It sounds like a shared secret mismatch between your server and the device. Since TACACS+ encrypts the entire packet, if the shared secret is off then each device recieves garble for their "communication"
I would check to make sure the shared secrets match. What could be the issue is the command
tacacs-server host x.x.x.x key 7 "clave"
the 'key 7' bit indicates that a previously hashed password will be put here. I would use the
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...