# Sentry: events go nowhere, DSN host does not match the org

## The symptom

DSN looks right, project slug matches, but events never arrive and debug output shows connection failures or 403s.

## The cause

The DSN embeds the ingest host, and it must match where the organization actually lives:

- SaaS orgs get an org-specific ingest host, shown on the project's Client Keys page. Copy it from there; do not construct it by hand.
- EU-region orgs use a different ingest host than US orgs. A US DSN pasted into an EU org's config (or the reverse) fails.
- Self-hosted: the DSN host must be your instance URL. A sentry.io DSN in a self-hosted deploy (or vice versa) posts events to a stranger.

Hand-typed DSNs are the root cause almost every time. The project ID, the key, and the host all have to come from the same Client Keys page.

## Confirmation

Read the exact DSN the process uses (print it at startup in debug, or echo the env var in CI) and compare host, key, and project ID against Settings > Projects > [project] > Client Keys (DSN). All three segments must match.

## Fix and verify

Paste the canonical DSN, redeploy, and send one test error. For self-hosted, also align `SENTRY_URL` for the CLI, since SDK and CLI are configured independently and can disagree about which Sentry they talk to.