How to identify DomU's ip without login to it
1. Find domU's mac:
localhost:~# xm network-list 5 | grep -v MAC | awk '{print $3}'
00:16:3e:03:47:36
2. Find domU's bridge
localhost:~# brctl show
bridge name bridge id STP enabled interfaces
eth0 8000.1c6f650addfe no vif5.0
peth0
virbr0 8000.000000000000 yes
So the bridge of domU (id: 5) is eth0
3. Use tcpdump to identify domU's ip
localhost:~# tcpdump -n -i eth0 ether src 00:16:3e:03:47:36
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
16:47:11.320253 IP 192.168.25.22.filenet-rpc > 192.168.100.10.domain: 39150+ A? www.baidu.com. (31)
16:47:11.320995 IP 192.168.25.22 > 119.75.218.77: ICMP echo request, id 35854, seq 1, length 64
16:47:11.349207 IP 192.168.25.22.filenet-rpc > 192.168.100.10.domain: 15635+ PTR? 77.218.75.119.in-addr.arpa. (44)
So the ip of domU (id: 5) is 192.168.25.22
Note: This method requires that the vm must be sending some packets to internet.