IP device tracking ON or OFF

[Sebastian Helmer]

HI there,

I think IPDT IP device tracking is a cool feature and for APIC EM I'm checking out right now, it seems to be necessary.
But apart from APIC EM why should I NOT turn on IPDT? Are there reasons not to do that? Performance, BUGs, Problems??

I'd like to enable that on all my 2960 access (around 70) and 3750 (around 8 they were all stacked versions with 2-6 members) distribution switches. Example for one of the biggest LAN we have.

would be nice to get any experience or meaning.

thanks, Sebastian

[pwwiddicombe]

There are some conditions where IPDT being enabled may interfere with DHCP or duplicate address detection.  For devices not online, the switch will ARP for these; and the end device putting through a DHCP request will see that another device is already ARP'ing from another source address.

See http://www.cisco.com/c/en/us/support/docs/ip/address-resolution-protocol-arp/118630-technote-ipdt-00.html#anc3 ; "Known issue".

[Justin bollinger]

Also beware that on manufacturing/SCADA networks or any networks that include PLCs the ip device tracking feature can cause the PLC to identify that there is a duplicate IP address and cause the PLC to go offline.