What is the service for checking the integrity of the download site?

Question

Computer networks

Good afternoon.
Tell me a service to check the integrity of the site loading (i.e. so that all data is loaded: pictures, banners, etc.), and in case of an error (404, 503, etc. on one of the links), an alert was sent to the mail .
Or maybe you can do it on your own?
In fact, you need software that is similar to the Xenu program, but works offline.
Thank you.

Answer 1

just look at the logs for 404 and 503