Feedback for INE - Mock Lab 1 TS - Ticket 7

Hi there,

Just got the result back from my Mock Lab 1 attempt. I got a fail on Ticket 7, but I am not sure I deserve it, obviously :D

Ticket 7 explicitly states : "When the issue is resolved, R2 should be able to ping R3’s Loopback0 interface source packets off its Loopback0 interface."

The SG fixes the ipv6 address issue on the frame-relay interface and the frame-relay mapping problem, however it is not necessary to fix the ipv6 address problem, and since the Do’s and Don’ts clearly states "Do not change or add any IP addresses from the initial configuration unless required for troubleshooting." I believe the solution given by the SG, though a working solution, actually breaks the TS lab rules.

I tested it again and with static routing over a frame-relay network it is not necessary for the 2 endpoints to be on the same subnet !

 

Here is the config in my test network (R1 and R5 are connected through a frame-relay switch) :

 

Rack1R1#sh run int s0/0
interface Serial0/0
 no ip address
 encapsulation frame-relay
 ipv6 address 2001:155:1:15::1/64
 clock rate 2000000
 frame-relay map ipv6 2001:155:1:51::5 105 broadcast
end

Rack1R1#sh ipv6 route
IPv6 Routing Table - 6 entries
Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP
       U - Per-user Static route, M - MIPv6
       I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary
       O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
       ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
       D - EIGRP, EX - EIGRP external
C   2001:150:1:1::/64 [0/0]
     via ::, Loopback100
L   2001:150:1:1::1/128 [0/0]
     via ::, Loopback100
S   2001:150:1:5::/64 [1/0]
     via 2001:155:1:51::5, Serial0/0
C   2001:155:1:15::/64 [0/0]
     via ::, Serial0/0
L   2001:155:1:15::1/128 [0/0]
     via ::, Serial0/0
L   FF00::/8 [0/0]
     via ::, Null0
Rack1R1#

 

Rack1R5#sh run int s0/0
interface Serial0/0
 encapsulation frame-relay
 ipv6 address 2001:155:1:51::5/64
 frame-relay map ipv6 2001:155:1:15::1 501 broadcast
end

Rack1R5#sh ipv6 route
IPv6 Routing Table - 6 entries
Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP
       U - Per-user Static route, M - MIPv6
       I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary
       O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2
       ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2
       D - EIGRP, EX - EIGRP external
S   2001:150:1:1::/64 [1/0]
     via 2001:155:1:15::1, Serial0/0
C   2001:150:1:5::/64 [0/0]
     via ::, Loopback100
L   2001:150:1:5::5/128 [0/0]
     via ::, Loopback100
C   2001:155:1:51::/64 [0/0]
     via ::, Serial0/0
L   2001:155:1:51::5/128 [0/0]
     via ::, Serial0/0
L   FF00::/8 [0/0]
     via ::, Null0
Rack1R5#

 

 

Rack1R1#debug frame-relay packet
Rack1R1#debug ipv6 packet

 

Rack1R1#ping 2001:150:1:5::5 source loop100 re 1

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 2001:150:1:5::5, timeout is 2 seconds:
Packet sent with a source address of 2001:150:1:1::1
!
Success rate is 100 percent (1/1), round-trip min/avg/max = 0/0/0 ms
Rack1R1#
*Mar  1 03:01:42.343: IPv6: SAS picked source 2001:150:1:1::1 for 2001:150:1:5::5 (Loopback100)
*Mar  1 03:01:42.343: IPv6: nexthop 2001:155:1:51::5,
*Mar  1 03:01:42.343: IPV6: source 2001:150:1:1::1 (local)
*Mar  1 03:01:42.343:       dest 2001:150:1:5::5 (Serial0/0)
*Mar  1 03:01:42.343:       traffic class 0, flow 0x0, len 100+0, prot 58, hops 64, originating
*Mar  1 03:01:42.347: Serial0/0(o): dlci 105(0x1891), pkt type 0x86DD(IPV6), datagramsize 104
*Mar  1 03:01:42.347: IPv6: Sending on Serial0/0
*Mar  1 03:01:42.347: Serial0/0(i): dlci 105(0x1891), pkt type 0x86DD, datagramsize 104
*Mar  1 03:01:42.347: IPV6: source 2001:150:1:5::5 (Serial0/0)
Rack1R1#
*Mar  1 03:01:42.347:       dest 2001:150:1:1::1
*Mar  1 03:01:42.347:       traffic class 0, flow 0x0, len 100+4, prot 58, hops 64, forward to ulp
Rack1R1#
*Mar  1 03:02:00.391: Serial0/0(i): dlci 105(0x1891), pkt type 0x800, datagramsize 80
Rack1R1#
*Mar  1 03:02:27.987: Serial0/0(i): dlci 105(0x1891), pkt type 0x800, datagramsize 80
Rack1R1#

Even though the next-hop is not known in the ipv6 RIB, there is a layer 2 mapping for it, and the way IOS is coded it still works.

 

So I think the task wording should be modified, or the solution of only fixing the frame-relay mapping statement be an acceptable solution too.

Cheers.

 

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