OpenNHP/opennhp · error

clock_gettime failed

Error message

clock_gettime failed: %v

What it means

getBootTimeNanos reads CLOCK_BOOTTIME via unix.ClockGettime to compute monotonic boot time used for eBPF ktime translation. If the raw syscall fails (returns non-nil errno), the error is wrapped as 'clock_gettime failed'. This indicates the kernel refused or could not service the clock query.

Solutions

1. Check kernel support: CLOCK_BOOTTIME exists since Linux 2.6.39 — upgrade if ancient
2. Inspect seccomp/container profile and allow clock_gettime / clock id 7 (CLOCK_BOOTTIME)
3. Fall back to CLOCK_MONOTONIC if boot-time offset is not required
4. Confirm the binary is running on Linux as intended

Example fix

// before
if err := unix.ClockGettime(unix.CLOCK_BOOTTIME, &ts); err != nil { return 0, fmt.Errorf("clock_gettime failed: %v", err) }
// after
if err := unix.ClockGettime(unix.CLOCK_BOOTTIME, &ts); err != nil {
    if err2 := unix.ClockGettime(unix.CLOCK_MONOTONIC, &ts); err2 != nil {
        return 0, fmt.Errorf("clock_gettime failed: %v", err)
    }
}

// runtime check before enabling eBPF
if runtime.GOOS != "linux" { skipEbpf() }

bt, err := getBootTimeNanos(); if err != nil { log.Warn("ktime unavailable: %v", err); bt = fallbackMonotonic() }

When it happens

Trigger: unix.ClockGettime(unix.CLOCK_BOOTTIME, &ts) returns an error — typically on kernels/seccomp profiles that filter clock syscalls, sandboxes blocking CLOCK_BOOTTIME, or (on the !linux build) stub environments.

Common situations: Running inside restricted containers/gVisor/seccomp sandboxes that whitelist only CLOCK_REALTIME/MONOTONIC; porting code to a non-Linux platform where the linux-tagged file is compiled inadvertently; ancient kernels lacking CLOCK_BOOTTIME.

Understand the failure class

Background: "unsupported platform" / "not supported on this platform" errors: what they mean and how to fix them — this error's family across 47 libraries.

Related errors

• Failed to get the system running time:
• eBPF functionality is only supported on Linux, current…
• failed to parse default route
• eBPF functionality is only supported on Linux, current…
• 'events' map not found

AI-assisted analysis of OpenNHP/opennhp@6e04ca5ff0 (2026-09-07). Data as JSON: /api/errors/c3c62f3040de2b17. Report an issue: GitHub.

Appendix: source

Thrown at nhp/utils/ebpf/ebpf_linux.go:14

//go:build linux

package ebpf

import (
	"fmt"

	"golang.org/x/sys/unix"
)

func getBootTimeNanos() (uint64, error) {
	var ts unix.Timespec
	if err := unix.ClockGettime(unix.CLOCK_BOOTTIME, &ts); err != nil {
		return 0, fmt.Errorf("clock_gettime failed: %v", err)
	}
	return uint64(ts.Sec)*1e9 + uint64(ts.Nsec), nil
}

View on GitHub (pinned to 6e04ca5ff0)