You can add the command in your system initial script. So every time the system startup will run this command.
e.g. for your reference
Thank you.
I tried the URL method you showed, but couldn't fix the ip address.
I solved it in another way.
Added the ifconfig command to the line above exit0 in /etc/rc.local.
$ vi /etc/rc.local
-------------------------------------------------- --------
::
::
#set printk to 7 to dump kernel massage to console
echo 7> / proc / sys / kernel / printk
#set ip address
ifconfig eth0 <ip address> netmask <netmask>
exit0
-------------------------------------------------- --------