I thought I'd forwarded the router's (DSR-250 rev. A2 fw. 2.11) TCP/22 to a machine on LAN using the router's preconfigured "SSH:TCP" service.
Does the following look right to you?
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When trying to login from a remote client using the right username/password I am getting the
Permission denied, please try again error every time.
Could it be that the SSH request is actually being processed by the router and not forwarded to the destination?