I have 1800 series NAT enable router. F0/0 have primary (local lan ip) and seconady ip (valid pool ip).My nw is working smoothely but sueddenly in each 4-5 days some users unable to access the internet. As i remove the statis nat cmd from router and paste it back, users able to access the internet. Even after clearing the translations table problem presist same. The only soution is to remove nat cmd once and past it back. This proble occure randomely. Why it is so. Pls help me out.