Keeping your redirects working is very important. But even if your redirect is working, and the destination isn't reachable, the user still get an error.
Broken destination monitoring helps by checking the destination to ensure it's reachable.
Destination monitoring can be enabled in your Team settings: (Pro plan and up)

You can also overrule the general Team setting for a specific destination:

If monitoring is enabled, we automatically check the destinations every hour. If a destination is broken you will see it on your redirects overview and we will notify you in the Summary email.
When you click on the specific redirect that has a broken destination, you can see more details about this. You can also trigger a 'Recheck' by clicking on the icon below 'Last checked at'.

Probes locations
We monitor destinations using multiple uptime probes from different locations. Each probe checks the destination URL, and if any probe returns a successful response, we mark the destination as up.
This helps prevent false downtime reports for destinations that may block traffic based on geolocation. For example, a destination might be reachable from the US but blocked from the EU.
User agent allowlist
We'll send requests to your destination with the User Agent set to:
Mozilla/5.0 (compatible; redirect.pizza/1.0; +https://redirect.pizza/destination-monitor)
IP allowlist
To create an allowlist based on IP addresses, our outbound IPs may be found via the following link:
JSON format: https://redirect.pizza/.well-known/ips.json
.txt format: https://redirect.pizza/.well-known/ips.txt
To only include IPv4 or IPv6 addreses, you may specify the format:
https://redirect.pizza/.well-known/ips-v4.json
https://redirect.pizza/.well-known/ips-v6.json
Important note: these IP addresses are subject to change in the future!
Request signing
We sign every outgoing broken destination monitor request with the HTTP Message Signatures standard (RFC 9421). Each request includes a `Signature` & `Signature-Input` header. You can validate based on our public key below, that we're the originators of the request.
Our public key can be found at: https://redirect.pizza/.well-known/http-message-signatures-directory
