I got one for you Darby...

Or any of you who happen to have the Technology Labs from Internetwork Expert. I am on the "Transiting NON-BGP Speaking Devices - Redistribution". The problem I am having is on R4 and R5. Apparently, I issue the "network x.x.x.x" command under their respective BGP process. But when I check to see what advertised routes are being sent to R1 & R2 respectively, it says 0.

Correct me if I'm wrong, but issuing the "network x.x.x.x" command should advertise it into BGP, and by extension, on to eBGP neighbors? When I created a loopback interface on R4 for testing purposes, then issued the above command in the BGP process, I was able to see the loopback address being advertised by BGP. So why wouldn't a connected interface be advertised as well??

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Comments

EdTheLad

Is auto-summary enabled? Should you be using the mask command along with the network statement?I dont have these tech labs so i can only guess!

wildfire

Have u got Synchornization turned on?

Have you got a matching igp route in your table to advertise out? It must be a valid one, for example to advertise 192.168.0.0 /24

create a longest match route to null 0 ip route 192.168.0.0 255.255.255.0 null 0 then issue the network 192.168.0.0 under the BGP proccess

kiddsupreme

It goes like this. R4 is in BGP AS 3. R1 is in BGP AS 2. They are eBGP neighbors.

Under R4 the configuration goes:

int e0/1
ip address 204.0.1.4 255.255.255.0
no shut

int e0/0 <---Connected to R1
ip address 155.1.146.4 255.255.255.0
no shut

router bgp 3
no synch
neighbor 155.1.146.1 remote-as 2
network 204.0.1.4 mask 255.255.255.0

Under R1 the configuration goes:

int fa0/0 <--- Connected to R4
ip address 155.1.146.1 255.255.255.0
no shut

router bgp 2
no synch
neighbor 155.1.146.4 remote-as 3

router eigrp 2
network 155.1.146.1 0.0.0.0
no auto

On R4 when you do a "show ip bgp neighbor 155.1.146.1 advertised-routes" I get nothing. However, doing a "show ip bgp summary" shows the the bgp session is up and running.

DW [banned]

BGP

kiddsupreme

It seems like my brain has gone all to mush. For the life of me I can't get basic connectivity to work, and I know it is something simple. Maybe a fresh pair of eyes can help me. Once I get this out the way, then I can test out the previous problem I had.

Like me preface by saying I'm using dynamips to lab it up. The first issue I had was with the IE3.0 cabling setup. I had to switch some things around to make it work. This time, I used the IE4.0 cabling setup to make sure I had it like the book had it. I am trying to get basic connectivity between R1 and R4. Between the two routers are two switches, SW1 & SW4. It looks something like this:

R1--(FA0/0)--><--(FA1/1)--SW1--(FA2/9 - 11)--><--(FA2/3 - 5)--SW4--(FA1/4)--> <--(E0/0)--R4

To recap R1 is connected via its FA0/0 interface to SW1's FA1/1 interface. Likewise R4 is connected to SW2 via E0/0 and FA1/4 respectively. SW1 and SW4 are connected via 3 FA connections.

The trouble I am having is getting reachability between R1 and R4. The IP address of R1's FA0/0 is 155.1.146.1 255.255.255.0. The IP address of R4's E0/0 is 155.1.146.4 255.255.255.0.

They are suppose to be in VLAN 146. Therefore I created a VTP domain "CISCO" on SW1 and made it a server. Created VLAN 146 and put interface FA1/1 (Connection to R1) in VLAN 146. I made SW4 a client in the VTP domain "CISCO" and put interface FA1/4 in VLAN 146 (Connection to R4). Then I created a trunk between SW1 and SW4 to pass traffic through.

**Configuration for SW1**
interface FastEthernet2/9
description To SW4 F2/3
switchport mode trunk
!
interface FastEthernet2/10
description To SW4 F2/4
switchport mode trunk
!
interface FastEthernet2/11
description To SW4 F2/5
switchport mode trunk

**Configuration for SW4**
interface FastEthernet2/3
description To SW1 F2/9
switchport mode trunk
!
interface FastEthernet2/4
description To SW1 F2/10
switchport mode trunk
!
interface FastEthernet2/5
description To SW1 F2/11
switchport mode trunk

**show int trunk on SW1**
Rack1SW1#sh int trunk

Port Mode Encapsulation Status Native vlan
Fa2/9 on 802.1q trunking 1
Fa2/10 on 802.1q trunking 1
Fa2/11 on 802.1q trunking 1

Port Vlans allowed on trunk
Fa2/9 1-1005
Fa2/10 1-1005
Fa2/11 1-1005

Port Vlans allowed and active in management domain
Fa2/9 1,146
Fa2/10 1,146
Fa2/11 1,146

Port Vlans in spanning tree forwarding state and not pruned
Fa2/9 1,146
Fa2/10 1,146
Fa2/11 1,146

**show int trunk on SW4**
Rack1SW4#sh int trunk

Port Mode Encapsulation Status Native vlan
Fa2/3 on 802.1q trunking 1
Fa2/4 on 802.1q trunking 1
Fa2/5 on 802.1q trunking 1

Port Vlans allowed on trunk
Fa2/3 1-1005
Fa2/4 1-1005
Fa2/5 1-1005

Port Vlans allowed and active in management domain
Fa2/3 1,146
Fa2/4 1,146
Fa2/5 1,146

Port Vlans in spanning tree forwarding state and not pruned
Fa2/3 1,146
Fa2/4 none
Fa2/5 none

****Rack1SW4#sh spanning-tree vlan 146****

VLAN146 is executing the ieee compatible Spanning Tree protocol
Bridge Identifier has priority 32768, address cc09.4e00.0001
Configured hello time 2, max age 20, forward delay 15
Current root has priority 32768, address cc06.4e0f.0001
Root port is 84 (FastEthernet2/3), cost of root path is 19
Topology change flag not set, detected flag not set
Number of topology changes 14 last change occurred 00:03:06 ago
from FastEthernet2/3
Times: hold 1, topology change 35, notification 2
hello 2, max age 20, forward delay 15
Timers: hello 0, topology change 0, notification 0, aging 0

Port 45 (FastEthernet1/4) of VLAN146 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.45.
Designated root has priority 32768, address cc06.4e0f.0001
Designated bridge has priority 32768, address cc09.4e00.0001
Designated port id is 128.45, designated path cost 19
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 1554, received 0

Port 84 (FastEthernet2/3) of VLAN146 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.84.
Designated root has priority 32768, address cc06.4e0f.0001
Designated bridge has priority 32768, address cc06.4e0f.0001
Designated port id is 128.90, designated path cost 0
Timers: message age 1, forward delay 0, hold 0
Number of transitions to forwarding state: 2
BPDU: sent 35, received 625

Port 85 (FastEthernet2/4) of VLAN146 is blocking
Port path cost 19, Port priority 128, Port Identifier 128.85.
Designated root has priority 32768, address cc06.4e0f.0001
Designated bridge has priority 32768, address cc06.4e0f.0001
Designated port id is 128.91, designated path cost 0
Timers: message age 1, forward delay 0, hold 0
Number of transitions to forwarding state: 0
BPDU: sent 33, received 584

Port 86 (FastEthernet2/5) of VLAN146 is blocking
Port path cost 19, Port priority 128, Port Identifier 128.86.
Designated root has priority 32768, address cc06.4e0f.0001
Designated bridge has priority 32768, address cc06.4e0f.0001
Designated port id is 128.92, designated path cost 0
Timers: message age 1, forward delay 0, hold 0
Number of transitions to forwarding state: 0
BPDU: sent 33, received 579

***Rack1SW1#sh spanning-tree vlan 146***

VLAN146 is executing the ieee compatible Spanning Tree protocol
Bridge Identifier has priority 32768, address cc06.4e0f.0001
Configured hello time 2, max age 20, forward delay 15
We are the root of the spanning tree
Topology change flag set, detected flag set
Number of topology changes 11 last change occurred 00:00:09 ago
from FastEthernet1/3
Times: hold 1, topology change 35, notification 2
hello 2, max age 20, forward delay 15
Timers: hello 0, topology change 25, notification 0, aging 0

Port 42 (FastEthernet1/1) of VLAN146 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.42.
Designated root has priority 32768, address cc06.4e0f.0001
Designated bridge has priority 32768, address cc06.4e0f.0001
Designated port id is 128.42, designated path cost 0
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
BPDU: sent 1636, received 0

Port 90 (FastEthernet2/9) of VLAN146 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.90.
Designated root has priority 32768, address cc06.4e0f.0001
Designated bridge has priority 32768, address cc06.4e0f.0001
Designated port id is 128.90, designated path cost 0
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 2
BPDU: sent 737, received 35

Port 91 (FastEthernet2/10) of VLAN146 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.91.
Designated root has priority 32768, address cc06.4e0f.0001
Designated bridge has priority 32768, address cc06.4e0f.0001
Designated port id is 128.91, designated path cost 0
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 2
BPDU: sent 732, received 17

Port 92 (FastEthernet2/11) of VLAN146 is forwarding
Port path cost 19, Port priority 128, Port Identifier 128.92.
Designated root has priority 32768, address cc06.4e0f.0001
Designated bridge has priority 32768, address cc06.4e0f.0001
Designated port id is 128.92, designated path cost 0
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 2
BPDU: sent 729, received 9

***Rack1SW1#sh vlan-switch***

VLAN Name Status Ports
----

1 default active Fa1/0, Fa1/2, Fa1/3, Fa1/4
Fa1/5, Fa1/6, Fa1/7, Fa1/8
Fa1/9, Fa1/10, Fa1/11, Fa1/12
Fa1/13, Fa1/14, Fa1/15, Fa2/0
Fa2/1, Fa2/2, Fa2/3, Fa2/4
Fa2/5, Fa2/6, Fa2/7, Fa2/8
Fa2/12, Fa2/13, Fa2/14, Fa2/15
146 VLAN0146 active Fa1/1
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active

***Rack1SW4#sh vlan-switch***

VLAN Name Status Ports
----

1 default active Fa1/0, Fa1/1, Fa1/2, Fa1/3
Fa1/5, Fa1/6, Fa1/7, Fa1/8
Fa1/9, Fa1/10, Fa1/11, Fa1/12
Fa1/13, Fa1/14, Fa1/15, Fa2/0
Fa2/1, Fa2/2, Fa2/6, Fa2/7
Fa2/8, Fa2/9, Fa2/10, Fa2/11
Fa2/12, Fa2/13, Fa2/14, Fa2/15
146 VLAN0146 active Fa1/4
1002 fddi-default active
1003 token-ring-default active
1004 fddinet-default active
1005 trnet-default active

******
So please tell me what silly thing I'm missing so I can start kicking myself in the butt now.

EdTheLad

I cant see any obvious problem, if i were you i would set the trunks to dynamic desirable just to see if there is an issue with the trunk.Then i would check the mac tables to see if the routers mac address is being learned by the switches in the required vlan.

mikej412

kiddsupreme wrote:

Like me preface by saying I'm using dynamips to lab it up. The first issue I had was with the IE3.0 cabling setup. I had to switch some things around to make it work. This time, I used the IE4.0 cabling setup to make sure I had it like the book had it. I am trying to get basic connectivity between R1 and R4. Between the two routers are two switches, SW1 & SW4.

By basic connectivity you mean you can't ping between R1 and R4?

Since you mentioned you're using dynamips and you have 2 switches and are showing switch output -- are you using the a couple of emulated routers with NM-16ESW modules as your switches? I haven't tried it with the Feb 18th Dynagen/Dynamips but there were lots of layer 2 issues with the previous Dynagen/Dynamips when I tried simple switching configurations using the NM-16ESW modules -- the "hardware simulation" seems to need some work still.

kiddsupreme

mikej412 wrote:

By basic connectivity you mean you can't ping between R1 and R4?

Since you mentioned you're using dynamips and you have 2 switches and are showing switch output -- are you using the a couple of emulated routers with NM-16ESW modules as your switches? I haven't tried it with the Feb 18th Dynagen/Dynamips but there were lots of layer 2 issues with the previous Dynagen/Dynamips when I tried simple switching configurations using the NM-16ESW modules -- the "hardware simulation" seems to need some work still.

Yes, I cannot ping between R1 and R4. Everything is emulated. And this is the latest (Feb 18th) build of Dynamips. What I find interesting is if both routers (Say R1 and R3) are connected directly to the same switch, I have no issue in pinging between the two routers. But put the two 'switches' in the middle, and it doesn't want to work.

mikej412

kiddsupreme wrote:

What I find interesting is if both routers (Say R1 and R3) are connected directly to the same switch, I have no issue in pinging between the two routers. But put the two 'switches' in the middle, and it doesn't want to work.

Right -- those are the some of the "layer 2 issues."

Call it a Dynamips (and/or Dynagen) bug (or unfinished implementation) and try the "single switch work around." Once you're pinging, you can get back to the fun BGP issues.

DW [banned]

Good

kiddsupreme

Success! I think I found out what the issue was before. Below are the configurations of each device. My first issue was I forgot what BGP does...passes prefix information from neighbor to neighbor. I think I originally issued the command "network 204.12.1.4 mask 255.255.255.255" on R4 instead of "network 204.12.1.0". I also made the same mistake on R5. Instead of putting "network 155.1.5.0 mask 255.255.255.0" I put "network 155.1.5.5".

The second I issue I had after resolving that was although I was seeing the route in R1 (for R4's network statement) and R2 (for R5's network statement), I couldn't ping those networks on R3. I forgot I needed to make a static route to R1 & R2 respectively in relationship to R4 and R5. Although the ping requests were getting to R4 and R5, they didn't know how to route the icmp request back. The static route took care of that.

**R1 Config**

interface FastEthernet0/0
ip address 155.1.146.1 255.255.255.0
speed 100
full-duplex
!
interface Serial1/1
ip address 155.1.13.1 255.255.255.0
serial restart-delay 0
no dce-terminal-timing-enable
!
router eigrp 2
redistribute bgp 2 metric 1 1 1 1 1 route-map BGP2IGP
network 155.1.13.1 0.0.0.0
no auto-summary
!
router bgp 2
no synchronization
bgp log-neighbor-changes
neighbor 155.1.23.2 remote-as 2
neighbor 155.1.146.4 remote-as 3
no auto-summary
!
!
ip prefix-list VLAN146 seq 5 permit 204.12.1.0/24
!
route-map BGP2IGP permit 10
match ip address prefix-list VLAN146

**R2 Config**
!
interface Serial1/0
ip address 155.1.0.2 255.255.255.0
encapsulation frame-relay
serial restart-delay 0
no dce-terminal-timing-enable
frame-relay map ip 155.1.0.5 205 broadcast
no frame-relay inverse-arp
!
interface Serial1/1
ip address 155.1.23.2 255.255.255.0
serial restart-delay 0
no dce-terminal-timing-enable
!!
router eigrp 2
redistribute bgp 2 metric 1 1 1 1 1 route-map BGP2IGP
network 155.1.23.2 0.0.0.0
no auto-summary
!
router bgp 2
no synchronization
bgp log-neighbor-changes
neighbor 155.1.0.5 remote-as 1
neighbor 155.1.13.1 remote-as 2
no auto-summary
!
!
ip prefix-list VLAN5 seq 5 permit 155.1.5.0/24
!
route-map BGP2IGP permit 10
match ip address prefix-list VLAN5

**R3 Config**
!
interface Serial1/2
ip address 155.1.13.3 255.255.255.0
serial restart-delay 0
clockrate 64000
no dce-terminal-timing-enable
!
interface Serial1/3
ip address 155.1.23.3 255.255.255.0
serial restart-delay 0
clockrate 64000
no dce-terminal-timing-enable
!
router eigrp 2
network 155.1.13.3 0.0.0.0
network 155.1.23.3 0.0.0.0
no auto-summary

**R4 Config**
!
!
interface Ethernet0/0
ip address 155.1.146.4 255.255.255.0
full-duplex
!
interface Ethernet0/1
ip address 204.12.1.4 255.255.255.0
full-duplex
!
router bgp 3
no synchronization
bgp log-neighbor-changes
network 204.12.1.0
network 204.12.1.4
neighbor 155.1.146.1 remote-as 2
no auto-summary
!
ip route 0.0.0.0 0.0.0.0 155.1.146.1

**R5 Config**
!
interface Ethernet0/1
ip address 155.1.5.5 255.255.255.0
full-duplex
!
interface Serial1/0
ip address 155.1.0.5 255.255.255.0
encapsulation frame-relay
serial restart-delay 0
no dce-terminal-timing-enable
frame-relay map ip 155.1.0.2 502 broadcast
no frame-relay inverse-arp
!
router bgp 1
no synchronization
bgp log-neighbor-changes
network 155.1.5.0 mask 255.255.255.0
neighbor 155.1.0.2 remote-as 2
no auto-summary
ip route 0.0.0.0 0.0.0.0 155.1.0.2

**Rack1R1#sh ip route**

Gateway of last resort is not set

B 204.12.1.0/24 [20/0] via 155.1.146.4, 00:48:54
155.1.0.0/24 is subnetted, 4 subnets
C 155.1.146.0 is directly connected, FastEthernet0/0
D 155.1.23.0 [90/2681856] via 155.1.13.3, 00:22:59, Serial1/1
C 155.1.13.0 is directly connected, Serial1/1
D EX 155.1.5.0 [170/2561024256] via 155.1.13.3, 00:22:59, Serial1/1

**Rack1R2#sh ip route**

Gateway of last resort is not set

D EX 204.12.1.0/24 [170/2561024256] via 155.1.23.3, 00:23:31, Serial1/1
155.1.0.0/24 is subnetted, 4 subnets
C 155.1.23.0 is directly connected, Serial1/1
D 155.1.13.0 [90/2681856] via 155.1.23.3, 01:00:20, Serial1/1
C 155.1.0.0 is directly connected, Serial1/0
B 155.1.5.0 [20/0] via 155.1.0.5, 00:47:59

**Rack1R3#sh ip route**

Gateway of last resort is not set

D EX 204.12.1.0/24 [170/2560512256] via 155.1.13.1, 00:24:03, Serial1/2
155.1.0.0/24 is subnetted, 3 subnets
C 155.1.23.0 is directly connected, Serial1/3
C 155.1.13.0 is directly connected, Serial1/2
D EX 155.1.5.0 [170/2560512256] via 155.1.23.2, 00:39:14, Serial1/3

**Rack1R4#sh ip route**

Gateway of last resort is 155.1.146.1 to network 0.0.0.0

C 204.12.1.0/24 is directly connected, Ethernet0/1
155.1.0.0/24 is subnetted, 1 subnets
C 155.1.146.0 is directly connected, Ethernet0/0
S* 0.0.0.0/0 [1/0] via 155.1.146.1

**Rack1R5#sh ip route**

Gateway of last resort is 155.1.0.2 to network 0.0.0.0

155.1.0.0/24 is subnetted, 2 subnets
C 155.1.0.0 is directly connected, Serial1/0
C 155.1.5.0 is directly connected, Ethernet0/1
S* 0.0.0.0/0 [1/0] via 155.1.0.2

mikej412

kiddsupreme wrote:

The static route took care of that.

Hum.... but the odds of being allowed to use static routes on the lab exam are probably slim to none. The R1 to R4 ethernet (if there are no loopback -- update source -- multi-hop issues) screams out for a next-hop-self. Double check BGPs handling of the the next hop value for the the multiple-access broadcast ethernet network. Also check for the Frame-Relay between R2 & R5.....

Did you do the no synchronization? If R1 and R2 are iBGP peers and you're doing redistribution from BGP to EIGRP.... synchronization should be okay.

kiddsupreme

mikej412 wrote:

Hum.... but the odds of being allowed to use static routes on the lab exam are probably slim to none. The R1 to R4 ethernet (if there are no loopback -- update source -- multi-hop issues) screams out for a next-hop-self. Double check BGPs handling of the the next hop value for the the multiple-access broadcast ethernet network. Also check for the Frame-Relay between R2 & R5.....

Did you do the no synchronization? If R1 and R2 are iBGP peers and you're doing redistribution from BGP to EIGRP.... synchronization should be okay.

LOL, you know how to bring a guy down. Just kidding. But now that you say that, you're probably right. They aren't going to let me get off easy like that with a static route. I will have to wait until I get off of work to reconfigure it all and see if a next-hop-self (in this particular scenario, there were no loopbacks used or update-source) will do the trick. Thanks again Mike

kiddsupreme

Finally got around to resetting this lab up again. I think the problem I was having before was that from R3, I couldn't ping R4's E0/1 address or R5 E0/1 address. But, I was able to do what the lab wanted me to do: Ping from the E0/1 interface on R4 all the way to the E0/1 interface on R5. No need for static routes on R4 and R5. I did make sure this time though to make sure the neighbor relationship between R1 & R2 also included the statement 'next-hop-self' to make sure the routes they were receiving from R4 and R5 respectively showed up as the best routes.