Operating system information
Print operating system details without changes.
cat /etc/os-releaseSCRIPTS / RUNBOOKS
Practical diagnostic commands.
Small, read-only Bash and PowerShell snippets for common operations checks. Review and adapt them before running on an authorized system; this site does not execute any of these commands.
✳ Copy only; no remote command execution, uploads or account required.
FIELD REFERENCE
Browse interactive tools ↗Linux and Windows troubleshooting
Use these as starting points, not as a substitute for approved operational procedures. Commands involving example.com contact that hostname only when you run them.
Commands are shown for review. No command is run by this page.
Listening TCP / UDP ports
Inspect listening sockets and process IDs (permissions may limit process visibility).
ss -lntupFailed systemd units
See failed service units without restarting anything.
systemctl --failed --no-pagerRecent Apache service logs
Review recent Apache logs; change the unit name for other services.
journalctl -u apache2 --since '-30 minutes' --no-pagerDisk space and inodes
Check filesystem capacity and inode exhaustion.
df -hT && df -iDNS A record response
Look up an example DNS record; replace the hostname before running.
dig example.com A +noall +answerTLS handshake summary
Inspect a remote TLS endpoint that you are authorized to query.
openssl s_client -connect example.com:443 -servername example.com -brief </dev/nullNetwork adapter configuration
Inspect local DNS, gateways and assigned IP addresses.
Get-NetIPConfiguration | Format-ListDNS A record response
Resolve a domain from the local host's DNS configuration.
Resolve-DnsName example.com -Type ATCP connectivity test
Test a single authorized hostname and port; not a scan.
Test-NetConnection example.com -Port 443Recent critical system events
Read recent Windows System error events.
Get-WinEvent -FilterHashtable @{LogName='System'; Level=2; StartTime=(Get-Date).AddHours(-24)} -MaxEvents 30Local listening TCP sockets
List listening TCP ports and their associated process IDs.
Get-NetTCPConnection -State Listen | Select-Object LocalAddress, LocalPort, OwningProcessServices not running
List stopped services for inspection, not as proof that they are broken.
Get-Service | Where-Object Status -eq 'Stopped' | Select-Object Name, DisplayNameUse with care
These examples are intentionally non-destructive. Review shell quoting, operating system versions, network egress policy, and any command before execution. Do not paste access tokens, secrets, customer data or confidential logs into external sites.
RELATED READING
Technical Field Guide
Step-by-step explanations for DNS, incident response, Apache, PostgreSQL, Prometheus and safe deployments. Use the companion tools and scripts when a reference alone is not enough.
Read the 12 guides ↗DOWNLOADABLE RUNBOOKS
Browse the Query Library ↗Ready-to-review operations scripts.
Six small, transparent scripts and query files. Review their contents and your organization’s policies before execution. No automated repairs, deletions, or service restarts.
Linux Host Health
Disk capacity, inode counts, memory, load and failed systemd units.
Download source ↗Apache / PHP-FPM Troubleshooting
Configuration test, service states, origin health and PHP execution.
Download source ↗Docker Container Summary
Container status and space utilization without exposing environment variables.
Download source ↗Targeted DNS and HTTPS
DNS answers and one bounded HTTPS HEAD request for an authorized hostname.
Download source ↗PostgreSQL Health Queries
Read-only monitoring views for sessions, databases, locks and replication senders.
Download source ↗Windows System Health
OS, network configuration, service and recent Windows event summaries.
Download source ↗The network diagnostic makes a limited outbound request only when you run it with an authorized target. Some diagnostics can reveal system identifiers. Never run unreviewed scripts on production or share unsanitized outputs.