HAProxy SSL Problem

Hello,
we have the following problem and couldn’t find any solution.

First what we want to do: We have a network, where we have a Server for Nextcloud and another Server for collabora (we seperated these two because of storage issues). We use a OPNsense Firewall where we installed the haproxy. every request for the collabora server should be forwarded to the collabora server. we want to use ssl (https) all the way from the incoming request till the server.

the problem: the server can be reached directly with the port 443. but if we want to reach the server across the haproxy we get a ssl error und we cannot find a solution.

any ideas? or any forum topics or sites you can suggest?

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