Cisco →  Доступ между интерфейсами на Cisco ASA

Если Вы хотите разрешить хождение пакетов между двух подсетей, которые находятся на разных портах, Вам необходимо включить 2 опции. По стандарту хождение между интерфейсами запрещено.

Конфигурация:

interface GigabitEthernet0/1
 description Local network
 nameif inside
 security-level 100
 ip address 192.168.37.254 255.255.255.0
 ospf cost 10
!
interface GigabitEthernet0/2
 description Local2 network
 nameif inside2
 security-level 100
 ip address 192.168.38.254 255.255.255.0
 ospf cost 10
!

same-security-traffic permit inter-interface
same-security-traffic permit intra-interface

Жирным выделены необходимые опции.

Если же нужны ограничения, то их можно создать с помощью access-list.

Cisco →  Cisco ASA L2L VPN

!
access-list inside_nat0_outbound extended permit ip 192.168.37.0 255.255.255.0 172.21.0.0 255.255.255.0
access-list outside_1_cryptomap extended permit ip 192.168.37.0 255.255.255.0 172.21.0.0 255.255.255.0
!
nat (inside) 0 access-list inside_nat0_outbound
!
crypto ipsec transform-set ESP-3DES-SHA esp-3des esp-sha-hmac
crypto ipsec security-association lifetime seconds 28800
crypto ipsec security-association lifetime kilobytes 4608000
!
crypto map outside_map 1 match address outside_2_cryptomap
crypto map outside_map 1 set pfs
crypto map outside_map 1 set peer 200.1.2.3
crypto map outside_map 1 set transform-set ESP-3DES-SHA
crypto map outside_map 1 set ...

Cisco →  Cisco Easy VPN Server

aaa new-model
!
!
aaa authentication login default local
aaa authentication login userauthen local
aaa authorization network vpn-group local 
!
username #user# password 7 #pass#
!
crypto isakmp client configuration group cvpn
 key #KEYS#
 dns 10.0.0.1
 domain local
 pool RVPN
!
crypto ipsec transform-set VPNTRANS esp-3des esp-sha-hmac
!
crypto map VPN client authentication list userauthen
crypto map VPN isakmp authorization list vpn-group
crypto map VPN client configuration address respond
!
crypto map VPN 65535 ipsec-isakmp dynamic VPN
!
interface FastEthernet0/1
 description $ETH-WAN$
 ip address 100.100.100.1 255.255.255.248
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ip nat outside ...

Cisco →  Конфиг Cisco lan to lan VPN

!
crypto isakmp policy 1
 encr 3des
 hash md5
 authentication pre-share
 group 2
!
crypto isakmp key 123456 address 100.100.100.100 no-xauth
!
crypto ipsec security-association lifetime seconds 28800
crypto ipsec security-association idle-time 600
!
crypto ipsec transform-set vpnTRANS esp-3des esp-md5-hmac 
!
crypto map VPN 10 ipsec-isakmp 
 set peer 100.100.100.100
 set transform-set vpnTRANS 
 match address 101
!

interface FastEthernet0/0
 description $ETH-LAN$
 ip address 172.21.0.2 255.255.255.0
 ip access-group 1 in
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ip nat inside
 ip virtual-reassembly
 duplex auto
 speed auto
 no snmp trap link-status
 no mop enabled ...