This is possibly/probably due to my weird setup, which is that I have apache behind nginx, with the result that apache sees the client's IPv4 address as having been mapped to IPv6. i.e. <tt>::ffff:10.11.12.13</tt>. That being the case, I currently need to specify that (with the <tt>::ffff:</tt> prepended) if I want to whitelist (or more importantly blacklist) and IPv4 address.
This is possibly/probably due to my weird setup, which is that I have apache behind nginx, with the result that apache sees the client's IPv4 address as having been mapped to IPv6. i.e. <tt>::ffff:10.11.12.13</tt>. That being the case, I currently need to specify that (with the <tt>::ffff:</tt> prepended) if I want to whitelist (or more importantly blacklist) and IPv4 address.