Device does not activate IP address received via DHCP

Discovered in TCP/IP interface test (Test 12/13) during CT22: DUT is not reachable under its IP address that has been assigned via DHCP. After Link Down / Link Up, the device is reachable again.

Extract from Wireshark trace:

The issue is also reproducible with Hilscher EtherNet/IP Tool:

• Have a DHCP server running
• Use connected explicit messaging with large forward open
• In TCP/IP Interface object set Configuration Method to Static IP
• Set a static IP address differing from the one assigned by DHCP
• In TCP/IP Interface object set Configuration Method to DHCP
• DHCP sequence starts as shown in the Wireshark trace above
• DUT is not reachable under the requested IP address
• No ACD Probing ARP frames
• As the issue is not easy to reproduce, there might be multiple runs of that sequence needed to reproduce it.