Site-to-site VPN not working tunnel is up but no decaps
From the fact that there are IPSec SAs it would indicate that the crypto negotiation was successful. It shows that you are sending traffic over the tunnel but not receiving traffic. I would suggest checking on the Juniper for possible mismatches. I would check in particular that their traffic selector matches your crypto access list and check that they are not translating the traffic that will come over the VPN tunnel.
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...