[CentOS] I cannot add user to a group permanently

[Gordon Messmer]

On 10/16/2016 04:57 AM, Xuwen Fang wrote:
> I'm using a centos 7 server. I tried to add my own user to group 'apache'
> and it works temporarily. When I ssh to it later, I found my user not a
> member of group 'apache'. What's wrong with it?


Are you using "newgrp"?  That tool starts a new session wherein the user 
is a member of a new group.  Permanent addition should be "usermod -a -G 
$group $user"