Hello Network Admins,
I need your help here configuring additional Site to Site VPN on Cisco router.
Note: Site-A = Head office
Site-B= Branch office -----------> Public IP : 87.101.54.74
Site-C= Branch office -----------> Public IP : 87.101.80.94
Site to Site VPN is configured between Site A to B and Site A to C. However, I am trying to configure Site to Site VPN from Branch office to Branch office Site-B to Site-C. Here is my existing Site to Site VPN running configuration which is connected to head office. Please let me know what can be done to configure branch office to Branch office? Thank you.
Site B#show run
Building configuration...
Current configuration : 2672 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname SIT
!
boot-start-marker
boot system flash flash:c2800nm-advsecurityk9-mz.124-15.T9.bin
boot system flash flash:c2800nm-ipbase-mz.124-15.T10.bin
boot-end-marker
!
logging buffered 51200 warnings
enable secret 5 $1$UC784zH75YQO..fhY6S.ar0
enable password asdf
!
no aaa new-model
dot11 syslog
!
!
ip cef
no ip dhcp use vrf connected
!
ip dhcp pool DSL
network 10.11.4.0 255.255.255.0
default-router 10.11.4.1
dns-server 208.67.222.222
!
!
ip domain name yourdomain.com
!
multilink bundle-name authenticated
!
!
!
!
!
username admin privilege 15 secret 5 $ghjikhggfffd
archive
log config
hidekeys
!
!
crypto isakmp policy 1
encr 3des
authentication pre-share
group 2
crypto isakmp key ijklmnopq address 87.101.158.218 no-xauth
!
!
crypto ipsec transform-set VPN_ITC_TS esp-aes esp-sha-hmac
!
crypto map VPN_ITC 10 ipsec-isakmp
set peer 87.101.158.218
set transform-set VPN_ITC_TS
match address 135
!
!
!
!
class-map match-any Servers-List
match access-group 190
!
!
policy-map Servers
class Servers-List
bandwidth percent 50
!
!
!
!
interface FastEthernet0/0
description WAN ITC
bandwidth 2048
ip address 87.101.54.74 255.255.255.252
ip nat outside
ip virtual-reassembly
duplex auto
speed auto
crypto map VPN_ITC
service-policy output Servers
!
interface FastEthernet0/1
description LAN ITC
ip address 10.11.4.1 255.255.255.0
ip nat inside
ip virtual-reassembly
duplex auto
speed auto
!
ip forward-protocol nd
ip route 0.0.0.0 0.0.0.0 87.101.54.73
ip route 87.101.158.216 255.255.255.252 87.101.54.73
ip route 192.168.0.0 255.255.0.0 87.101.54.73
!
!
ip http server
ip http access-class 23
ip http authentication local
no ip http secure-server
ip http timeout-policy idle 60 life 86400 requests 10000
ip nat inside source list 138 interface FastEthernet0/0 overload
!
access-list 135 permit ip 10.11.4.0 0.0.0.255 192.168.0.0 0.0.255.255
access-list 138 deny ip 10.11.4.0 0.0.0.255 192.168.0.0 0.0.255.255
access-list 138 permit ip 10.11.4.0 0.0.0.255 any
access-list 190 remark List of Servers to be assigned QOS
access-list 190 permit ip any host 192.168.50.1
access-list 190 permit ip any host 192.168.50.13
access-list 190 permit ip any host 192.168.50.15
access-list 190 permit ip any host 192.168.50.21
access-list 190 permit ip any host 192.168.50.22
access-list 190 permit ip any host 192.168.50.24
!
!
!
!
control-plane
!
!
line con 0
login local
line aux 0
line vty 0 4
login local
transport input telnet
!
scheduler allocate 20000 1000
!
end
Site-C configuration: -
Current configuration : 2859 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname SIT
!
boot-start-marker
boot system flash flash:c2800nm-advsecurityk9-mz.124-15.T9.bin
boot system flash flash:c2800nm-ipbase-mz.124-15.T10.bin
boot-end-marker
!
logging buffered 51200 warnings
enable password 7 0101565446764F1E2837253221
!
no aaa new-model
dot11 syslog
!
!
ip cef
no ip dhcp use vrf connected
!
ip dhcp pool DSL
network 10.11.10.0 255.255.255.0
default-router 10.11.10.1
dns-server 208.67.222.222
!
!
ip domain name yourdomain.com
!
multilink bundle-name authenticated
!
!
!
!
!
username awalnet privilege 15 secret 5 $1$O9C6$hGhgghd4.L7ULalS7Wt/
archive
log config
hidekeys
!
!
crypto isakmp policy 1
encr 3des
authentication pre-share
group 2
crypto isakmp key 5O15B67n address 87.101.158.218 no-xauth
!
!
crypto ipsec transform-set VPN_ITC_TS esp-aes esp-sha-hmac
!
crypto map VPN_ITC 10 ipsec-isakmp
set peer 87.101.158.218
set transform-set VPN_ITC_TS
match address 135
!
!
!
!
class-map match-any Servers-List
match access-group 190
!
!
policy-map Servers
class Servers-List
bandwidth percent 50
!
!
!
!
interface FastEthernet0/0
description WAN Link to ITC
bandwidth 2048
ip address 87.101.80.94 255.255.255.252
ip nat outside
ip virtual-reassembly
duplex auto
speed auto
crypto map VPN_ITC
service-policy output Servers
!
interface FastEthernet0/1
description LAN
ip address 10.11.10.1 255.255.255.0
ip nat inside
ip virtual-reassembly
duplex full
speed 100
!
ip forward-protocol nd
ip route 0.0.0.0 0.0.0.0 87.101.80.93
ip route 87.101.158.216 255.255.255.252 87.101.80.93
ip route 192.168.0.0 255.255.0.0 87.101.80.93
!
!
ip http server
ip http access-class 23
ip http authentication local
no ip http secure-server
ip http timeout-policy idle 60 life 86400 requests 10000
ip nat inside source list 138 interface FastEthernet0/0 overload
!
access-list 135 permit ip 10.11.10.0 0.0.0.255 192.168.0.0 0.0.255.255
access-list 138 deny ip 10.11.10.0 0.0.0.255 192.168.0.0 0.0.255.255
access-list 138 permit ip 10.11.10.0 0.0.0.255 any
access-list 190 remark List of Servers to be assigned QOS
access-list 190 permit ip any host 192.168.50.1
access-list 190 permit ip any host 192.168.50.13
access-list 190 permit ip any host 192.168.50.15
access-list 190 permit ip any host 192.168.50.21
access-list 190 permit ip any host 192.168.50.22
access-list 190 permit ip any host 192.168.50.24
!
!
!
!
control-plane
!
!
line con 0
login local
line aux 0
line vty 0 4
privilege level 15
login local
transport input telnet
line vty 5 15
access-class 23 in
privilege level 15
login local
transport input telnet
!
scheduler allocate 20000 1000
!
end
Note: IPs and passwords are edited just for understanding. Thank you.
chments. 
