I was testing VPP with 5 VLAN networks interfaces attached to a single VM. When the VM boots up, one of the network interfaces is not able to get the DHCP leased IP.

I debugged further by manually adding a fixed IP address on the not working interface and tried to ping the DHCP server.

From the DHCP server, I am able to see it response the ARP request. But on the VM host side, the vpp packet trace is not correct:

Packet 13

00:37:57:786589: dpdk-input
BondEthernet0 rx queue 0
buffer 0x89e2: current data 0, length 46, free-list 0, totlen-nifb 0, trace 0xc
PKT MBUF: port 1, nb_segs 1, pkt_len 46
buf_len 2176, data_len 46, ol_flags 0x0, data_off 128, phys_addr 0x3d423780
packet_type 0x0
ARP: fa:16:3e:de:3c:98 -> fa:16:3e:d3:03:a6 802.1q vlan 2005
reply, type ethernet/IP4, address size 6/4
fa:16:3e:de:3c:98/10.0.4.2 -> fa:16:3e:d3:03:a6/10.0.4.6
00:37:57:786605: ethernet-input
ARP: fa:16:3e:de:3c:98 -> fa:16:3e:d3:03:a6 802.1q vlan 2005
00:37:57:786610: l2-input
l2-input: sw_if_index 23 dst fa:16:3e:d3:03:a6 src fa:16:3e:de:3c:98
00:37:57:786610: l2-input-vtr
l2-input-vtr: sw_if_index 23 dst fa:16:3e:d3:03:a6 src fa:16:3e:de:3c:98 data 08 06 00 01 08 00 06 04 00 02 fa 16
00:37:57:786612: l2-learn
l2-learn: sw_if_index 23 dst fa:16:3e:d3:03:a6 src fa:16:3e:de:3c:98 bd_index 5
00:37:57:786612: l2-fwd
l2-fwd: sw_if_index 23 dst fa:16:3e:d3:03:a6 src fa:16:3e:de:3c:98 bd_index 5
00:37:57:786614: l2-output
l2-output: sw_if_index 16 dst fa:16:3e:d3:03:a6 src fa:16:3e:de:3c:98
00:37:57:786614: l2-output-classify
l2-classify: sw_if_index 16, table -1, offset 0, next 21
00:37:57:786614: VirtualEthernet0/0/7-output
VirtualEthernet0/0/14
ARP: fa:16:3e:de:3c:98 -> fa:16:3e:d3:03:a6
reply, type ethernet/IP4, address size 6/4
fa:16:3e:de:3c:98/10.0.4.2 -> fa:16:3e:d3:03:a6/10.0.4.6
00:37:57:786618: VirtualEthernet0/0/7-tx
VirtualEthernet0/0/7 queue 0
virtio flags:
SINGLE_DESC Single descriptor packet
virtio_net_hdr first_desc_len 4096
flags 0x00 gso_type 0
num_buff 1

Somehow the packet belongs to VirtualEthernet0/0/14 goes to VirtualEthernet0/0/7 instead.