Files
git.stella-ops.org/docs/doctor/articles/timestamping/system-time-sync.md
master c58a236d70 Doctor plugin checks: implement health check classes and documentation
Implement remediation-aware health checks across all Doctor plugin modules
(Agent, Attestor, Auth, BinaryAnalysis, Compliance, Crypto, Environment,
EvidenceLocker, Notify, Observability, Operations, Policy, Postgres, Release,
Scanner, Storage, Vex) and their backing library counterparts (AI, Attestation,
Authority, Core, Cryptography, Database, Docker, Integration, Notify,
Observability, Security, ServiceGraph, Sources, Verification).

Each check now emits structured remediation metadata (severity, category,
runbook links, and fix suggestions) consumed by the Doctor dashboard
remediation panel.

Also adds:
- docs/doctor/articles/ knowledge base for check explanations
- Advisory AI search seed and allowlist updates for doctor content
- Sprint plan for doctor checks documentation

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-03-27 12:28:00 +02:00

2.1 KiB

checkId, plugin, severity, tags
checkId plugin severity tags
check.timestamp.timesync.system stellaops.doctor.timestamping fail
timestamping
timesync
ntp
system

System Time Synchronization

What It Checks

Checks that the system clock is synchronized with NTP servers. The check:

  • Queries configured NTP servers (defaults to time.nist.gov and pool.ntp.org) using the NTP protocol (UDP port 123).
  • Computes the time skew between the local system clock and each NTP server.
  • Fails (unhealthy) if skew exceeds the critical threshold (default 5 seconds).
  • Warns (degraded) if skew exceeds the warning threshold (default 1 second).
  • Reports degraded if no NTP servers can be reached.

Why It Matters

Accurate system time is fundamental to timestamping. Clock skew causes timestamp tokens to have incorrect genTime values, which can invalidate evidence during verification. Large skew can also cause TLS certificate validation failures, authentication token rejection, and incorrect audit log ordering.

Common Causes

  • NTP service not running (chrony, ntpd, systemd-timesyncd)
  • NTP servers unreachable (firewall blocking UDP 123)
  • Virtual machine time drift (especially paused/resumed VMs)
  • Hardware clock issues

How to Fix

Docker Compose

Docker containers inherit the host's clock. Fix time sync on the Docker host:

# Check host time sync
timedatectl status

# Enable NTP sync
sudo timedatectl set-ntp true

# Or configure chrony
sudo systemctl restart chronyd

Bare Metal / systemd

# Check time sync status
timedatectl status
chronyc tracking

# Force sync
sudo chronyc makestep

# Enable NTP
sudo timedatectl set-ntp true
sudo systemctl enable chronyd

Kubernetes / Helm

Kubernetes nodes must have NTP configured. Verify on each node:

# On each node
timedatectl status
chronyc tracking

Ensure NTP is part of your node provisioning configuration.

Verification

stella doctor run --check check.timestamp.timesync.system
  • check.timestamp.timesync.tsa-skew — checks skew between system clock and TSA genTime
  • check.timestamp.timesync.rekor-correlation — checks TST-Rekor time correlation