Hi,
I have a Centos7 host with libvirt, attempting to boot a Centos7 guest.
I am attempting to do the install over ipv6 (because why not).
I have the following network configuration.
Cisco 3550 gi0/1 <-> eno1 (Centos7) host.
gi0/1 is configured as:
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 1-17
switchport mode trunk
Mainly in question is vlan11 as this is the network I am trying to work
with.
The switch have vlan11 configured with STP:
# sh spa v 11
VLAN0011
Spanning tree enabled protocol rstp
Root ID Priority 12299
Address 000c.30d1.9700
This bridge is the root
Hello Time 2 sec Max Age 10 sec Forward Delay 5 sec
Bridge ID Priority 12299 (priority 12288 sys-id-ext 11)
Address 000c.30d1.9700
Hello Time 2 sec Max Age 10 sec Forward Delay 5 sec
Aging Time 300
Interface Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- --------
--------------------------------
Gi0/1 Desg FWD 4 128.25 P2p
Gi0/2 Desg FWD 4 128.26 P2p
Notice that the switch is the root of the STP.
The Centos7 host network is configured as:
DEVICE="eno1.11"
VLAN="yes"
BOOTPROTO="none"
IPV6INIT="no"
IPV6_AUTOCONF="no"
NM_CONTROLLED="no"
ONBOOT="yes"
TYPE="Ethernet"
BRIDGE=br11
With the corresponding bridge as:
DEVICE=br11
ONBOOT=yes
BOOTPROTO=none
TYPE=Bridge
IPV4_FAILURE_FATAL=no
IPV6_FAILURE_FATAL=no
NM_CONTROLLED=no
IPV6INIT=yes
IPV6_AUTOCONF=yes
IPV6_ROUTER=no
STP=off
The output of ip a for these interfaces is as such:
5: eno1.11 at eno1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc
noqueue master br11 state UP
link/ether c0:3f:d5:61:c8:ec brd ff:ff:ff:ff:ff:ff
inet6 fe80::c23f:d5ff:fe61:c8ec/64 scope link
valid_lft forever preferred_lft forever
6: br11: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state
UP
link/ether c0:3f:d5:61:c8:ec brd ff:ff:ff:ff:ff:ff
inet6 fe80::c23f:d5ff:fe61:c8ec/64 scope link
valid_lft forever preferred_lft forever
brctl show br11
bridge name bridge id STP enabled interfaces
br11 8000.c03fd561c8ec yes eno1.11
vnet1
vnet1 being the interface of the connected vm.
When the VM is booted, the following error is received.
[ OK ] Reached target Paths.
[ OK ] Reached target Basic System.
[ 33.874572] IPv6: eth0: IPv6 duplicate address
2001:db8:0:11:5054:ff:fedd:a617 detected!
Any address assigned to the interface immediately triggers a dadfailed
warning such as:
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast
state UP qlen 1000
link/ether 52:54:00:dd:a6:17 brd ff:ff:ff:ff:ff:ff
inet6 2001:db8:0:11::200/64 scope global tentative dadfailed
valid_lft forever preferred_lft forever
inet6 fe80::5054:ff:fedd:a617/64 scope link
valid_lft forever preferred_lft forever
Assigning an ipv4 address, traffic is correctly able to flow over the
bridge via the switch to other hosts.
I am suspicious that the issue lays somewhere in ND being reflected from
the cisco in some capacity perhaps?
A fedora 20 system connected to gi0/2, with identical network
configuration and switch does not suffer this issue when booting guests.
This has left me quite stumped as to what I am doing wrong on the
Centos7 host, or if there is another issue.
And help would be greatly appreciated in helping solve this issue.
