Hello,
Using a 2951 router, i need to translate addresses. This seems to work "sometimes". I cannot find the reason, why it does not work in all cases.
IOS-Version: c2951-universalk9_npe-mz.SPA.151-4.M6.bin
The interfaces are defined as follows:
interface GigabitEthernet0/1
ip address 193.83.51.13 255.255.255.248
ip nat inside
ip virtual-reassembly in
!
interface GigabitEthernet0/2
ip address 10.255.82.26 255.255.255.248
ip nat outside
ip virtual-reassembly in
!
Together with the static route-definitions
ip route 172.16.0.0 255.240.0.0 193.83.51.9 via g0/1
ip route 10.82.192.0 255.255.192.0 193.83.51.9
the "show ip route" identify the following routes (other routes are provided by OSPF and BGP which is not shown here):
S 172.16.0.0/12 [10/0] via 193.83.51.9
O 10.82.0.0/16 is a summary, 7w0d, Null0
S 10.82.192.0/18 [10/0] via 193.83.51.9
S 10.202.0.0/16 [10/0] via 193.83.51.9
B 10.202.132.37/32 [20/0] via 10.255.82.25, 3d00h via g0/2
B 10.111.40.0/25 [20/0] via 10.255.82.25, 01:18:44
When i use the following NAT-Definitions
ip nat pool p220 10.82.220.1 10.82.223.254 netmask 255.255.252.0
ip nat inside source list al220 pool p220
ip access-list standard al220
permit 172.28.0.0 0.3.255.255
ip nat pool p237 10.82.237.65 10.82.237.254 netmask 255.255.255.0
ip nat inside source list al237 pool p237
ip access-list standard al237
permit 193.83.48.0 0.0.3.255
ip nat outside source static 10.202.132.37 10.111.40.37
The connection seems to work. It shows:
trace 10.111.40.37 source 193.83.51.13
<suppressed>
show ip nat trans | inc 10.111.40.37
--- --- --- 10.111.40.37 10.202.132.37
udp 10.82.237.65:49226 193.83.51.13:49226 10.111.40.37:33434 10.202.132.37:33434
udp 10.82.237.65:49227 193.83.51.13:49227 10.111.40.37:33435 10.202.132.37:33435
udp 10.82.237.65:49228 193.83.51.13:49228 10.111.40.37:33436 10.202.132.37:33436
However, if i change 'trace' to 'ping' it will no longer work:
ping 10.111.40.37 source 193.83.51.13
show ip nat trans | inc 10.111.40.37
--- --- --- 10.111.40.37 10.202.132.37
icmp 10.82.237.65:5 193.83.51.13:5 10.111.40.37:5 10.111.40.37:5
It will also fail if a source-interface beyond the 'inside-connection' is used.:
show ip nat trans | inc 10.111.40.37
--- --- --- 10.111.40.37 10.202.132.37
tcp 10.82.220.162:49639 172.30.37.100:49639 10.111.40.37:80 10.111.40.37:80
tcp 10.82.220.162:49640 172.30.37.100:49640 10.111.40.37:80 10.111.40.37:80
tcp 10.82.220.162:49641 172.30.37.100:49641 10.111.40.37:80 10.111.40.37:80
Inside-translation is correct in any case but outside-translation fails somtimes.
Can someone tell me, where the problem is?
Regards
