# Partial reverse-proxy coverage - Docs

The partial reverse-proxy coverage check fires when some of your hostnames send events through a [reverse proxy](/docs/advanced/proxy.md) but others don't. It's a more subtle cousin of the [no reverse proxy](/docs/health-checks/no-reverse-proxy.md) check.

![Partial reverse-proxy coverage check in the Health checks section in the PostHog app](https://res.cloudinary.com/dmukukwp6/image/upload/w_1000,c_limit,q_auto,f_auto/pasted_image_2026_06_24_T19_51_47_886_Z_8eef00f253.png)![Partial reverse-proxy coverage check in the Health checks section in the PostHog app](https://res.cloudinary.com/dmukukwp6/image/upload/w_1000,c_limit,q_auto,f_auto/pasted_image_2026_06_24_T19_51_41_323_Z_f33ec8ce4e.png)

## What this check looks for

Once a day, the check groups your recent `$pageview` / `$screen` events by hostname (looking only at hosts with at least 50 events over the last week) and checks, per host, whether traffic goes through a custom API host. If at least one host is proxied and at least one isn't, it raises a **warning** and lists the unproxied hosts in the issue.

## Why it matters

Traffic from the unproxied hosts is more likely to be blocked by ad blockers and to have inaccurate geolocation. That makes your analytics inconsistent across domains – one site looks healthy while another silently undercounts – which is hard to spot without this check.

## Fix it manually

1.  Open the **Web analytics health** page. It lists the hostnames that aren't going through a proxy.
2.  For each of those, point the SDK's `api_host` at your reverse proxy – the same proxy your other domains already use – and redeploy.

## Fix it automatically with the Inbox and PostHog Code

With the [Inbox](/docs/self-driving.md) and health checks enabled as a [signal source](/docs/self-driving/inbox/sources.md), the agent will:

-   Read the unproxied hosts from the issue and verify coverage per host in your data.
-   Check your existing proxies and, for the deployments serving those hosts, set `api_host` to the existing reverse proxy URL (adding a route, or a new managed proxy, for any host that doesn't have one yet).
-   Open a PR.

The issue clears on the next run once every host is proxied.

## Related

-   [Health checks overview](/docs/health-checks.md)
-   [No reverse proxy](/docs/health-checks/no-reverse-proxy.md)
-   [Reverse proxy](/docs/advanced/proxy.md)

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