Solved: EIGRP neighbor UP, routes showing but ping working only on one direction! - Page 3

mazzz · ‎10-10-2018

Hi guys,

I have my two Cisco L3 switches connected via a L2 link on which I activated EIGRP 10 and the neighborship is up.

vlan 50 : 172.17.192.128/25 --------[L3_SW_2] Fa0/24====L2====Fa1/0/48 [L3_SW_1] -------- vlan 50 : 172.17.192.0/25

The interco subnet of the L2 link is : 192.168.1.200/30

From L3_SW_2, I am able to ping an IP of the vlan 50 behind L3_SW_L1 : 172.17.192.24.

But the reverse doesn't work (I tried to ping from L3_SW_2 an IP behind SW_1 : 172.17.192.130 which desn't work).

L3_SW_2#sh ip route eigr
.... output omitted ....
Gateway of last resort is 172.17.192.210 to network 0.0.0.0

      172.17.0.0/16 is variably subnetted, 3 subnets, 2 masks
D        172.17.192.0/25
           [90/28416] via 192.168.1.201, 02:00:21, FastEthernet0/24
L3_SW_2#

L3_SW_1#sh ip eigrp neighbors
EIGRP-IPv4 Neighbors for AS(10)
H   Address                 Interface              Hold Uptime   SRTT   RTO Q Seq
                                                   (sec)         (ms)       Cnt Num
0   192.168.1.202           Fa1/0/48                 14 01:57:25    7   100 0 29
L3_SW_2#

L3_SW_2#sh ip eigrp neighbors
EIGRP-IPv4 Neighbors for AS(10)
H   Address                 Interface       Hold Uptime   SRTT   RTO Q Seq
                                            (sec)         (ms)       Cnt Num
0   192.168.1.201           Fa0/24            14 01:58:10    1   200 0 34
L3_SW_2#

L3_SW_2#sh ip arp
Protocol Address          Age (min) Hardware Addr   Type   Interface
Internet 172.17.192.130          1   000c.297e.8f75 ARPA   Vlan50
Internet 172.17.192.140          9   c81f.66d7.c878 ARPA   Vlan50
Internet 172.17.192.200          -   9caf.cad2.c0c4 ARPA   Vlan50
Internet 172.17.192.210        200   4c4e.3539.77c1 ARPA   Vlan50
Internet 192.168.1.201         121   b8be.bf9e.3b44 ARPA   FastEthernet0/24
Internet 192.168.1.202           -   9caf.cad2.c0c1 ARPA   FastEthernet0/24

L3_SW_1#sh ip arp
Protocol Address          Age (min) Hardware Addr   Type   Interface
Internet 10.170.124.121          -   b8be.bf9e.3b42 ARPA   Vlan30
Internet 10.170.124.122         22   0025.90ca.1f62 ARPA   Vlan30
Internet 172.17.192.8          160   0026.b981.a277 ARPA   Vlan50
Internet 172.17.192.9            0   0026.b981.a26f ARPA   Vlan50

L3_SW_1#sh run | s eigrp
router eigrp 10
network 172.17.192.0 0.0.0.127
network 192.168.1.200 0.0.0.3
passive-interface default
no passive-interface FastEthernet1/0/48
no passive-interface Vlan50

L3_SW_2#sh run | s eigrp
router eigrp 10
network 172.17.192.128 0.0.0.127
network 192.168.1.200 0.0.0.3
passive-interface default
no passive-interface FastEthernet0/24
no passive-interface Vlan50

I need your help on this. Please ask me if you need other command outputs.

Thank you,

mazzz · ‎10-12-2018

Hi Rick,

Unfortunately, I'ven't yet figured out the issue.

Here you have the arp table. For SW_1, I didn't put the whole ARP table (a large one).

L3_SW_L2#sh ip arp
Protocol Address          Age (min) Hardware Addr   Type   Interface
Internet 172.17.192.130          3   000c.297e.8f75 ARPA   Vlan50
Internet 172.17.192.131          1   000c.2954.6201 ARPA   Vlan50
Internet 172.17.192.132          7   000c.298e.1e50 ARPA   Vlan50
Internet 172.17.192.140         10   c81f.66d7.c878 ARPA   Vlan50
Internet 172.17.192.200          -   9caf.cad2.c0c4 ARPA   Vlan50
Internet 172.17.192.210         47   4c4e.3539.77c1 ARPA   Vlan50
Internet 192.168.1.201         240   b8be.bf9e.3b44 ARPA   FastEthernet0/24
Internet 192.168.1.202           -   9caf.cad2.c0c1 ARPA   FastEthernet0/24

L3_SW_1#sh ip arp

Protocol Address Age (min) Hardware Addr Type Interface

Internet 10.170.124.121          -   b8be.bf9e.3b42 ARPA   Vlan30
Internet 10.170.124.122          6   0025.90ca.1f62 ARPA   Vlan30
Internet 172.17.192.8           98   0026.b981.a277 ARPA   Vlan50
Internet 172.17.192.9            0   0026.b981.a26f ARPA   Vlan50
Internet 172.17.192.11          11   0026.b982.0f83 ARPA   Vlan50
Internet 172.17.192.13           0   bc30.5be2.650c ARPA   Vlan50

Internet 192.168.1.201 - b8be.bf9e.3b44 ARPA FastEthernet1/0/48
Internet 192.168.1.202 241 9caf.cad2.c0c1 ARPA FastEthernet1/0/48

....... <<<<<<<< omitted >>>>>>>> ...........

Alex Pfeil · ‎10-12-2018

what is the default gateway of 130? what type of device is it? The MAC address shows VMWare. Can you ping router to router using the source subnet of each?

Also, show ip cef "othersideIPaddress" for each side.

Please mark helpful posts.

Richard Burts · ‎10-12-2018

Please post the details of the configuration of the devices at 172.17.192.130 and 140. I am especially interested in what is their default gateway.

HTH

Rick

HTH

Rick

mazzz · ‎10-17-2018

Hi Rick,

Sorry for late reply as I was absent for a while.

The scenario even for me was a "big" strange one! I've just checked with the system guy and apparently the default route was pointing to the Operator Router, instead of the L3 VLAN IP. I made him change the GW+Mask to the VLAN 50 and it works now! Such a silly issue!

Thanks for your time and effort! 5*

Lets count on the opportunity to troubleshoot on next issue (hope it wouldn't be that silly, I'll try to give a challanging one :)

Thanks to every contributors!

Richard Burts · ‎10-17-2018

I am glad to know that the problem is resolved and that it was the gateway configured on the devices. It was puzzling that ping worked when sent through MPLS but not when it went directly. That led me to re-examine the question of default gateway. Thank you for marking this question as solved. This will help other participants in the community to identify discussions which have helpful information. These communities are excellent places to ask questions and to learn about networking. I hope to see you continue to be active in the community.

HTH

Rick

HTH

Rick

mazzz · ‎10-17-2018

mljevakovic : thanks for your efforts. Finally, the issue was with the destination servers themselve. The default gateway IP was incorrectly configured by the system guy. Appreciate your efforts of building a lab based on this issue. Keep up that good effort! :)

mljevakovic · ‎10-17-2018

you are welcome.

it is better to walk with friend through dark than alone through light