external network doesn't work directly connecting

edit

I got running Hyper-V compute node and a Controller/Network node on a separate linux server. This configurations working well on KVM compute nodes (which I remove all networks, disable kvm compute nodes prior to testing this)

As per testing, i used to upload a Centos 6.5 image. I made 2 instances, 1 VM directly connected to the external network (aka public network) and 1 VM connected to the private network which routed to the external network.

But my questions now why directly connecting to the external network doesn't work or not able to ping the NIC connected to the external router (10.20.30.254)?

ip netns 
qrouter-94683fda-8425-44e4-a3b9-011146d3db3c
qdhcp-40c419d7-9b49-4566-a5b6-c01dc270dbdf
qdhcp-8971a629-8326-466a-979a-c39401245043

IPs are the following (remove lo):

ip netns exec qdhcp-40c419d7-9b49-4566-a5b6-c01dc270dbdf ifconfig
tap84ddb98a-6f: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1450
        inet 10.0.1.2  netmask 255.255.255.0  broadcast 10.0.1.255
        inet6 fe80::f816:3eff:fe6e:60a1  prefixlen 64  scopeid 0x20<link>
        ether fa:16:3e:6e:60:a1  txqueuelen 0  (Ethernet)
        RX packets 585  bytes 29880 (29.1 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 32  bytes 4761 (4.6 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

and this is directly connected external network

ip netns exec qdhcp-8971a629-8326-466a-979a-c39401245043 ifconfig
tap344a41fd-c9: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1450
        inet 10.20.30.20  netmask 255.255.255.0  broadcast 10.20.30.255
        inet6 fe80::f816:3eff:fef4:7072  prefixlen 64  scopeid 0x20<link>
        ether fa:16:3e:f4:70:72  txqueuelen 0  (Ethernet)
        RX packets 1342  bytes 67134 (65.5 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 138  bytes 12426 (12.1 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

Gateways:

ip netns exec qdhcp-8971a629-8326-466a-979a-c39401245043 route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.20.30.254    0.0.0.0         UG    0      0        0 tap344a41fd-c9
10.20.30.0      0.0.0.0         255.255.255.0   U     0      0        0 tap344a41fd-c9

ip netns exec qdhcp-40c419d7-9b49-4566-a5b6-c01dc270dbdf route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.0.1.1        0.0.0.0         UG    0      0        0 tap84ddb98a-6f
10.0.1.0        0.0.0.0         255.255.255.0   U     0      0        0 tap84ddb98a-6f

Pinging the main gateway (10.20.30.254).

ip netns exec qdhcp-8971a629-8326-466a-979a-c39401245043 ping 10.20.30.254
PING 10.20.30.254 (10.20.30.254) 56(84) bytes of data.
From 10.20.30.20 icmp_seq=1 Destination Host Unreachable
From 10.20.30.20 icmp_seq=2 Destination Host Unreachable

ip netns exec qdhcp-40c419d7-9b49-4566-a5b6-c01dc270dbdf ping 10.20.30.254
PING 10.20.30.254 (10.20.30.254) 56(84) bytes of data.
64 bytes from 10.20.30.254: icmp_seq=1 ttl=127 time=5.77 ms
^C
--- 10.20.30.254 ping statistics ---
1 ...