Destination net unreachable?

Question

Hi all, 
 While trying to set up Sophos XG on a Hyper-V VM with two virtual network adapters, I came across this problem: 
 XG has no internet access at all because apparently it cannot access any internet IPs. I've verified this by attempting to ping 8.8.8.8 in the console and getting a "Reply from 192.168.1.1: Destination net unreachable" error. I have a Technicolor TG587N modem that I've assigned the Public IP of to the Sophos XG's virtual NIC. NO other devices are connected to the modem and the NICs are set for the exclusive use of the Guest OS only. 
 Here are my settings for the LAN: 
 IP address: 192.168.1.1 
 Netmask: 255.255.255.0 
 And for the WAN (DHCP): 
 IP address: 120.146.239.204 
 Netmask: 255.0.0.0 
 Gateway: 172.18.113.15 
 Output of netstat -rn: 
 Kernel IP routing table 
 Destination Gateway Genmask Flags MSS Window irtt Iface 
 10.255.0.0 0.0.0.0 255.255.255.0 U 0 0 0 GuestAP 
 120.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 Port2 
 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 Port1 
 Output of ifconfig: 
 GuestAP Link encap:Ethernet HWaddr F2:66:D6:F4:D7:6D 
 inet addr:10.255.0.1 Bcast:10.255.0.255 Mask:255.255.255.0 
 UP BROADCAST MULTICAST MTU:1500 Metric:1 
 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 
 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 
 collisions:0 txqueuelen:0 
 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) 
 Port1 Link encap:Ethernet HWaddr 00:15:5D:01:35:00 
 inet addr:192.168.1.1 Bcast:192.168.1.255 Mask:255.255.255.0 
 inet6 addr: fe80::215:5dff:fe01:3500/64 Scope:Link 
 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 
 RX packets:3004 errors:0 dropped:0 overruns:0 frame:0 
 TX packets:352 errors:0 dropped:0 overruns:0 carrier:0 
 collisions:0 txqueuelen:1000 
 RX bytes:241581 (235.9 KiB) TX bytes:37728 (36.8 KiB) 
 Port2 Link encap:Ethernet HWaddr 00:15:5D:01:35:01 
 inet addr:120.146.239.204 Bcast:120.255.255.255 Mask:255.0.0.0 
 inet6 addr: fe80::215:5dff:fe01:3501/64 Scope:Link 
 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 
 RX packets:1669 errors:0 dropped:0 overruns:0 frame:0 
 TX packets:139 errors:0 dropped:0 overruns:0 carrier:0 
 collisions:0 txqueuelen:1000 
 RX bytes:473884 (462.7 KiB) TX bytes:26602 (25.9 KiB) 
 imq00-00 Link encap:UNSPEC HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00 
 
 UP RUNNING NOARP MTU:16000 Metric:1 
 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 
 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 
 collisions:0 txqueuelen:11000 
 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) 
 ipsec0 Link encap:Ethernet HWaddr D6:9D:80:80:BD:62 
 inet addr:169.254.234.5 Bcast:0.0.0.0 Mask:255.255.255.255 
 inet6 addr: fe80:d49d:80ff:fe80:bd72/64 Scope:Link 
 UP BROADCAST RUNNING NOARP MULTICAST MTU:16260 Metric:1 
 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 
 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 
 collisions:0 txqueuelen:0 
 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) 
 lo Link encap:Local Loopback 
 inet addr:127.0.0.1 Mask:255.0.0.0 
 inet6 addr: fe80::215:5dff:fe01:3500/64 Scope:Link 
 UP LOOPBACK RUNNING MTU:65536 Metric:1 
 RX packets:29618 errors:0 dropped:0 overruns:0 frame:0 
 TX packets:29618 errors:0 dropped:0 overruns:0 carrier:0 
 collisions:0 txqueuelen:0 
 RX bytes:6642108 (6.3 MiB) TX bytes:6642108 (6.3 MiB) 
 Please help! I've been at this for around 4 hours and my family is pestering me to get the internet fixed :/

Aditya Patel · Answer

HI Joseph, 
 I would like to help you with your issue . 
 First Step is to provide a Rough Diagram with the Host addresses of both XG and your Router . with LAN and WAN addresses. 
 Secondly since you are using XG in Gateway mode , are you using your WAN router in Gateway or used in Bridge Connection . 
 Finally , Check on the Packet capture while you ping 8.8.8.8 on console , you may check if the packet is indeed traversing through XG or not . Command would be 
 console> tcpdump 'host 8.8.8.8 and icmp 
 Let me know your findings and post them . 
 Thanks and Regards 
 Aditya Patel