2851 router vpn to 851 router lan clients cannot ping

Question

Greets - I'm expanding my lab experience by adding a 2851 router to my mix of 18xx and 851/871 units. Some of this infrastructure is in production, some just lab work. I have established good connectivity between 18xx's and 851/871's with IPSEC VPNs (site-to-site static and dynamic), but my problem is with adding in a 2851.
Setup: 2851 with 12.4 ADVENTK9, WAN on GE0/0 as 216.189.223.bbb/26, LAN on GE0/1 as 172.20.0.1/20 (VPN module, but no additional HWIC modules)
851 with 12.4 ADVENTK9, WAN on FE4 as 216.53.254.aaa/24, LAN on FE0..3 via BVI1 as 172.21.1.1/24
The two router WAN ports are bridged via a 3rd router (a Zywall with 216.0.0.0/8 route, with the router at 216.1.1.1) affectionately called the "InterNOT", which provides a surrogate to the great web, minus actual other hosts and dns, but it doesn't matter. As both my WAN addresses are within 216.x.x.x, this works quite well. This surrogate has tested fine and is known to not be part of a problem.
The 851 has been tested against another 851 with complementary setup and a successful VPN can run between the two.
I have good LAN-WAN connections on each router. I do have a "Good" VPN connection between the two routers.
The problem: I cannot ping from a LAN host on 172.20.x.x on the 2851 to any 172.21.1.x (eg 172.21.1.1) host on the 851, and vice versa.
From a LAN host, I can ping to my InterNOT - for example a dhcp host 172.20.6.2 on the 2851 LAN can ping 216.1.1.1 fine. I can also ping the 851's WAN address at 216.53.254.aaa.
To complicate matters, if I connect to the routers via console, I CAN ping across the vpn to the destination LAN hosts, in both directions.
This seems to indicate that there is a bridging problem between the LAN interfaces to the VPN interfaces. I suspect this is a config problem on the 2851, as I have had a similar config working on my 851 to 851 site-to-site setups. I also suspect it is in the 2851's config as I'm still just starting out with this particular router.
So some stripped-down configs:
For the 2851:
no service config
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
hostname router2851
boot-start-marker
boot-end-marker
no logging buffered
no logging console
enable password mypassword2
no aaa new-model
dot11 syslog
no ip cef
no ip dhcp use vrf connected
ip dhcp excluded-address 172.20.0.1 172.20.6.1
ip dhcp excluded-address 172.20.6.254 172.20.15.254
ip dhcp pool Internal_2000
   import all
   network 172.20.0.0 255.255.240.0
   domain-name myseconddomain.int
   default-router 172.20.0.1
   lease 7
no ip domain lookup
multilink bundle-name authenticated
voice-card 0
 no dspfarm
crypto pki <<truncated>>
crypto pki certificate chain TP-self-signed-2995823027
 <<truncated>>
      quit
username myusername privilege 15 password 0 mypassword2
archive
 log config
  hidekeys
crypto isakmp policy 1
 encr 3des
 authentication pre-share
 group 2
crypto isakmp key mysharedkey address 216.53.254.aaa
crypto ipsec transform-set ESP-3DES-SHA esp-3des esp-sha-hmac
crypto map SDM_CMAP_1 1 ipsec-isakmp
 description Tunnel to216.53.254.aaa
 set peer 216.53.254.aaa
 set transform-set ESP-3DES-SHA
 match address 100
interface GigabitEthernet0/0
 description $ETH-WAN$
 ip address 216.189.223.bbb 255.255.255.192
 ip nat outside
 ip virtual-reassembly
 duplex auto
 speed auto
 crypto map SDM_CMAP_1
 no shut
interface GigabitEthernet0/1
 description $FW_INSIDE$$ETH-LAN$
 ip address 172.20.0.1 255.255.240.0
 ip nat inside
 ip virtual-reassembly
 no ip route-cache
 duplex auto
 speed auto
 no mop enabled
ip forward-protocol nd
ip route 0.0.0.0 0.0.0.0 GigabitEthernet0/0
ip http server
ip http authentication local
ip http secure-server
ip dns server
ip nat inside source route-map SDM_RMAP_1 interface GigabitEthernet0/0 overload
access-list 1 remark CCP_ACL Category=2
access-list 1 permit 172.20.0.0 0.0.15.255
access-list 100 remark CCP_ACL Category=4
access-list 100 remark IPSec Rule
access-list 100 permit ip 172.20.0.0 0.0.15.255 172.21.1.0 0.0.0.255
access-list 101 remark CCP_ACL Category=2
access-list 101 remark IPSec Rule
access-list 101 deny   ip 172.20.0.0 0.0.15.255 172.21.1.0 0.0.0.255
access-list 101 permit ip 172.20.0.0 0.0.15.255 any
route-map SDM_RMAP_1 permit 1
 match ip address 101
control-plane
banner motd ~This is a private computer system for authorized use only. And Stuff~
line con 0
line aux 0
line vty 0 4
 privilege level 15
 password mypassword
 login local
 transport input telnet ssh
scheduler allocate 20000 1000
end
And for the 851:
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
hostname router851
boot-start-marker
boot-end-marker
logging buffered 52000 debugging
no logging console
enable password mypassword
aaa new-model
aaa authentication login default local
aaa authorization exec default local
aaa session-id common
resource policy
clock timezone PCTime -5
clock summer-time PCTime date Apr 6 2003 2:00 Oct 26 2003 2:00
no ip dhcp use vrf connected
ip dhcp excluded-address 172.21.1.1 172.21.1.100
ip dhcp pool Internal_2101
   import all
   network 172.21.1.0 255.255.255.0
   default-router 172.21.1.1
   domain-name mydomain.int
   dns-server 172.21.1.10
   lease 4
ip cef
ip domain name mydomain.int
ip name-server 172.21.1.10
crypto pki <<truncated>>
crypto pki certificate chain TP-self-signed-3077836316
 <<truncated>>
  quit
username myusername privilege 15 password 0 mypassword2
crypto isakmp policy 1
 encr 3des
 authentication pre-share
 group 2
crypto isakmp key mysharedkey address 216.189.223.aaa
crypto ipsec transform-set ESP-3DES-SHA esp-3des esp-sha-hmac
crypto ipsec transform-set ESP-3DES-SHA1 esp-3des esp-sha-hmac
crypto ipsec transform-set ESP-3DES-SHA2 esp-3des esp-sha-hmac
crypto map SDM_CMAP_1 1 ipsec-isakmp
 description Tunnel to216.189.223.bbb
 set peer 216.189.223.bbb
 set transform-set ESP-3DES-SHA2
 match address 100
bridge irb
interface FastEthernet0
 spanning-tree portfast
interface FastEthernet1
 spanning-tree portfast
interface FastEthernet2
 spanning-tree portfast
interface FastEthernet3
 spanning-tree portfast
interface FastEthernet4
 description $ETH-WAN$
 ip address 216.53.254.aaa 255.255.254.0
 ip nat outside
 ip virtual-reassembly
 ip tcp adjust-mss 1460
 duplex auto
 speed auto
 no cdp enable
 crypto map SDM_CMAP_1
 no shut
interface Vlan1
 description Internal Network
 no ip address
 ip nat inside
 ip virtual-reassembly
 bridge-group 1
 bridge-group 1 spanning-disabled
interface BVI1
 description Bridge to Internal Network
 ip address 172.21.1.1 255.255.255.0
 ip nat inside
 ip virtual-reassembly
ip route 0.0.0.0 0.0.0.0 FastEthernet4
ip route 172.21.1.0 255.255.255.0 BVI1
ip http server
ip http secure-server
ip nat inside source route-map SDM_RMAP_1 interface FastEthernet4 overload
access-list 1 remark CCP_ACL Category=2
access-list 1 permit 172.21.1.0 0.0.0.255
access-list 100 remark CCP_ACL Category=4
access-list 100 remark IPSec Rule
access-list 100 permit ip 172.21.1.0 0.0.0.255 172.20.0.0 0.0.15.255
access-list 101 remark CCP_ACL Category=2
access-list 101 remark IPSec Rule
access-list 101 deny   ip 172.21.1.0 0.0.0.255 172.20.0.0 0.0.15.255
access-list 101 remark IPSec Rule
access-list 101 deny   ip 172.21.1.0 0.0.0.255 172.21.101.0 0.0.0.31
access-list 101 permit ip 172.21.1.0 0.0.0.255 any
route-map SDM_RMAP_1 permit 1
 match ip address 101
control-plane
bridge 1 route ip
banner motd ~This is a private computer system for authorized use only. And Stuff.~
line con 0
 password mypassword
 no modem enable
line aux 0
line vty 0 4
 password mypassword
scheduler max-task-time 5000
end
Note that the above are somewhat stripped-down configs, without firewall or WAN ACL's - interestingly my default WAN-Inbound ACLs seem to break connectivity when included, so I realize I have some more cleanup to do there, but the 2851 LAN bridging seems to be what I should concentrate on first.
I'm still googling some of the particulars with the 2851, but any assistance is appreciated.
Regards,
Ted.

Answer 1

Hi,
First,please delete NAT.If we configured the NAT in the RRAS,the source IP address in all packets sent to 192.168.1.0/24 would be translated to 192.168.1.224.
Second,please enable the LAN routing in RRAS server.To enable LAN routing,please follow the steps below,
1.In the RRAS server,Open Routing and Remote Access.
2.Right-click the server name,then click
properties.
3.On the General tab,select
IPv4 Router check box,and then click Local area network(LAN) routing only.
Then,announce the 172.16.0.0 network to the router.
To learn more details about enabling LAN routing, please refer to the link below,
http://technet.microsoft.com/en-us/library/dd458974.aspx
Best Regards,
Tina