topic I don't understand, where in Network Security

How to know ASA' neighbors based on show arp ?

eigrpy — Tue, 12 Mar 2019 06:29:59 GMT

Hi In ASA55555, the output of command show arp is as following. Based on these results, how can we know its neighbor ? Thank you

inside 192.30.11.3 xxxx.xxxx.xxxx 649
inside 192.30.11.1 yyyy.yyyy.yyyy 7399
management 192.31.10.12 zzzz.zzzz.zzzz 4189

management 192.31.10.11 aaaa.aaaa.aaaa 7369

Not sure what you are asking,

jan.nielsen — Wed, 26 Aug 2015 14:07:17 GMT

Not sure what you are asking, are you talking about it's mate when running a failover pair of ASA's, or just what devices are connected to the same network as the ASA ?

"show arp" will show you all devices that are in the same ip network as the asa, that the asa has seen packets from, so anything in the arp table, is a neighbour.

Sorry that I did not make it

eigrpy — Wed, 26 Aug 2015 15:16:10 GMT

Sorry that I did not make it clearly. The ASA (FO)is connected with Nexus. Based on show arp in ASA and show ip arp and show mac address table in Nexus, can I know which port of Nexus the asa is connected with ?

On IOS based switch, the

Maykol Rojas — Wed, 26 Aug 2015 18:36:31 GMT

On IOS based switch, the command is " show mac address-table address aaa.aaa.aaa" and that would show you the port the device is connected to.

Not sure it works the same way on the Nexus.

Mike.

Ah, well on the ASA you will

jan.nielsen — Wed, 26 Aug 2015 21:37:39 GMT

Ah, well on the ASA you will need to use show interface, as the arp table does not include the ASA's own ip/mac address. show interface will give you that, and then you can use "show ip arp" or" show mac address-table" on the nexus to find the ASA's mac address and the port it is on.

asa# sh int
Interface GigabitEthernet1/1 "inside", is up, line protocol is up
Hardware is Accelerator rev01, BW 1000 Mbps, DLY 10 usec
        Auto-Duplex(Full-duplex), Auto-Speed(1000 Mbps)
        Input flow control is unsupported, output flow control is off
        MAC address a46c.2aaa.3109, MTU 1500

Yes, you are right. The Nexus

eigrpy — Thu, 27 Aug 2015 14:18:47 GMT

Yes, you are right. The Nexus and ASA can see each other's mac address, and can know the port, but when the ASA and switch3560 are linked with each other, they can not see each other's mac address. Do you think this is normal ?

I don't understand, where

jan.nielsen — Thu, 27 Aug 2015 14:41:00 GMT

I don't understand, where does the 3560 come into the picture, i thought the asa was connected to a nexus?

ASA is connected with Nexus,

eigrpy — Thu, 27 Aug 2015 14:44:31 GMT

ASA is connected with Nexus, and also with the switch3560 by management interface