Eucalyptus apparently already has some crude support for this in net/vnetwork.c
So you *can* specify CIDR-style notation, like 192.168.0.128/25.
However if you specify a CIDR-style network that's not aligned to the first address, then it leads to a somewhat incorrect result:
so this leads to a correct result:
192.168.0.128/25 = 192.168.0.128 - 192.168.0.255 -> eucalyptus assigns 192.168.0.129 - 192.168.0.254
192.168.0.228/30 = 192.168.0.228 - 192.168.0.231 -> eucalyptus assigns 192.168.0.229 - 192.168.0.230
but this doesn't:
192.168.0.230/30 = 192.168.0.228 - 192.168.0.231 -> eucalyptus assigns 192.168.0.231 - 192.168.0.232
192.168.0.130/25 = 192.168.0.128 - 192.168.0.255 -> eucalyptus assigns 192.168.0.130 - 192.168.1.0
though you could argue that those are incorrect.
Eucalyptus apparently already has some crude support for this in net/vnetwork.c
So you *can* specify CIDR-style notation, like 192.168.0.128/25.
However if you specify a CIDR-style network that's not aligned to the first address, then it leads to a somewhat incorrect result:
so this leads to a correct result:
192.168.0.128/25 = 192.168.0.128 - 192.168.0.255 -> eucalyptus assigns 192.168.0.129 - 192.168.0.254
192.168.0.228/30 = 192.168.0.228 - 192.168.0.231 -> eucalyptus assigns 192.168.0.229 - 192.168.0.230
but this doesn't:
192.168.0.230/30 = 192.168.0.228 - 192.168.0.231 -> eucalyptus assigns 192.168.0.231 - 192.168.0.232
192.168.0.130/25 = 192.168.0.128 - 192.168.0.255 -> eucalyptus assigns 192.168.0.130 - 192.168.1.0
though you could argue that those are incorrect.