1
00:00:08,120 --> 00:00:13,520
This is one of multiple videos discussing network translation on the net.

2
00:00:13,910 --> 00:00:20,810
In this scenario we've been told that devices on the inside of our network such as Rotto one acting

3
00:00:20,810 --> 00:00:29,500
as PC one Rotto for acting as PC two and five acting as PC three are not able to ping Google.

4
00:00:29,600 --> 00:00:35,990
In other words 8 8 8 8 in this typology Rodda 3 is configured as Google.

5
00:00:36,200 --> 00:00:37,980
So let's do some verification.

6
00:00:38,110 --> 00:00:48,840
Here's wrote of one acting as PC one at the top can ping 8 8 8 8 as we can see in the output it's not

7
00:00:48,840 --> 00:00:53,920
able to ping the google address show IP run.

8
00:00:54,160 --> 00:01:04,770
We do have a static default dropped to 10 1 1 2 5 4 which is the IP address of router to acting as on

9
00:01:04,770 --> 00:01:06,680
NAT router.

10
00:01:06,710 --> 00:01:12,740
So let's do a trace 2 8 8 8 8 to speed things up.

11
00:01:12,800 --> 00:01:18,560
Type No IP domain lookup do that again.

12
00:01:18,610 --> 00:01:23,320
So we hit the default gateway but we don't go any further just to that again.

13
00:01:23,320 --> 00:01:32,250
So Trace 2 8 8 8 8 it gets to the default gateway which is routed to but doesn't get any further.

14
00:01:32,310 --> 00:01:37,770
So you can write it to ping Google ping 8 8 8 8.

15
00:01:37,840 --> 00:01:38,590
Yes it can.

16
00:01:38,650 --> 00:01:42,680
It can ping the Google IP address of quadripolar 8.

17
00:01:42,790 --> 00:01:43,830
This is on Natrajan.

18
00:01:43,840 --> 00:01:54,850
So let's do some not debugs de-bug IP Knecht Precentor that debugging has now enabled ping from radio

19
00:01:54,850 --> 00:02:03,580
one to Google we not getting any output in the next debug show IP not translations.

20
00:02:04,030 --> 00:02:08,900
They know not to translations show IP not statistics.

21
00:02:09,280 --> 00:02:12,350
OK so can you find the problem.

22
00:02:12,370 --> 00:02:18,410
Can you see where the issue is in this output notice here.

23
00:02:18,470 --> 00:02:21,080
Total active translations is zero.

24
00:02:21,500 --> 00:02:24,790
We had Peke translations previously of two.

25
00:02:25,050 --> 00:02:29,060
And here's the problem there are no outside interfaces.

26
00:02:29,090 --> 00:02:32,510
They are only inside interfaces.

27
00:02:32,660 --> 00:02:38,200
Gigabit 0 0 0 1 0 2 0 3 are configured as inside interfaces.

28
00:02:38,450 --> 00:02:41,560
Looking at rodded to use interfaces that's incorrect.

29
00:02:41,900 --> 00:02:42,590
This interface.

30
00:02:42,590 --> 00:02:43,120
Gigabit.

31
00:02:43,120 --> 00:02:45,560
0 1 is on the outside.

32
00:02:45,560 --> 00:02:48,060
In other words it's connected to the Internet.

33
00:02:48,200 --> 00:02:51,200
These three interfaces are on the inside.

34
00:02:51,200 --> 00:02:55,610
In other words they are on the local LAN and they should be nutted.

35
00:02:55,630 --> 00:02:59,170
So before I do a change let's look at the config.

36
00:02:59,530 --> 00:03:02,630
This interface is inside.

37
00:03:02,740 --> 00:03:06,650
According to the configuration this interface is the inside.

38
00:03:06,850 --> 00:03:08,050
According to the config.

39
00:03:08,080 --> 00:03:12,390
But according to the topology that should be the outside.

40
00:03:12,760 --> 00:03:19,890
So that's wrong of interfaces or configured correctly as the inside interface.

41
00:03:19,930 --> 00:03:21,950
But we need to change gigabit.

42
00:03:21,970 --> 00:03:26,200
0 1 and make that the outside interface.

43
00:03:26,230 --> 00:03:28,600
Notice the problem when I hit enter.

44
00:03:28,650 --> 00:03:35,800
We are told that it's inside so no IP net inside IP Nat outside.

45
00:03:36,200 --> 00:03:37,700
So we've made it the outside interface.

46
00:03:37,700 --> 00:03:48,410
Now show IP Nat statistics shows us that gigabit is 0 or 1 is the outside these three interfaces are

47
00:03:48,620 --> 00:03:50,750
inside interfaces.

48
00:03:50,750 --> 00:03:52,630
So in router one can we ping Google.

49
00:03:52,670 --> 00:03:54,090
Yes we can.

50
00:03:54,470 --> 00:03:56,950
We can see the translations on re-added too.

51
00:03:56,960 --> 00:04:05,860
So Source IP address of 10 1 1 1 was translated to 8 8 8 to 5 for destination being Google.

52
00:04:05,930 --> 00:04:10,970
We got the reply back and the reply was translated.

53
00:04:11,150 --> 00:04:12,510
So that looks good.

54
00:04:12,860 --> 00:04:25,670
What about Rotto 4 and 5 acting as internal hosts being 8 8 8 8 Ping's succeeds wrote a 5 ping 8 8 8

55
00:04:25,820 --> 00:04:27,810
8 Ping's succeeds.

56
00:04:28,280 --> 00:04:33,930
So we've resolved the network address translation issue in the apology.

57
00:04:33,980 --> 00:04:40,820
Don't forget you need to configure inside and outside interfaces correctly when configuring network

58
00:04:40,820 --> 00:04:43,020
address translation.

59
00:04:43,030 --> 00:04:46,980
I hope you found this video useful if it's been of benefit to you.

60
00:04:46,980 --> 00:04:50,990
Please like it and please subscribe to my YouTube channel.

61
00:04:51,040 --> 00:04:52,840
I wish you all the very best.