Slack

dockmesh alerts can fire into any Slack channel via an incoming webhook.

Create a Slack webhook

In Slack, go to Apps → Incoming Webhooks → Add to Slack
Choose the channel (e.g. #ops-alerts)
Click Add Incoming Webhook Integration
Copy the webhook URL — looks like https://hooks.slack.com/services/T.../B.../xxxx

Add to dockmesh

Alerts → Channels → New channel → Slack

Field	Value
Name	`ops-alerts`
Webhook URL	paste the URL from Slack

Click Send test — a test message should appear in Slack within 2 seconds.

Attach to alert rules

Open the rule under Alerts → Rules, edit it, and add the Slack channel to its Channels list. Severity filtering happens per rule, not per channel — there is no global “Slack gets all, PagerDuty gets only critical” toggle. Express the same intent by listing Slack on every rule and PagerDuty only on critical-severity rules.

Message format

Alerts fire with a payload like:

🔴 [Critical] Container memory > 90% (sustained)
Container: paperless-gotenberg-1 on local
Metric: mem_percent  value: 93.4  threshold: 90
Rule: Container memory > 90% (sustained)

→ View in dockmesh

The metric is one of cpu_percent or mem_percent — those are the two the alert engine evaluates today. The link points back at the alert detail in dockmesh.

Thread replies for resolution

When an alert auto-resolves (metric returns below threshold), dockmesh replies in the same Slack thread:

✓ Resolved after 4m12s — metric returned to normal

Easy to see in-channel which alerts are still active.

Slack App (for larger setups)

For orgs on Slack Enterprise Grid, or if you want OAuth-scoped access instead of webhooks:

Create a Slack app at api.slack.com/apps
Enable OAuth & Permissions with scopes: chat:write, chat:write.customize
Install to workspace, get the Bot User OAuth Token
In dockmesh, switch the channel type from Webhook to Bot Token
Choose which channels the bot can post to

Bot-token channels support richer formatting (buttons, attachments) and don’t expire.

Troubleshooting

No messages arriving:

Send test from dockmesh — does it succeed?
Check the Slack channel’s “Integration logs” to see if the webhook received anything
If the webhook URL was regenerated in Slack, update it in dockmesh

Rate limits:

Slack limits webhooks to ~1 msg/sec per channel. If your alert storm exceeds that, dockmesh queues and retries with backoff
For high-volume alerting, create multiple channels (e.g. per-service) instead of one firehose