Missed attestation alerts that aren't noise
The problem with most missed-attestation alerts: they fire on every single miss. Isolated timing misses, single missed heads, peering hiccups — your phone buzzes, you start ignoring it, you miss the one that matters.
What Eyrium does differently: configurable streak threshold (1–10 consecutive misses before alert fires) plus head-only-miss suppression (filter out the misses where only the head vote was missed but target + source landed).
Cost: Pro ($7/mo) — needs Telegram or native push to deliver in real-time. Free tier gets email-only.
What is a missed attestation?
Every Ethereum validator is expected to make an attestation once per epoch (~6.4 minutes). An attestation is a vote on three things: the head of the chain, the target checkpoint, and the source checkpoint. Each component earns a separate reward.
A "missed attestation" is when one or more of those three votes don't get included on-chain within the inclusion window. The lost reward per individual miss is small in ETH terms — the exact amount depends on your effective balance and on which components were missed — but a sustained miss rate warrants investigation. Eyrium records the actual and ideal reward for each component, so the gap is measured rather than estimated.
Why missed attestations happen
Common causes:
- Block propagation timing. Your validator signed the attestation, but the head block reached it late, or the attestation was included later than the one-slot window head requires. This shows up as a head-only miss: target and source landed, head did not.
- Peering issues. Your node lost connectivity to enough peers to either not see the head in time or not propagate your attestation in time.
- Hardware / I/O lag. Disk pressure, swap, network card under load. Validator client logs are slow because the machine is busy.
- Client crash or restart. Validator client was down for the slot.
- Chain reorgs. Less common, but reorgs can orphan attestations that were technically on-time.
Notice what's not on this list: "you got hacked," "you're about to be slashed," or "you need to panic." Single missed attestations are the chain equivalent of a packet drop. They happen. The signal is in the rate.
The noise problem
Tools that alert on every missed attestation can produce high alert volume, because head-only misses can occur on healthy validators. Operators may mute the notifications, and then miss the real problem when it arrives.
The fix is filtering. Don't alert on noise.
How Eyrium's missed-attestation alerts work
Eyrium gives you two configurable filters that, used together, can reduce alert volume without discarding any history.
Filter 1: Streak threshold (min_streak)
- Integer, 1–10
- Default: 1 (fires on every miss — raise it to suppress isolated misses; the right value depends on your validator's own history)
- Configured per user (applies to every validator on your account, not per-validator)
- Configurable via Settings → Alert preferences → Missed attestation row → slider
- A streak threshold of 3 means: only fire an alert after your validator misses 3 consecutive attestations. Isolated misses get logged but don't notify.
Filter 2: Head-only-miss suppression (ignore_head_only_misses)
- Boolean, default
false - When
true, suppresses misses where only the head vote was missed but target + source landed - Head-only misses can reflect block propagation or inclusion timing rather than validator health — though a persistent run of them is still worth investigating
Used together — for example min_streak: 3, ignore_head_only_misses: true — these can reduce alert volume. Treat it as a starting point, not a recommendation: check your own miss history and adjust. Both settings currently apply to every validator on the account; per-validator control is not yet available.
Per-alert payload includes:
- The epoch the miss occurred in
head_reward,target_reward,source_reward— what you actually earnedideal_head_reward,ideal_target_reward,ideal_source_reward— what you would have earned with a perfect attestation- The gwei delta — exactly how much income was lost
When the Beacon API returns ideal rewards for the epoch, the alert carries the gwei loss so you can make an informed call about whether to investigate. When it doesn't, Eyrium records the actual components without a computed difference rather than substituting an estimate.
How it compares
| Eyrium | beaconcha.in | Rated Network | |
|---|---|---|---|
| Missed-attestation alert | ✓ | ✓ | ✗ (not a documented alerts product) |
| Configurable streak threshold | ✓ (1–10) | ✗ (no streak setting visible in their docs) | n/a |
| Head-only-miss suppression | ✓ | ✗ | n/a |
| Per-component reward breakdown in alert | ✓ | Partial | n/a |
| Channels | Email, Telegram, iOS/Android push | Email, webhook, push | n/a |
What to do if you're getting too many missed-attestation alerts
If your validator is genuinely missing attestations frequently — say, more than ~2% of attestations over a sustained period — work through this:
1. Check your client logs first. Most missed attestations have a clear cause in the validator or beacon client logs at the time of the miss. Don't guess; look.
2. Verify your peer count. Below ~30-50 peers on the beacon chain, attestation propagation degrades. Check what your client reports and compare against its target.
3. Check disk I/O. Validator clients are sensitive to disk latency. iostat or your platform's equivalent — if you see sustained high IOPS or queue depth, that's likely the cause.
4. Look at the time-of-day pattern. If misses cluster around backup jobs, log rotation, or other cron tasks, you've found it. Move the offending job, increase machine resources, or use I/O priority.
5. Update your validator client. Performance regressions and bug fixes ship constantly. If you're more than a minor version behind, upgrade.
If none of these change the rate, your hardware may be undersized for the validator count it's running.
FAQ
- How do I stop missed-attestation alerts from being noisy?
- Enable head-only-miss suppression and raise the streak threshold above 1. There is no single correct threshold — review your own validator's miss history and tune from there. The head-only filter suppresses only head-only notifications; the streak filter waits for consecutive real misses, so an isolated target or source miss can also be held back at a higher threshold. Both controls currently apply account-wide rather than per-validator. Every miss stays in your history and API regardless.
- Does the streak threshold apply per-validator or globally?
- Globally — it applies to every validator on your account. The same is true for head-only-miss suppression.
- What's a head-only miss?
- A missed attestation where only the head vote didn't make it on-chain in the inclusion window, but the target and source votes did. Head has the strictest timeliness requirement — it must be included at the minimum delay of one slot — so slow block propagation or a short reorg can cost head while target and source still land. Head carries less weight than target in the reward formula. Repeated head-only misses can still indicate local latency, peering, or clock problems, so a persistent pattern is worth investigating.
- Will I miss real issues if I set a high streak threshold?
- A validator-side problem — node down, client crashed, network unreachable — can produce consecutive misses rather than isolated ones, which is what the streak threshold is for. Isolated head-only misses can occur on healthy validators. Neither pattern is proof on its own; check your own history.
- Do I get missed-attestation alerts on the free tier?
- Yes, but only via email and only for your 1 validator on free tier. To monitor more validators or to get Telegram and native push delivery, you need Pro ($7/mo).
- What's in the alert payload?
- The epoch, your actual head/target/source rewards, the ideal head/target/source rewards (what a perfect attestation would have earned), and the gwei delta — exactly what the miss cost you.
- Does Eyrium alert on missed proposals or sync-committee misses?
- Yes. Every proposer duty is checked and an empty assigned slot fires an alert. Sync-committee assignments are tracked and missed signatures also alert. We also fire on missed attestations, balance drops, status changes (slashing, exit, withdrawal), and credentials changes.
Fewer interruptions, same record.
Set a streak threshold, enable head-only-miss suppression, and decide for yourself which misses are worth an interruption. Pro is $7/mo with Telegram and native mobile push.
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