Rename a username , groupname and its homedirectory with usermod

Rename user 7777777 ’s name, groupname and homedir to 88888888 with usermod

root@server1 [/home]# useradd 7777777
root@server1 [/home]#
root@server1 [/home]# grep 7777777 /etc/passwd
7777777:x:32147:32148::/home/

7777777:/bin/bash
root@server1 [/home]#
root@server1 [/home]# grep 7777777 /etc/group
7777777:x:32148:
root@server1 [/home]#
root@server1 [/home]# usermod -d /home/88888888 7777777
root@server1 [/home]#
root@server1 [/home]# grep 7777777 /etc/passwd
7777777:x:32147:32148::/home/88888888:/bin/bash
root@server1 [/home]#

************************************************************************************************************
root@server1 [/home]# rm -fr /home/7777777/        OR  you can mv /home/7777777 /home/88888888, if you want
************************************************************************************************************

root@server1 [/home]# usermod -l 88888888 7777777
failed to rename mailbox: File exists
root@server1 [/home]#

root@server1 [/home]# grep 7777777 /etc/passwd

root@server1 [/home]# grep 88888888 /etc/passwd
88888888:x:32147:32148::/home/88888888:/bin/bash
root@server1 [/home]#

root@server1 [/home]# groupmod -n 88888888 7777777
root@server1 [/home]#

root@server1 [/home]# grep 7777777 /etc/group

root@server1 [/home]#
root@server1 [/home]# grep 88888888 /etc/group
88888888:x:32148:
root@server1 [/home]#