALID"
done

# Check for missing files
for host in $(ansible all --list-hosts | tail -n +2); do
  if [ ! -f "./stats/machines/${host}/system_info.json" ]; then
    echo "Missing: $host"
  fi
done

# Verify data completeness
jq -r 'if .cpu == null then "Missing CPU data" else "OK" end' \
  ./stats/machines/*/system_info.json

Performance Optimization

Parallel Execution

# Default (5 hosts at a time)
ansible-playbook playbooks/gather_system_info.yml

# Increase parallelism
ansible-playbook playbooks/gather_system_info.yml -f 20

# Serial execution (one at a time)
ansible-playbook playbooks/gather_system_info.yml -f 1

Skip Slow Tasks

# Skip package installation
ansible-playbook playbooks/gather_system_info.yml --skip-tags install

# Skip network gathering
ansible-playbook playbooks/gather_system_info.yml --skip-tags network

# Minimal gathering
ansible-playbook playbooks/gather_system_info.yml \
  -e "system_info_gather_gpu=false" \
  -e "system_info_gather_network=false" \
  -e "system_info_detect_hypervisor=false"

Fact Caching

Enable in ansible.cfg:

[defaults]
fact_caching = jsonfile
fact_caching_connection = /tmp/ansible_facts
fact_caching_timeout = 3600

Use Cases

Infrastructure Audit

# Collect from all environments
for env in production staging development; do
  ansible-playbook -i inventories/$env playbooks/gather_system_info.yml
done

# Generate comprehensive report
./scripts/generate_infrastructure_report.sh

Capacity Planning

# Gather current utilization
ansible-playbook playbooks/gather_system_info.yml --tags validate,health-check

# Analyze resource usage
jq -r '"\(.host_info.fqdn),\(.cpu.load_average.one_min),\(.memory.usage_percent),\(.disk.usage_percent)"' \
  ./stats/machines/*/system_info.json | column -t -s,

Compliance Reporting

# Security compliance check
ansible-playbook playbooks/gather_system_info.yml --tags security

# Generate compliance report
jq -r '"\(.host_info.fqdn),\(.security.selinux),\(.security.apparmor)"' \
  ./stats/machines/*/system_info.json > compliance_report.csv

License Auditing

# Count CPU cores for licensing
ansible-playbook playbooks/gather_system_info.yml --tags cpu

# Total cores
jq -s 'map(.cpu.count.total_cores | tonumber) | add' \
  ./stats/machines/*/system_info.json

Quick Reference Commands

# Standard execution
ansible-playbook playbooks/gather_system_info.yml

# Specific hosts
ansible-playbook playbooks/gather_system_info.yml --limit webservers

# Specific tags
ansible-playbook playbooks/gather_system_info.yml --tags cpu,memory

# Custom output directory
ansible-playbook playbooks/gather_system_info.yml \
  -e "system_info_stats_base_dir=/custom/path"

# View latest stats
cat ./stats/machines/$(hostname -f)/summary.txt

# Query all hosts
jq . ./stats/machines/*/system_info.json | less

See Also

• System Info Role README
• System Info Role Documentation
• System Info Role Cheatsheet
• Role Index

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Playbook: gather_system_info.yml Updated: 2025-11-11 Related Role: system_info v1.0.0