I have a asa5520-k8 with 7.2(4) that I found an NAT that was missing but before I can enter it I had run two commands below in order to enter it and I need to understand why if the xlate entry did not exist..
no alias (inside) 10.120.208.26 172.27.208.26 255.255.255.255
alias (inside) 10.120.208.26 172.27.208.26 255.255.255.255