Добрый вечер, столкнулся с проблемой :)
был поднят gre+ipsec туннель между роутерами циско 850, сменился провайдер, и я просто поменял ip адреса,но туннель перестал подниматься. Внешние интерфейсы пингуются на цисках.
как понять в чем проблема?
офис1

router1#sh run
Building configuration...
Current configuration : 2436 bytes
!
version 12.4
no service pad
service tcp-keepalives-in
service tcp-keepalives-out
service timestamps debug datetime msec localtime show-timezone
service timestamps log datetime msec localtime show-timezone
service password-encryption
service sequence-numbers
no service dhcp
!
hostname router1
!
boot-start-marker
boot-end-marker
!
logging buffered 51200 debugging
logging console critical
enable secret 5 хххххххххххххххххххххххххххх
!
no aaa new-model
!
resource policy
!
clock timezone PCTime 3
no ip subnet-zero
no ip source-route
!
!
ip cef
ip tcp synwait-time 10
no ip bootp server
no ip domain lookup
ip ssh time-out 60
ip ssh authentication-retries 2
!
!
!
username admin privilege 15 secret 5 ххххххххххххххххххххххх
!
!
!
crypto isakmp policy 30
 hash md5
 authentication pre-share
crypto isakmp key superpassword address 81.94.153.хх no-xauth
!
!
crypto ipsec transform-set TSZT esp-des esp-md5-hmac
 mode transport
!
crypto map CM 10 ipsec-isakmp
 set peer 81.94.153.хх
 set transform-set TSZT
 match address 101
!
!
!
interface Tunnel0
 ip address 192.168.100.1 255.255.255.252
 ip mtu 1400
 ip virtual-reassembly
 tunnel source FastEthernet4
 tunnel destination 81.94.152.хх
 tunnel path-mtu-discovery
!
interface FastEthernet0
!
interface FastEthernet1
!
interface FastEthernet2
!
interface FastEthernet3
!
interface FastEthernet4
 description Link 
 ip address 81.94.143.хх 255.255.255.248
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ip virtual-reassembly
 ip route-cache flow
 duplex auto
 speed auto
 crypto map CM
!
interface Vlan1
 description Link LAN
 ip address 192.168.0.230 255.255.255.0
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ip route-cache flow
 ip tcp adjust-mss 1352
!
no ip classless
ip route 0.0.0.0 0.0.0.0 81.94.143.хх
ip route 192.168.1.0 255.255.255.0 Tunnel0
!
no ip http server
ip http authentication local
no ip http secure-server
ip http timeout-policy idle 60 life 86400 requests 10000
!
logging trap debugging
access-list 101 permit gre host 81.94.143.хх host 81.94.153.хх
no cdp run
!
control-plane
!
banner login ^CAuthorized access only!
 Disconnect IMMEDIATELY if you are not an authorized user!^C
!
line con 0
 login local
 no modem enable
 transport output telnet
line aux 0
 login local
 transport output telnet
line vty 0 4
 privilege level 15
 login local
 transport input telnet ssh
!
scheduler max-task-time 5000
no scheduler allocate
end

офис2

router2#sh run
Building configuration...
Current configuration : 1984 bytes
!
version 12.4
no service pad
service tcp-keepalives-in
service tcp-keepalives-out
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
service sequence-numbers
no service dhcp
!
hostname router2
!
boot-start-marker
boot-end-marker
!
enable secret 5 хххххххххххххххххххххххххххх
!
no aaa new-model
!
resource policy
!
clock timezone PCTime 3
ip subnet-zero
!
!
ip cef
no ip domain lookup
!
!
!
username admin privilege 15 password 7 ххххххххххххххххххххххх
!
!
!
crypto isakmp policy 30
 hash md5
 authentication pre-share
crypto isakmp key superpassword address 81.94.143.хх no-xauth
!
!
crypto ipsec transform-set TSZT esp-des esp-md5-hmac
 mode transport
!
crypto map CM 10 ipsec-isakmp
 set peer 81.94.143.хх
 set transform-set TSZT
 match address 101
!
!
!
interface Tunnel0
 ip address 192.168.100.2 255.255.255.252
 ip mtu 1400
 ip virtual-reassembly
 tunnel source FastEthernet4
 tunnel destination 81.94.143.хх
 tunnel path-mtu-discovery
!
interface FastEthernet0
!
interface FastEthernet1
!
interface FastEthernet2
!
interface FastEthernet3
!
interface FastEthernet4
 description Link Astel telecom
 ip address 81.94.153.хх 255.255.255.248
 ip virtual-reassembly
 duplex auto
 speed auto
 crypto map CM
!
interface Vlan1
 description Link LAN
 ip address 192.168.1.231 255.255.255.0
 no ip redirects
 no ip unreachables
 no ip proxy-arp
 ip virtual-reassembly
 ip route-cache flow
 ip tcp adjust-mss 1352
!
no ip classless
ip route 0.0.0.0 0.0.0.0 81.94.153.хх
ip route 192.168.0.0 255.255.255.0 Tunnel0
!
no ip http server
no ip http secure-server
!
access-list 101 permit gre host 81.94.153.хх host 81.94.143.хх
!
control-plane
!
!
line con 0
 login local
 no modem enable
 transport output telnet
line aux 0
 login local
 transport output telnet
line vty 0 4
 privilege level 15
 login local
 transport input telnet ssh
!
scheduler max-task-time 5000
end

заранее спасибо за любой ответ

пс раньше провайдер  был через выделеную линию а теперь черз адсл модем.