What caused the accidental advertisement of internal networks to your EBGP peer?

— Exhibit —
user@router> show configuration routing-options autonomous-system
65550;
user@router> show configuration protocols bgp
group ibgp {
type internal;
neighbor 10.0.3.5;
}
group ibgpv6 {
type internal;
local-address 2001:ffff::3:4;
neighbor 2001:ffff::3:5;
}
group as65010 {
family inet {
unicast;

}
family inet6 {
unicast;
}
export as65010-out;
peer-as 65010;
neighbor 172.16.0.6;
}
user@router> show configuration policy-options
policy-statement as65010-out {
term locally-originated {
from as-path local-only;
then {
metric 7000;
}
term from-as65222 {
from as-path as65222-orig;
then as-path-prepend “65550 65550 65550 65550”;
}
term transit-as701 {
from as-path transit-as701;
then {
metric 6;
}

then accept;
}
as-path local-only “(.*)”;
as-path as65222-orig “.* 65222”;
as-path transit-as701 “.* 701 .*”;
user@router> show route advertising-protocol bgp 172.16.0.6
inet.0: 43 destinations, 47 routes (43 active, 0 holddown, 0 hidden)
Prefix Nexthop MED Lclpref AS path
* 10.0.2.0/30 Self 7000 I
* 10.0.2.4/30 Self 7000 I
* 10.0.2.8/30 Self 7000 I
* 10.0.2.16/30 Self 7000 I
* 10.0.3.3/32 Self 7000 I
* 10.0.3.4/32 Self 7000 I
* 10.0.3.5/32 Self 7000 I
* 10.0.4.8/30 Self 7000 I
* 10.0.8.8/30 Self 7000 I
* 10.0.9.9/32 Self 7000 I
* 10.255.255.1/32 Self 7000 I
* 64.142.88.0/24 Self 7000 I
* 130.130.0.0/16 Self 6 65222 46375 701 14203 I
* 131.131.131.0/24 Self 6 65222 46375 701 14203 I
* 132.132.0.0/25 Self 6 65222 46375 701 32934 I
* 133.133.0.0/25 Self 6 65222 46375 701 32934 I
* 134.134.0.0/25 Self 65222 46375 14203 I
* 135.135.0.0/25 Self 65222 46375 14203 14203 I

* 172.16.0.4/30 Self 7000 I
* 172.16.0.12/30 Self 7000 I
* 172.16.200.0/30 172.16.0.6 7000 I
* 192.0.2.0/24 172.16.0.6 7000 I
* 192.168.50.0/24 Self 7000 I
* 192.168.253.0/24 Self 7000 I
* 200.200.0.0/16 172.16.0.6 7000 I
* 200.200.0.1/32 172.16.0.6 7000 I
* 200.200.1.1/32 172.16.0.6 7000 I
* 200.200.200.200/32 172.16.0.6 7000 I
inet6.0: 23 destinations, 28 routes (23 active, 0 holddown, 0 hidden)
Prefix Nexthop MED Lclpref AS path
* ::172.16.0.4/126 Self 7000 I
* 2001:1:1::/64 Self 7000 I
* 2001:1:2::/64 Self 7000 I
* 2001:ffff::3:3/128 Self 7000 I
* 2001:ffff::3:4/128 Self 7000 I
* 2001:ffff::3:5/128 Self 7000 I
* 2001:ffff::9:7/128 Self 7000 I
user@router>
— Exhibit —
Click the Exhibit button.
You are configuring an EBGP peer in a transit environment. You must advertise routes learned
from other EBGP peers in your AS. Any routes originated from within your AS should have a MED
of 7000 set. Any routes that originate in AS65222 should be prepended four times. Any routes that
transit AS701 should have a MED set to 6. This scenario results in the unintended advertisement
of internal 10.0.0.0/8 networks to your peer.

What caused the accidental advertisement of internal networks to your EBGP peer?

— Exhibit —
user@router> show configuration routing-options autonomous-system
65550;
user@router> show configuration protocols bgp
group ibgp {
type internal;
neighbor 10.0.3.5;
}
group ibgpv6 {
type internal;
local-address 2001:ffff::3:4;
neighbor 2001:ffff::3:5;
}
group as65010 {
family inet {
unicast;

}
family inet6 {
unicast;
}
export as65010-out;
peer-as 65010;
neighbor 172.16.0.6;
}
user@router> show configuration policy-options
policy-statement as65010-out {
term locally-originated {
from as-path local-only;
then {
metric 7000;
}
term from-as65222 {
from as-path as65222-orig;
then as-path-prepend “65550 65550 65550 65550”;
}
term transit-as701 {
from as-path transit-as701;
then {
metric 6;
}

then accept;
}
as-path local-only “(.*)”;
as-path as65222-orig “.* 65222”;
as-path transit-as701 “.* 701 .*”;
user@router> show route advertising-protocol bgp 172.16.0.6
inet.0: 43 destinations, 47 routes (43 active, 0 holddown, 0 hidden)
Prefix Nexthop MED Lclpref AS path
* 10.0.2.0/30 Self 7000 I
* 10.0.2.4/30 Self 7000 I
* 10.0.2.8/30 Self 7000 I
* 10.0.2.16/30 Self 7000 I
* 10.0.3.3/32 Self 7000 I
* 10.0.3.4/32 Self 7000 I
* 10.0.3.5/32 Self 7000 I
* 10.0.4.8/30 Self 7000 I
* 10.0.8.8/30 Self 7000 I
* 10.0.9.9/32 Self 7000 I
* 10.255.255.1/32 Self 7000 I
* 64.142.88.0/24 Self 7000 I
* 130.130.0.0/16 Self 6 65222 46375 701 14203 I
* 131.131.131.0/24 Self 6 65222 46375 701 14203 I
* 132.132.0.0/25 Self 6 65222 46375 701 32934 I
* 133.133.0.0/25 Self 6 65222 46375 701 32934 I
* 134.134.0.0/25 Self 65222 46375 14203 I
* 135.135.0.0/25 Self 65222 46375 14203 14203 I

* 172.16.0.4/30 Self 7000 I
* 172.16.0.12/30 Self 7000 I
* 172.16.200.0/30 172.16.0.6 7000 I
* 192.0.2.0/24 172.16.0.6 7000 I
* 192.168.50.0/24 Self 7000 I
* 192.168.253.0/24 Self 7000 I
* 200.200.0.0/16 172.16.0.6 7000 I
* 200.200.0.1/32 172.16.0.6 7000 I
* 200.200.1.1/32 172.16.0.6 7000 I
* 200.200.200.200/32 172.16.0.6 7000 I
inet6.0: 23 destinations, 28 routes (23 active, 0 holddown, 0 hidden)
Prefix Nexthop MED Lclpref AS path
* ::172.16.0.4/126 Self 7000 I
* 2001:1:1::/64 Self 7000 I
* 2001:1:2::/64 Self 7000 I
* 2001:ffff::3:3/128 Self 7000 I
* 2001:ffff::3:4/128 Self 7000 I
* 2001:ffff::3:5/128 Self 7000 I
* 2001:ffff::9:7/128 Self 7000 I
user@router>
— Exhibit —
Click the Exhibit button.
You are configuring an EBGP peer in a transit environment. You must advertise routes learned
from other EBGP peers in your AS. Any routes originated from within your AS should have a MED
of 7000 set. Any routes that originate in AS65222 should be prepended four times. Any routes that
transit AS701 should have a MED set to 6. This scenario results in the unintended advertisement
of internal 10.0.0.0/8 networks to your peer.

What caused the accidental advertisement of internal networks to your EBGP peer?

A.
Your AS number of 65550 is a private AS number.

B.
The BGP group as65010 is configured for both family inet unicast and family inet6 unicast
protocol families.

C.
The export policy as65010-out is misconfigured.

D.
The as-path local-only includes a misconfigured regular expression.



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