Assistance in Irule

Try a minor modification:

when HTTP_REQUEST { 
    if { [string tolower [HTTP::host]] equals "learning.abc.com" } { 
        HTTP::redirect "http://inside.abc.com/learn[HTTP::uri]" 
    } 
}

This will add the requested URI to the end of the redirect URI. If nothing is requested (no URI), then the minimum will be "/", as in

http://inside.abc.com/learn/