Hi, Im trying to dicypher your ip scheme and Im seeing something odd,
"ONly remote access client 172.28.31.128/248 is not able to reach anywhere."
you are using 172.28.31.128 for your vpn pool network with a 29bit mask, at least this is what your description entails , this network allows for a range of 8 addresses from 128 to 135, the 172.28.31.128 is the network addresss therefore it cannot be used for assigning it to any host, and 135 is broadcast address.
On the concentrator in your vpn tunnel group for RA clients , under Client config tab do you have IPsec over UDP checked on, as well as IPec over udp port 1000, this is asuming clients are using default Ipsec over UDP port 1000 in their client settings.
You may also need to enable NAT-transparency under Tunneling Protocol\IPsec\NAT Transparency (Ipsec over NAT-T).
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...