[root@controller ~]# cat /etc/hosts
# controller
10.0.0.11       controller
# compute1
10.0.0.31       compute1
# block1
10.0.0.41       block1
# object1
10.0.0.51       object1
# object2
10.0.0.52       object2

127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
::1         localhost localhost.localdomain localhost6 localhost6.localdomain6