When trying to configure dhcp in ASR 9k, got into some problems.
First, ASR 9k does not have dhcp server, at least till version 4.3.2. You will always need a external dhcp server.
So, when configuring dhcp relay to my corporate dhcp, here's what I found:
Does not work:
interface bvi2
ipv4 helper-address vrf CORP 10.1.100.10
ipv4 helper-address vrf CORP 10.2.100.10
Works:
dhcp ipv4
profile CORP_DHCP relay
helper-address vrf CORP 10.1.100.10
helper-address vrf CORP 10.2.100.10
!
dhcp ipv4 interface bvi2 relay profile CORP_DHCP
Hope it helps! Regards