solved: how to add and how to delete ip virtual in debian,ubuntu

how to delete virtual ip in debian, ubuntu:

ip addr del 1.1.1.2/32 dev eth2


ip addr add 1.1.1.1/24 dev eth2
ip addr add 1.1.1.2/24 dev eth2

https://serverfault.com/questions/486872/remove-ip-with-ip-command-in-linux