1
00:00:00,000 --> 00:00:03,283
[AUDIO LOG]

2
00:00:03,283 --> 00:00:07,040

3
00:00:07,040 --> 00:00:12,680
So finally, let's finish
up with the Total NSSA.

4
00:00:12,680 --> 00:00:18,590
Now, the Total NSSA is much like
the Total Stub in that, again,

5
00:00:18,590 --> 00:00:22,100
we're just going to be filtering
out the additional Type 3

6
00:00:22,100 --> 00:00:24,780
LSAs that are normally
coming into the area.

7
00:00:24,780 --> 00:00:27,780
So from that perspective,
it's about the same.

8
00:00:27,780 --> 00:00:31,880
Now, one thing that's going to
change between the normal NSSA

9
00:00:31,880 --> 00:00:34,880
is that
default-information-originate

10
00:00:34,880 --> 00:00:40,670
we were doing is now going to
be overridden by the no-summary,

11
00:00:40,670 --> 00:00:43,160
which makes it the Total NSSA.

12
00:00:43,160 --> 00:00:46,580
And it's going to
send in a Type 3 LSA.

13
00:00:46,580 --> 00:00:48,900
So let's jump in
and get started.

14
00:00:48,900 --> 00:00:52,010
We'll start looking at the
routing table on router 5

15
00:00:52,010 --> 00:00:56,230
and then we'll convert
this to a Total NSSA.

16
00:00:56,230 --> 00:01:00,490
So remember that router
5 is inside the NSSA,

17
00:01:00,490 --> 00:01:03,160
so when we do our
show ip router ospf,

18
00:01:03,160 --> 00:01:06,610
what we're really looking for
is the fact that we're getting

19
00:01:06,610 --> 00:01:09,310
all of these O IA routes.

20
00:01:09,310 --> 00:01:13,060
Also as a reminder, notice
our default is coming

21
00:01:13,060 --> 00:01:16,420
in as an N2, so a Type 7.

22
00:01:16,420 --> 00:01:20,290
Now let's convert
this to a Total NSSA.

23
00:01:20,290 --> 00:01:22,300
We'll start on router 1.

24
00:01:22,300 --> 00:01:24,880
So we're going to router ospf 1.

25
00:01:24,880 --> 00:01:29,110
And again, for area
100 after our nssa,

26
00:01:29,110 --> 00:01:34,060
we simply add no-summary
just like we do for the Stub.

27
00:01:34,060 --> 00:01:36,850
And this makes it a Total NSSA.

28
00:01:36,850 --> 00:01:40,360
We'll commit that change, and
let's go look at router 5.

29
00:01:40,360 --> 00:01:43,780
So once again, if we look at
the routing table on router 5,

30
00:01:43,780 --> 00:01:45,500
there's two things to note here.

31
00:01:45,500 --> 00:01:49,300
First, we're still getting
all the Type 3 LSAs,

32
00:01:49,300 --> 00:01:52,150
but if we look at
their next hops,

33
00:01:52,150 --> 00:01:55,630
they're all headed
towards router 4, which

34
00:01:55,630 --> 00:01:57,910
would be down towards router 3.

35
00:01:57,910 --> 00:02:01,750
So these are the O IA routes
coming in from router 3

36
00:02:01,750 --> 00:02:07,390
because we haven't converted
router 3 to Total NSSA yet.

37
00:02:07,390 --> 00:02:13,540
Also note that the default is
now an O IA or a type 3 LSA.

38
00:02:13,540 --> 00:02:16,700
Now, let's go ahead and
convert router as well.

39
00:02:16,700 --> 00:02:18,920
Again, router 3 is
the same configuration

40
00:02:18,920 --> 00:02:20,710
so we'll simply paste
it in, and we'll

41
00:02:20,710 --> 00:02:22,720
go back to router 5 to verify.

42
00:02:22,720 --> 00:02:24,860
We do our show ip
router ospf again.

43
00:02:24,860 --> 00:02:27,670
We'll see that all we have
are the O routes which

44
00:02:27,670 --> 00:02:31,720
are internal to this area, the
N2s, which are of course coming

45
00:02:31,720 --> 00:02:34,930
from router 2, and
our EIGRP environment,

46
00:02:34,930 --> 00:02:40,120
and then we have our Type 3
LSA coming in as our default.

47
00:02:40,120 --> 00:02:42,970
Just as a quick note
here, the reason

48
00:02:42,970 --> 00:02:45,820
the LSA type changes
on the default

49
00:02:45,820 --> 00:02:51,760
is we can no longer allow you
to follow an external default

50
00:02:51,760 --> 00:02:55,930
route like we could
in the normal NSSA.

51
00:02:55,930 --> 00:03:00,340
That's because we're actually
hiding OSPF information here.

52
00:03:00,340 --> 00:03:04,870
You don't have all of
the internal OSPF routes.

53
00:03:04,870 --> 00:03:07,720
And because of that,
it really needs

54
00:03:07,720 --> 00:03:11,140
to force you to default
route to the ABR.

55
00:03:11,140 --> 00:03:16,150
So this difference in Lisa
type between a normal NSSA

56
00:03:16,150 --> 00:03:18,340
doing a
default-information-originate

57
00:03:18,340 --> 00:03:22,900
and the Total NSSA
doing the Type 3,

58
00:03:22,900 --> 00:03:27,910
this is absolutely done to
prevent loops and inadvertently

59
00:03:27,910 --> 00:03:31,570
following a default out
of the OSPF environment

60
00:03:31,570 --> 00:03:35,680
when in fact the route
is internal to OSPF.

61
00:03:35,680 --> 00:03:37,720
Now there is sort of
one other minor issue

62
00:03:37,720 --> 00:03:40,840
we should address here just
because it's another NSSA

63
00:03:40,840 --> 00:03:42,400
option we haven't looked at.

64
00:03:42,400 --> 00:03:45,910
Let's go over to router 1 and
configure it to redistribute

65
00:03:45,910 --> 00:03:49,580
an interface into OSPF.

66
00:03:49,580 --> 00:03:52,990
So here we'll make an
interface loopback 100.

67
00:03:52,990 --> 00:03:58,000
We'll simply make that
IP address 101.1.1.1/24.

68
00:03:58,000 --> 00:04:00,920
We'll bring that interface up.

69
00:04:00,920 --> 00:04:03,440
We're going to
route out of ospf 1.

70
00:04:03,440 --> 00:04:06,980
And we will say to redistribute
connected routes, which

71
00:04:06,980 --> 00:04:10,000
will bring in that loopback.

72
00:04:10,000 --> 00:04:11,360
Commit our changes.

73
00:04:11,360 --> 00:04:13,780
Now, we should see
this route on router 5,

74
00:04:13,780 --> 00:04:15,410
which is sort of interesting.

75
00:04:15,410 --> 00:04:16,610
Let's go check it out.

76
00:04:16,610 --> 00:04:19,060
Notice if I look at my
routing table again,

77
00:04:19,060 --> 00:04:24,370
now I've got that 100.1.1.0/24.

78
00:04:24,370 --> 00:04:26,380
Now there's nothing
necessarily wrong

79
00:04:26,380 --> 00:04:31,400
with that except we're already
getting a default. In fact,

80
00:04:31,400 --> 00:04:33,700
we're getting a
default from router 1.

81
00:04:33,700 --> 00:04:36,970
So there's no point in following
a specific route towards router

82
00:04:36,970 --> 00:04:39,980
1 when we already
have a default.

83
00:04:39,980 --> 00:04:45,850
So if we don't want the
ASBR that is also the ABR

84
00:04:45,850 --> 00:04:49,660
to redistribute this
into the NSSA itself,

85
00:04:49,660 --> 00:04:52,160
we have to actually
turn that off.

86
00:04:52,160 --> 00:04:54,100
Let's go back over
to router 1, and what

87
00:04:54,100 --> 00:04:58,940
we need to do is on the end of
our area 100 nssa no-summary,

88
00:04:58,940 --> 00:05:01,370
we need to add
no-redistribution.

89
00:05:01,370 --> 00:05:03,920

90
00:05:03,920 --> 00:05:05,520
We'll commit those changes.

91
00:05:05,520 --> 00:05:07,190
And let's go back to router 5.

92
00:05:07,190 --> 00:05:09,770
If we do our show
ip router ospf,

93
00:05:09,770 --> 00:05:12,740
notice that that
100 network is now

94
00:05:12,740 --> 00:05:15,680
gone and we would just
follow the default.

95
00:05:15,680 --> 00:05:17,910
And just to make sure
everything's working,

96
00:05:17,910 --> 00:05:21,240
we should be able to ping
that address, we have success,

97
00:05:21,240 --> 00:05:24,830
so this is just going to follow
the default to get there.

98
00:05:24,830 --> 00:05:30,100
So in this video, we saw how
to configure the Total NSSA.

99
00:05:30,100 --> 00:05:32,770
And as you probably
noticed, it's

100
00:05:32,770 --> 00:05:35,440
configured in exactly
the same fashion

101
00:05:35,440 --> 00:05:37,690
as we configure the Total Stub.

102
00:05:37,690 --> 00:05:44,860
We simply add no-summary to the
end of the either NSSA or Stub

103
00:05:44,860 --> 00:05:45,790
command.

104
00:05:45,790 --> 00:05:49,450
We also took a look at what the
no-redistribution command does

105
00:05:49,450 --> 00:05:54,940
to prevent an ASBR that is
also an ABR from sending

106
00:05:54,940 --> 00:05:58,180
those routes into the NSSA.

107
00:05:58,180 --> 00:06:01,300
This of course, is
most useful when

108
00:06:01,300 --> 00:06:03,400
you're doing the
default-originate

109
00:06:03,400 --> 00:06:07,090
or when you're doing
the Total NSSA.

110
00:06:07,090 --> 00:06:09,190
I hope this has been
informative for you

111
00:06:09,190 --> 00:06:12,270
and I'd like to thank
you for viewing.

112
00:06:12,270 --> 00:06:15,000