Forum Moderators: phranque
As noted in the documentation, do not enable forward proxying, as this presents a security risk and is not needed in the present case.
Note that all requests proxied through abc.org will appear to originate from the abc.org server; If you want to log the actual client IP addresses on abc.net, you will have to configure abc.org to forward those client IP addresses in the HTTP X-Forwarded-For header, and configure the abc.net server to log X_Forwarded_For instead of REMOTE_ADDR if the X-Forwarded-For header is not blank.
This is an advanced hosting setup; If you are not fully-versed in configuring proxy servers, there is the possibility of potentially-serious problems. If abc.net is an IIS server, you will need both Apache and IIS expertise, and this will make it even more difficult. Therefore, you should consider paying your host or a consultant to do this configuration for you unless you're comfortable with doing it yourself.
Jim