Question

Getting IP address of connected devices on 4800/4900 ERS switches

  • 10 September 2020
  • 10 replies
  • 167 views

I have a few 4800 and 4900 switches. Is it possible to get the IP address of connected devices? The only way I can get any IP address of a device is for Avaya VoIP phones using the command show lldp neighbor med inventory.


10 replies

Userlevel 4

Try "show autotopology nmm-table"

Try "show autotopology nmm-table"

 

It only shows IPs of connected switches not PCs.

Userlevel 4

To check the IPs for the end device, i guess "show lldp neighbors" would be the only way to check. You might can check the IPs using ARP table as well if that can help.

show lldp neighbors and sh mac-address-table only shows me MAC addresses. 

sh arp shows me the IP and MAC addresses of our cores which are ERS8810

Userlevel 2

It depends on the switch configuration.  For example if you are using feature called dhcp-snooping you can get the binding table.

show ip dhcp-snooping binding

But of course only for clients who are using dynamic addresses.

We normally set the dhc-snooping trusted on the trunk ports and to the PC VLAN.

ip dhcp-snooping vlan 100

interface ethernet 49-50
ip dhcp-snooping trusted

How would it affect if it is set to binding?

I noticed that in COM 3.0 I can see and search for IP devices under Routing Manager and selecting any one of our Layer 3 core switches.

Routing Manager / IPv4 Networks / IP Routing / ARP

 

I notice it shows the Interface as a number in the VLAN name. Example 4321 in PC

How can I cross reference that Interface to the switch that is connected to?

 

Userlevel 5
Badge +1

Roc156,

On your core do a “show ip arp”, you’ll get all the known IP’s with the corresponding port (switch connected)

/if they are configured with SPBM, you can run “show vlan remote-mac-table vlanid” but I’m not sur if /the ERS8810 support it.

if you do a “show mac-address-table” on the ERS you’ll get the MAC and the port.

 

MS Excel will do the rest ;)

 

Mig

SPBM is not enabled.

So I will need to do “sh ip arp” on the core and I’ll get the IP and MAC address, along with which switch it is connected to. Then I connect to the switch and run the “show mac-address-table” and search for the MAC address and I’ll be able to see the port to which it is connected.

Is that bout right?

Userlevel 5
Badge +1

SPBM is not enabled.

So I will need to do “sh ip arp” on the core and I’ll get the IP and MAC address, along with which switch it is connected to. Then I connect to the switch and run the “show mac-address-table” and search for the MAC address and I’ll be able to see the port to which it is connected.

Is that bout right?

Almost,

you can also do “show lldp neig” and “show autotop nm” do get additional info on the switches connected to the core.

Mig

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