Migrating in plesk shows an error. Checking the IP address pool in plesk show this
2607:5200:1800:1000:226:18ff:fe24:4e35 (dedicated)
Trying to remove it produces an error:
Error: Cannot remove the IP address 2607:5200:1800:1000:226:18ff:fe24:4e35 because it is the last IP address present on a network interface.
Disable IPV6 – http://wiki.centos.org/FAQ/CentOS6#head-d47139912868bcb9d754441ecb6a8a10d41781df
Restart plesk and re-read the IP address pool in plesk > Tools and Settings > IP Addresses > Re-read IP’s