Found that there is a resync button in Device inventory. This function send signal to switch to get config file from PnP. Was triying to change config that is currently connected to switch in PnP and pushed Resync button was able to see log in switch "Mar 2 06:32:48: %SYS-5-CONFIG_I: Configured from console by apic on vty0", but it didn't take updated configuration from PnP. Using 1.4 version.
The re-sync option works the other way. It re-syncs the controller to the configuration and other state on the device.
PnP is a day0 operation. You only push the configuration once.
After that the device is added to the inventory and the controller keeps track of the device state.
This is unfortunately not the intention of resync. It's actually to manually sync devices in the inventory, e.g. if you run some tests and want immediate status reflection in APIC-EM instead of waiting the default poll time.
Have a look here for your reference (page 2): http://www.cisco.com/c/en/us/td/docs/cloud-systems-management/application-policy-infrastructure-controller-enterprise-module/1-4-x/network_visibility/release-notes/b_Cisco_Network_Visibility_Release_Notes_1_4_0_x.pdf
where can you change configuration on switches or reprovision it from APIC-EM ..
lots of plans to improve APIC-EM. In 1.4 we added CommandRunner that allows you to run exec commands on devices.
I would encourage you to use the "I wish this page would...." button on bottom right to make a wish to Product Management.