Now that the three servers should be communicating properly, let's take a look. On each server, start a tcpdump:
In this case, look for all traffic on port 8000 (sending or receiving) as that is Kazoo's default API port.
# Laptop
11:06:24.242471 IP (tos 0x0, ttl 64, id 21252, offset 0, flags [DF], proto TCP (6), length 60)
laptop.49560 > VM.8000: Flags [S], cksum 0xfcf3 (incorrect -> 0x04e3), seq 1995735410, win 29200, options [mss 1460,sackOK,TS val 3284285253 ecr 0,nop,wscale 7], length 0
11:06:24.243341 IP (tos 0x0, ttl 63, id 0, offset 0, flags [DF], proto TCP (6), length 60)
VM.8000 > laptop.49560: Flags [S.], cksum 0x73bf (correct), seq 2588808479, ack 1995735411, win 28960, options [mss 1460,sackOK,TS val 83877269 ecr 3284285253,nop,wscale 7], length 0
11:06:24.243385 IP (tos 0x0, ttl 64, id 21253, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > VM.8000: Flags [.], cksum 0xfceb (incorrect -> 0x12c6), seq 1, ack 1, win 229, options [nop,nop,TS val 3284285254 ecr 83877269], length 0
11:06:24.243452 IP (tos 0x0, ttl 64, id 21254, offset 0, flags [DF], proto TCP (6), length 135)
laptop.49560 > VM.8000: Flags [P.], cksum 0xfd3e (incorrect -> 0xe0bf), seq 1:84, ack 1, win 229, options [nop,nop,TS val 3284285254 ecr 83877269], length 83
11:06:24.244169 IP (tos 0x0, ttl 63, id 51382, offset 0, flags [DF], proto TCP (6), length 52)
VM.8000 > laptop.49560: Flags [.], cksum 0x1274 (correct), seq 1, ack 84, win 227, options [nop,nop,TS val 83877270 ecr 3284285254], length 0
11:06:24.445887 IP (tos 0x0, ttl 63, id 51383, offset 0, flags [DF], proto TCP (6), length 2798)
VM.8000 > laptop.49560: Flags [P.], cksum 0x07a6 (incorrect -> 0x7cb2), seq 1:2747, ack 84, win 227, options [nop,nop,TS val 83877472 ecr 3284285254], length 2746
11:06:24.445911 IP (tos 0x0, ttl 64, id 21255, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > VM.8000: Flags [.], cksum 0xfceb (incorrect -> 0x05f9), seq 84, ack 2747, win 272, options [nop,nop,TS val 3284285456 ecr 83877472], length 0
11:06:24.446377 IP (tos 0x0, ttl 64, id 21256, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > VM.8000: Flags [F.], cksum 0xfceb (incorrect -> 0x05f7), seq 84, ack 2747, win 272, options [nop,nop,TS val 3284285457 ecr 83877472], length 0
11:06:24.447064 IP (tos 0x0, ttl 63, id 51385, offset 0, flags [DF], proto TCP (6), length 52)
VM.8000 > laptop.49560: Flags [F.], cksum 0x0622 (correct), seq 2747, ack 85, win 227, options [nop,nop,TS val 83877473 ecr 3284285457], length 0
11:06:24.447090 IP (tos 0x0, ttl 64, id 21257, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > VM.8000: Flags [.], cksum 0xfceb (incorrect -> 0x05f4), seq 85, ack 2748, win 272, options [nop,nop,TS val 3284285458 ecr 83877473], length 0
# Dev machine (host)
laptop.49560 > 192.168.122.21.8000: Flags [S], cksum 0x04e3 (correct), seq 1995735410, win 29200, options [mss 1460,sackOK,TS val 3284285253 ecr 0,nop,wscale 7], length 0
18:06:24.240212 IP (tos 0x0, ttl 63, id 0, offset 0, flags [DF], proto TCP (6), length 60)
192.168.122.21.8000 > laptop.49560: Flags [S.], cksum 0xfcf3 (incorrect -> 0x73bf), seq 2588808479, ack 1995735411, win 28960, options [mss 1460,sackOK,TS val 83877269 ecr 3284285253,nop,wscale 7], length 0
18:06:24.240672 IP (tos 0x0, ttl 64, id 21253, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > 192.168.122.21.8000: Flags [.], cksum 0x12c6 (correct), seq 1, ack 1, win 229, options [nop,nop,TS val 3284285254 ecr 83877269], length 0
18:06:24.240702 IP (tos 0x0, ttl 64, id 21254, offset 0, flags [DF], proto TCP (6), length 135)
laptop.49560 > 192.168.122.21.8000: Flags [P.], cksum 0xe0bf (correct), seq 1:84, ack 1, win 229, options [nop,nop,TS val 3284285254 ecr 83877269], length 83
18:06:24.241046 IP (tos 0x0, ttl 63, id 51382, offset 0, flags [DF], proto TCP (6), length 52)
192.168.122.21.8000 > laptop.49560: Flags [.], cksum 0xfceb (incorrect -> 0x1274), seq 1, ack 84, win 227, options [nop,nop,TS val 83877270 ecr 3284285254], length 0
18:06:24.442439 IP (tos 0x0, ttl 63, id 51383, offset 0, flags [DF], proto TCP (6), length 2798)
192.168.122.21.8000 > laptop.49560: Flags [P.], cksum 0x07a6 (incorrect -> 0x7cb2), seq 1:2747, ack 84, win 227, options [nop,nop,TS val 83877472 ecr 3284285254], length 2746
18:06:24.443185 IP (tos 0x0, ttl 64, id 21255, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > 192.168.122.21.8000: Flags [.], cksum 0x05f9 (correct), seq 84, ack 2747, win 272, options [nop,nop,TS val 3284285456 ecr 83877472], length 0
18:06:24.443660 IP (tos 0x0, ttl 64, id 21256, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > 192.168.122.21.8000: Flags [F.], cksum 0x05f7 (correct), seq 84, ack 2747, win 272, options [nop,nop,TS val 3284285457 ecr 83877472], length 0
18:06:24.443935 IP (tos 0x0, ttl 63, id 51385, offset 0, flags [DF], proto TCP (6), length 52)
192.168.122.21.8000 > laptop.49560: Flags [F.], cksum 0xfceb (incorrect -> 0x0622), seq 2747, ack 85, win 227, options [nop,nop,TS val 83877473 ecr 3284285457], length 0
18:06:24.444356 IP (tos 0x0, ttl 64, id 21257, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > 192.168.122.21.8000: Flags [.], cksum 0x05f4 (correct), seq 85, ack 2748, win 272, options [nop,nop,TS val 3284285458 ecr 83877473], length 0
# VM
18:06:24.243655 IP (tos 0x0, ttl 63, id 21252, offset 0, flags [DF], proto TCP (6), length 60)
laptop.49560 > vm.8000: Flags [S], cksum 0x04e3 (correct), seq 1995735410, win 29200, options [mss 1460,sackOK,TS val 3284285253 ecr 0,nop,wscale 7], length 0
18:06:24.243713 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto TCP (6), length 60)
vm.8000 > laptop.49560: Flags [S.], cksum 0xfcf3 (incorrect -> 0x73bf), seq 2588808479, ack 1995735411, win 28960, options [mss 1460,sackOK,TS val 83877269 ecr 3284285253,nop,wscale 7], length 0
18:06:24.244510 IP (tos 0x0, ttl 63, id 21253, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > vm.8000: Flags [.], cksum 0x12c6 (correct), seq 1, ack 1, win 229, options [nop,nop,TS val 3284285254 ecr 83877269], length 0
18:06:24.244543 IP (tos 0x0, ttl 63, id 21254, offset 0, flags [DF], proto TCP (6), length 135)
laptop.49560 > vm.8000: Flags [P.], cksum 0xe0bf (correct), seq 1:84, ack 1, win 229, options [nop,nop,TS val 3284285254 ecr 83877269], length 83
18:06:24.244555 IP (tos 0x0, ttl 64, id 51382, offset 0, flags [DF], proto TCP (6), length 52)
vm.8000 > laptop.49560: Flags [.], cksum 0xfceb (incorrect -> 0x1274), seq 1, ack 84, win 227, options [nop,nop,TS val 83877270 ecr 3284285254], length 0
18:06:24.445989 IP (tos 0x0, ttl 64, id 51383, offset 0, flags [DF], proto TCP (6), length 2798)
vm.8000 > laptop.49560: Flags [P.], cksum 0x07a6 (incorrect -> 0x7cb2), seq 1:2747, ack 84, win 227, options [nop,nop,TS val 83877472 ecr 3284285254], length 2746
18:06:24.446930 IP (tos 0x0, ttl 63, id 21255, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > vm.8000: Flags [.], cksum 0x05f9 (correct), seq 84, ack 2747, win 272, options [nop,nop,TS val 3284285456 ecr 83877472], length 0
18:06:24.447336 IP (tos 0x0, ttl 63, id 21256, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > vm.8000: Flags [F.], cksum 0x05f7 (correct), seq 84, ack 2747, win 272, options [nop,nop,TS val 3284285457 ecr 83877472], length 0
18:06:24.447502 IP (tos 0x0, ttl 64, id 51385, offset 0, flags [DF], proto TCP (6), length 52)
vm.8000 > laptop.49560: Flags [F.], cksum 0xfceb (incorrect -> 0x0622), seq 2747, ack 85, win 227, options [nop,nop,TS val 83877473 ecr 3284285457], length 0
18:06:24.448032 IP (tos 0x0, ttl 63, id 21257, offset 0, flags [DF], proto TCP (6), length 52)
laptop.49560 > vm.8000: Flags [.], cksum 0x05f4 (correct), seq 85, ack 2748, win 272, options [nop,nop,TS val 3284285458 ecr 83877473], length 0