C:\Windows\system32>nmap --iflist Starting Nmap 6.01 ( http://nmap.org ) at 2012-08-31 06:51 Central Daylight Time ************************INTERFACES************************ DEV (SHORT) IP/MASK TYPE UP MTU MAC eth0 (eth0) fe80::797f:b9b6:3ee0:27b8/64 ethernet down 1500 5C:AC:4C:E9:2D:46 eth0 (eth0) 169.254.39.184/4 ethernet down 1500 5C:AC:4C:E9:2D:46 eth1 (eth1) fe80::5c02:7e48:8fbe:c7c9/64 ethernet down 1500 00:FF:3F:7C:7C:2B eth1 (eth1) 169.254.199.201/4 ethernet down 1500 00:FF:3F:7C:7C:2B eth2 (eth2) fe80::74e4:1ab7:1b7d:a0d0/64 ethernet up 1500 14:FE:B5:BA:8A:C3 eth2 (eth2) 10.0.0.0.253/24 ethernet up 1500 14:FE:B5:BA:8A:C3 eth3 (eth3) fe80::b03e:ddf5:bb5c:5f76/64 ethernet up 1500 00:50:56:C0:00:01 eth3 (eth3) 169.254.95.118/16 ethernet up 1500 00:50:56:C0:00:01 eth4 (eth4) fe80::b175:831d:e60:27b/64 ethernet up 1500 00:50:56:C0:00:08 eth4 (eth4) 192.168.153.1/24 ethernet up 1500 00:50:56:C0:00:08 lo0 (lo0) ::1/128 loopback up -1 lo0 (lo0) 127.0.0.1/8 loopback up -1 tun0 (tun0) fe80::100:7f:fffe/64 point2point down 1280 tun1 (tun1) (null)/0 point2point down 1280 tun2 (tun2) fe80::5efe:a9fe:5f76/128 point2point down 1280 tun3 (tun3) (null)/0 point2point down 1280 tun4 (tun4) fe80::5efe:c0a8:9901/128 point2point down 1280 tun5 (tun5) fe80::5efe:ac14:fd/128 point2point down 1280 DEV WINDEVICE eth0 \Device\NPF_{0024872A-5A41-42DF-B484-FB3D3ED3FCE9} eth0 \Device\NPF_{0024872A-5A41-42DF-B484-FB3D3ED3FCE9} eth1 \Device\NPF_{3F7C7C2B-9AF3-45BB-B96E-2F00143CC2F7} eth1 \Device\NPF_{3F7C7C2B-9AF3-45BB-B96E-2F00143CC2F7} eth2 \Device\NPF_{08116FE5-F0FF-498A-9BF1-515528C57C13} eth2 \Device\NPF_{08116FE5-F0FF-498A-9BF1-515528C57C13} eth3 \Device\NPF_{AA83C6CE-AB2E-4764-92D1-CDEAFBA7AD21} eth3 \Device\NPF_{AA83C6CE-AB2E-4764-92D1-CDEAFBA7AD21} eth4 \Device\NPF_{D0679889-E9D4-411D-BDC5-F4DDB758E151} eth4 \Device\NPF_{D0679889-E9D4-411D-BDC5-F4DDB758E151} lo0 <none> lo0 <none> tun0 <none> tun1 <none> tun2 <none> tun3 <none> tun4 <none> tun5 <none> **************************ROUTES************************** DST/MASK DEV GATEWAY 192.168.153.255/32 eth0 255.255.255.255/32 eth0 255.255.255.255/32 eth0 127.0.0.1/32 eth0 127.255.255.255/32 eth0 255.255.255.255/32 eth0 169.254.95.118/32 eth0 169.254.255.255/32 eth0 10.0.0.0.253/32 eth0 255.255.255.255/32 eth0 10.0.0.0.255/32 eth0 255.255.255.255/32 eth0 192.168.153.1/32 eth0 255.255.255.255/32 eth0 10.0.0.0.0/24 eth0 192.168.153.0/24 eth0 10.10.10.0/24 eth0 10.0.0.0.4 169.254.0.0/16 eth0 127.0.0.0/8 eth0 224.0.0.0/4 eth0 224.0.0.0/4 eth0 224.0.0.0/4 eth0 224.0.0.0/4 eth0 224.0.0.0/4 eth0 224.0.0.0/4 eth0 0.0.0.0/0 eth0 10.0.0.0.1 JMeterX - I worded that way in hopes of raising answer efficnecy, but that probably wasnt the smartest choice. IMHO the problem (could be a symptom) is that nmap retardedly chooses eth0 as the gateway interface for any and all networks. Here's the result: C:\Windows\system32>nmap 10.0.0.55 Starting Nmap 6.01 ( http://nmap.org ) at 2012-08-31 07:43 Central Daylight Time Note: Host seems down. If it is really up, but blocking our ping probes, try -Pn Nmap done: 1 IP address (0 hosts up) scanned in 0.95 seconds C:\Windows\system32>nmap -e eth2 10.0.0.55 Starting Nmap 6.01 ( http://nmap.org ) at 2012-08-31 07:44 Central Daylight Time Nmap scan report for esxy5.dionne.net (10.0.0.55) Host is up (0.00070s latency). Not shown: 991 filtered ports PORT STATE SERVICE 22/tcp open ssh 80/tcp open http 427/tcp open svrloc 443/tcp open https 902/tcp open iss-realsecure 5988/tcp closed wbem-http 5989/tcp open wbem-https 8000/tcp open http-alt 8100/tcp open xprint-server MAC Address: 00:1F:29:59:C7:03 (Hewlett-Packard Company) Nmap done: 1 IP address (1 host up) scanned in 5.29 seconds Just to be clear, this is what makes absolutly no sense to me whatsoever. For reference, I've included similar info from an Ubuntu (that works normally) vm on the affected host below. Jacked Windows 7 **************************ROUTES************************** DST/MASK DEV GATEWAY 192.168.153.255/32 eth0 255.255.255.255/32 eth0 255.255.255.255/32 eth0 127.0.0.1/32 eth0 127.255.255.255/32 eth0 255.255.255.255/32 eth0 169.254.95.118/32 eth0 169.254.255.255/32 eth0 10.0.0.0.253/32 eth0 255.255.255.255/32 eth0 10.0.0.0.255/32 eth0 255.255.255.255/32 eth0 192.168.153.1/32 eth0 255.255.255.255/32 eth0 10.0.0.0.0/24 eth0 192.168.153.0/24 eth0 10.10.10.0/24 eth0 10.0.0.0.4 169.254.0.0/16 eth0 127.0.0.0/8 eth0 224.0.0.0/4 eth0 224.0.0.0/4 eth0 224.0.0.0/4 eth0 224.0.0.0/4 eth0 224.0.0.0/4 eth0 224.0.0.0/4 eth0 0.0.0.0/0 eth0 10.0.0.0.1 Working Ubuntu VM root@ubuntu:~# nmap --iflist Starting Nmap 5.21 ( http://nmap.org ) at 2012-08-31 07:44 PDT ************************INTERFACES************************ DEV (SHORT) IP/MASK TYPE UP MAC lo (lo) 127.0.0.1/8 loopback up eth0 (eth0) 172.20.0.89/24 ethernet up 00:0C:29:0A:C9:35 eth1 (eth1) 192.168.225.128/24 ethernet up 00:0C:29:0A:C9:3F eth2 (eth2) 192.168.150.128/24 ethernet up 00:0C:29:0A:C9:49 **************************ROUTES************************** DST/MASK DEV GATEWAY 192.168.225.0/0 eth1 192.168.150.0/0 eth2 172.20.0.0/0 eth0 169.254.0.0/0 eth0 0.0.0.0/0 eth0 172.20.0.1 root@ubuntu:~# nmap esxy2 Starting Nmap 5.21 ( http://nmap.org ) at 2012-08-31 07:44 PDT Nmap scan report for esxy2 (172.20.0.52) Host is up (0.00036s latency). rDNS record for 172.20.0.52: esxy2.dionne.net Not shown: 994 filtered ports PORT STATE SERVICE 80/tcp open http 427/tcp closed svrloc 443/tcp open https 902/tcp closed iss-realsecure 8000/tcp open http-alt 8100/tcp open unknown MAC Address: 00:04:23:B1:FA:6A (Intel) Nmap done: 1 IP address (1 host up) scanned in 4.76 seconds