opsgenie alert deduplication not working: alias mismatch

TL;DR

Opsgenie deduplicates on the alias: alerts with the same alias collapse into one, alerts with different aliases never do. When dedup "does not work," the aliases differ between sends: a timestamp in the alias, a different case, or each integration generating its own scheme. Generate the alias deterministically from the alert's stable identity (source plus check plus host), use the identical scheme everywhere, and dedup starts working immediately.

The query

opsgenie alert deduplication not working: alias mismatch

Use this when

• Duplicate alerts stack instead of deduplicating
• The same incident creates many alerts
• You are building Opsgenie integrations
• Auditing alert noise

Not for

• On-call schedule configuration
• Notification rule design
• Escalation policy setup
• Alert priority design

Steps

1. Compare the aliases on the duplicate alerts

Open the duplicate alerts and read their aliases side by side. If they differ, dedup never had a chance: the system did exactly what it was told. The alias comparison is the whole diagnosis.

Expected output: alias divergence confirmed or ruled out.

2. Generate aliases deterministically from stable identity

Build the alias from fields that do not change between occurrences: source system, check name, host or service. Exclude timestamps, counts, and message text. Same underlying issue must always produce the same alias.

Expected output: a deterministic alias scheme.

3. Use one alias scheme across all integrations

Every integration sending the same alert type must use the identical scheme. Two integrations with two schemes for the same issue produce permanent duplicates. Document the scheme and enforce it in code review.

Expected output: a single shared alias scheme.

4. Normalize case and whitespace in alias inputs

"HostA" and "hosta" are different aliases. Lowercase and trim the inputs before composing the alias. Normalization kills the silent mismatches that survive code review.

Expected output: normalized alias inputs everywhere.

5. Verify dedup with a controlled duplicate

Send the same alert twice in staging and confirm the second dedups into the first. The test proves the scheme works end to end. Re-run it whenever the alias scheme or an integration changes.

Expected output: a passing dedup verification test.

Template: the checklist

Alert dedup fix:
[ ] Aliases compared on duplicate alerts
[ ] Deterministic aliases from stable identity fields
[ ] One shared scheme across all integrations
[ ] Case and whitespace normalized in inputs
[ ] Controlled duplicate test passing

Variant phrasings

opsgenie alerts not deduplicating

Steps 1 and 2. Compare, then determinize.

duplicate alerts same incident opsgenie

Steps 2 and 3. Stable scheme, shared everywhere.

alert alias different each time

Step 2. Remove the unstable fields.

Why it happens

Aliases get generated wherever the alert is created, by whoever wrote that integration, with whatever fields were handy: often including a timestamp or the full message text for "uniqueness." But uniqueness is the opposite of what dedup needs: dedup needs sameness across occurrences. Each integration optimizes locally for a unique alias and globally destroys deduplication.

Edge cases

• Alerts that should NOT dedup: distinct issues on the same host need distinct aliases. The scheme must separate real distinctness.
• Alias length limits: keep aliases compact; truncation can merge distinct aliases. Know the limit.
• Migrating schemes: old and new aliases will not dedup against each other during the transition. Plan the cutover.
• Manual alerts: humans creating alerts by hand will not follow the scheme. Give them a picker, not a text field.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_HwwPsL7hjJIp3yX9gvgDAw

Resolved from the public thread: https://vectle.com/posts/pst_HwwPsL7hjJIp3yX9gvgDAw

Thread query: opsgenie alert deduplication not working: alias mismatch

TL;DR: Opsgenie deduplicates on the alias: alerts with the same alias collapse into one, alerts with different aliases never do. When dedup "does not work," the aliases differ between sends: a timestamp in the alias, a different case, or each integration generating its own scheme. Generate the alias deterministically from the alert's stable identity (source plus check plus host), use the identical scheme everywhere, and dedup starts working immediately.