APIC not discovering hosts in campus environment

[Kevin Mckenzie]

After performing a discovery on my network, I noticed that a significant quantity of my hosts were missing from the host inventory.  I decided to do a discover on a small portion of my network and received the following:

As you can see the discovery is finding many hosts, however they are NOT showing up in the host inventory.   I should note that currently ip device tracking is turned off due to an issue experienced windows hosts several years ago.  It appears that APIC-EM is able to find them durning discovery and is not adding them to the inventory.

[ngoldwat]

Your screen shot indicates that the devices are failing SNMP.  Do you have SNMP running?  ACLs?

[Kevin Mckenzie]

Nicholas

i am attempting to discover the end-hosts not switches/routers so snmp would naturally fail for them.  It sounds like IP device tracking is required for apic-em. 

Everyone

In this white paper it indicates the IP device tracking is turned on by default during discovery.    http://www.cisco.com/c/en/us/td/docs/cloud-systems-management/application-policy-infrastructure-controller-enterprise-mo…

In this case my assumption this has failed on many of my switches due to an ios version issue.  Are there any other reasons why this would fail?  Any suggestions for working around this?  Could I manually enable ip device-tracking?  An iOS upgrade to my environment would be an act of congress.

• IP Device Tracking (IPDT)—IPDT is enabled automatically for all devices by the controller. For this configuration, privileges must be given to the controller during discovery.

[yawming]

I remembered that somewhere I read a while ago - SNMP traps can be used for wireless host discovery. Can some one please confirm this ?

[aradford]

Correct. Good point are we talking wired or wireless here?

[Kevin Mckenzie]

The issue I was attempting to solve was for wired hosts.  I havent tested yet but I believe IP device tracking is my missing piece.  I will report back once I am able to test. 

[aradford]

That would be the issue.  You need IP device tracking for wired hosts.

There are also some traps that are used from switches to get quick updates when link status changes.

See documentation for details:

Cisco Application Policy Infrastructure Controller Enterprise Module Configuration Guide, Release 1.3.x - Device Config…

SNMP Trap Configuration

To ensure that Cisco APIC-EM captures data about the hosts connected to your network devices, you must set up SNMP traps or notifications. Enter the following SNMP commands to set up SNMP traps on the devices that connect to hosts within your network:

1. snmp-server enable traps snmp linkdown linkup
2. snmp-server host IP address version 2c public

Note	For Cisco Nexus devices, enter the following SNMP commands instead of the commands listed above: snmp-server enable traps snmp linkdown linkup snmp-server host IP address use-vrf default

After configuring SNMP traps on the network devices, the following data is captured and made available in the controller's GUI:

• Host data including the MAC address, IP address, and type
• Device interface status

[badgujarsoyab1]

Hello Sir,

Device discovery is finding many hosts, however they are NOT showing up in the host inventory for wired host.

I am having question , How to enable IP tracking .

Pl guide.

[aradford]

You can do it from the controller,

admin->settings -> device controllability -> IPDT Autoconfig

or from the CLI

IP Device Tracking (IPDT) Overview - Cisco

[aradford]

Not by default anymore.

In 1.3 there is a beta feature to do this.

[yawming]

Discovery discover network devices.

[ngoldwat]

Thanks for the visual definitions

[aradford]

IP Device Tracking is required for host discovery.