[CentOS-virt] [Advice] CentOS6 + KVM + bonding + bridging

[Philip Durbin]

On 09/06/2012 12:19 PM, SilverTip257 wrote:
> My question to the members of this list is what bonding mode(s) are
> you using for a high availability setup?
> I welcome any advice/tips/gotchas on bridging to a bonded interface.

I'm not sure I'd call this high availability... but here's an example of 
bonding two ethernet ports (eth0 and eth1) together into a bond (mode 4) 
and then setting up a bridge for a VLAN (id 375) that some VMs can run on:

[root at kvm01a network-scripts]# grep -iv hwadd ifcfg-eth0
DEVICE=eth0
SLAVE=yes
MASTER=bond0
[root at kvm01a network-scripts]# grep -iv hwadd ifcfg-eth1
DEVICE=eth1
SLAVE=yes
MASTER=bond0
[root at kvm01a network-scripts]# cat ifcfg-bond0 | sed 's/[1-9]/x/g'
DEVICE=bond0
ONBOOT=yes
BOOTPROTO=static
IPADDR=x0.xxx.xx.xx
NETMASK=xxx.xxx.xxx.0
DNSx=xx0.xxx.xxx.xxx
DNSx=x0.xxx.xx.xx
DNSx=x0.xxx.xx.x0
[root at kvm01a network-scripts]# cat ifcfg-br375
DEVICE=br375
BOOTPROTO=none
TYPE=Bridge
ONBOOT=yes
[root at kvm01a network-scripts]# cat ifcfg-bond0.375
DEVICE=bond0.375
BOOTPROTO=none
ONBOOT=yes
VLAN=yes
BRIDGE=br375
[root at kvm01a network-scripts]# cat /etc/modprobe.d/local.conf
alias bond0 bonding
options bonding mode=4 miimon=100
[root at kvm01a network-scripts]# grep Mode /proc/net/bonding/bond0
Bonding Mode: IEEE 802.3ad Dynamic link aggregation
[root at kvm01a network-scripts]# egrep '^V|375' /proc/net/vlan/config
VLAN Dev name	 | VLAN ID
bond0.375      | 375  | bond0

Repeat ad nauseam for the other VLANs you want to put VMs on (assuming 
your switch is trunking them to your hypervisor).

See also http://backdrift.org/howtonetworkbonding via 
http://irclog.perlgeek.de/crimsonfu/2012-08-15#i_5900501

Phil