This looks like a duplicate of LP: #1271144
We can see from the landscape-sysinfo output
" Memory usage: 5% IP address for eth0: 10.0.100.114 Swap usage: 0% IP address for lxcbr0: 10.0.3.1 "
That you have eth0, lxcbr0 and not br0 itself. This leads to lxc-start not working, which then gives that wonderful error message :)
This looks like a duplicate of LP: #1271144
We can see from the landscape-sysinfo output
" Memory usage: 5% IP address for eth0: 10.0.100.114
Swap usage: 0% IP address for lxcbr0: 10.0.3.1
"
That you have eth0, lxcbr0 and not br0 itself. This leads to lxc-start not working, which then gives that wonderful error message :)