For ASA failover you can do a LAN based failover in which one ethernet interface in both the devices will be used to share stateful failover information and one ethernet interface on both will be used as LAN failover interfaces. When you have configured failover properly and do a "write mem" on Active unit, the config will get replicated on the other unit as well so there will be no need to copy the config manually to the other unit. Following links may help you
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...