Create a key to copy examples filled with your team.

Email bounces

Hard bounces suppress the address. Events stay on the cluster.

Kumo bounce types land as bounce on the cluster. Open the event list on that cluster, or subscribe to bounce on a delivery webhook.

What maps to bounce

Kumo type Webhook event
Bounce bounce
OOB bounce
AdminBounce bounce
Expiration bounce

A hard bounce adds a suppression with reason bounce. A spamreport (Kumo Feedback) adds one with reason spamreport. The next send to that address on that team and tenant returns 403 {error: suppressed}.

Hard bounce

PostShiba treats userunknown, hostunknown, and hasmoved as hard, plus an explicit hard or hardbounce flag on the log. Soft failures stay events. They do not add a row.

MAIL FROM is rewritten to {id}@rp.your-domain so DSN and ARF come back to PostShiba. See return-path.

About

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