Red Hat Bugzilla – Bug 672657
secondary interface eth1 using (interface type=ethernet) not working on guests
Last modified: 2011-02-12 09:32:45 EST
Description of problem:
I used two interfaces for child vm eth0 and eth1 using interface type = ethernet, eth0 is working but eth1 is not working.
Version-Release number of selected component (if applicable): 0.8.2-1
Steps to Reproduce:
1. Start child VM for 2 interfaces supporting using interface type = ethernet
-net nic,macaddr=xxx:fe,vlan=0,name=nic0 -net
2. Above script create tap interface and add desire ip route automatically, i mention the detail of script in Additional info section.
3. On child up the eth1 and ping from kvm host , its not pinging/responding.
when try to ping eth1 from kvm host, its gives destination unreachable, as eth0 is pinging . tcpdump on eth1 guest and arp results on kvm host shows below.
tcpdump on eth1
17:05:55.213100 ARP, Request who-has 126.96.36.199 tell x.x.x.x, length 46
17:05:56.213493 ARP, Request who-has 188.8.131.52 tell x.x.x.xlength 46
Arp -e results on kvm host
Address HWtype HWaddress Flags Mask Iface
x.x.x.x ether 52:54:00:56:40:56 C tap1 --> ok for eth0
x.x.x.x (incomplete) tap2 --> problem for eth1
eth1 should be ping and accessible from kvm host and from outer world.
Child VM OS = Fedora-13 also
Above Network script use below
IP= x.x.x.x # (ip of eth1)
SIP=x.x.x.x # (ip of kvm host)
tap=`ifconfig |grep $TAP`
if [ "$tap" == '' ] ;then
tap=`tunctl -b -u root -t $TAP`
ifconfig $TAP $SIP netmask 255.255.255.255 up
echo 1 > /proc/sys/net/ipv4/conf/$TAP/proxy_arp
route=`ip route show |grep $IP`
if [ "$route" == '' ] ;then
ip route add $IP/32 dev $TAP
Same above all is working for eth0 , but eth1 is not working/responding. I sure if same is working for eth0 then it must be working for eth1, but it cant work, after FC11. Kindly suggest please, we are very badly suffer this behaviour.
Any suggestions please ? , we are badly suffer from this problem.
I think i have now reach near to the problem, eth1 is basically receiving packets but not transmit data, i think reason is eth1 shares both an interrupt and memory access address with usb device,
0: 219 IO-APIC-edge timer
1: 6 IO-APIC-edge i8042
4: 88 IO-APIC-edge serial
8: 1 IO-APIC-edge rtc0
9: 0 IO-APIC-fasteoi acpi
10: 32103630 IO-APIC-fasteoi eth0
11: 330595 IO-APIC-fasteoi uhci_hcd:usb1, eth1
As see in 11: , how can i fix or change interrupts for eth1 on child guest ? kindly suggest please. Can i try to disable usb device ?