Posted on May 13, 2019 6:23 pm
 |  Asked by Nilesh Bhadane
 |  84 views
0
0
Print Friendly, PDF & Email

Hi,

Consider I have 2 arista devices A & B
A & B are connected with phyiscal interface.

I logged in to A device & I know the ip adress on connected physical interfcae end.
How to find from machine A what is the IP address of other physical interface end which is connected to device B.

Thanks,
Nilesh

I would try sh arp interface
This will list all IPs and MAC addresses present on the other side of the link.

Thx
Patrik

(Patrik Olsson Olsson at May 15, 2019 8:52 am)
0
Posted by Kishore Sukumaran
Answered on May 14, 2019 11:05 am

Hello Nilesh,

Thanks for the question. From what you have asked I see A & B are directly connected with physical interface.

In which case you can use the command “show lldp neighbors detail” on device A to view the Ip address of the physical interface end which is connected to device B.

For example:

In my case [vEOS1 (et1 – 192.168.1.2)] < --------> [(et1 – 192.168.1.3) vEOS2] is the topology. Below is the result:

=============================================================
vEOS1#show lldp neighbors detail
Interface Ethernet1 detected 1 LLDP neighbors:

Neighbor 5012.007b.e9f5/”Ethernet1″, age 21 seconds
Discovered 0:13:30 ago; Last changed 0:11:50 ago
– Chassis ID type: MAC address (4)
Chassis ID : 5012.007b.e9f5
– Port ID type: Interface name(5)
Port ID : “Ethernet1”
– Time To Live: 120 seconds
– System Name: “vEOS2”
– System Description: “Arista Networks EOS version 4.21.4F running on a vEOS”
– System Capabilities : Bridge, Router
Enabled Capabilities: Bridge
– Management Address Subtype: IPv4

Management Address : 192.168.1.3

Interface Number Subtype : ifIndex (2)
Interface Number : 1
OID String :
– IEEE802.1 Port VLAN ID: 0
– IEEE802.1/IEEE802.3 Link Aggregation
Link Aggregation Status: Capable, Disabled (0x01)
Port ID : 0
– IEEE802.3 Maximum Frame Size: 9236 bytes

Interface Ethernet2 detected 0 LLDP neighbors:

Interface Ethernet3 detected 0 LLDP neighbors:

Interface Management1 detected 0 LLDP neighbors:
=============================================================

Hope this helped. Thanks!

Kishore

Hello Nilesh,

Following on this one. Apologies, the above answer that I posted could be misleading. It was based on a virtual lab test.

“show lldp neighbors detail” will actually not show you the IP address of the remote end connected interface. The IP that is seen on the management address is the IP of the remote end device Management interface. Or if there is a loopback interface configured, management address shows the IP address of the loopback interface.

I am still working on the other possible ways of determining the IP address of the remote end connected interface. I will post it here once I find the way

Kishore

(Kishore Sukumaran at May 16, 2019 12:06 pm)

Post your Answer

You must be logged in to post an answer.