How do I add an additional SSH user with a non-standard home directory to Centos 7 AWS Machine?

Question

I have a CentOS 7 instance on AWS, and I connect using a .pem file. When I create a new user and follow the standard steps, (create .ssh directory, chmod 700 it, create authorized_keys file, copy the public key in, chmod 600 it. Instructions here: https://aws.amazon.com/premiumsupport/knowledge-center/new-user-accounts-linux-instance/ ) It works fine.

However when I create a new user with a non-standard home directory, I keep getting a permissions error. I tried creating a folder in the / directory, then when I noticed the perms didn't match the rest of the folders there, I created a new folder there using the root account, and then created a new user underneath that. (So basically /test/ was owned by root, /test/newuser/ was owned by new user.)

I followed the rest of the steps, but still, no luck.

I checked the /etc/ssh/sshd_config file and edited to:

AuthorizedKeysFile .ssh/authorized_keys /test/newuser/.ssh/authorized_keys

That didn't work either.

I should note that this setup works fine with amazon linux 2 images, but not with CentOS 7. Any suggestions?

Answer 1

Specify the non-standard home directory when creating the user with useradd command:

Create the base home directory

sudo mkdir /test

If SELinux is enabled and running in enforcing mode, you must relabel the files with correct SELinux context:

sudo semanage fcontext -a -t user_home_dir_t "/test(/.*)?"

Force SELinux to relabel the files on the fly

sudo restorecon -Rv /test

Then add users with custom home directories

sudo useradd -d /test/user1 user1
sudo useradd -d /test/user2 user2

These users will have correct permissions set for their home directories. More information on SELinux contexts and relabeling found here

Answer 2

Okay, I wanna be sure you have done the above, This solution is well tested on Centos 7 but not on AWS instance.

On your local server :
#Get the pub key
cat ~/.ssh/id_rsa.pub

On the remote server :

mkdir -p /test/newuser/.ssh/
chmod 700 /test/newuser/.ssh/
touch /test/newuser/.ssh/authorized_keys
chmod 600 /test/newuser/.ssh/authorized_keys
echo << EOF > /test/newuser/.ssh/authorized_keys
# ADD here  your ~/.ssh/id_rsa.pub already generated
EOF 
usermod -d /test/newuser test
chown root:root /test
chown -R test:test /test/*
#Edit/etc/ssh/sshd_config to add the above : 
Match User test
        AuthorizedKeysFile /test/newuser/.ssh/authorized_keys

Also could you copy the content of your sshd_config on the remote server :

grep -v '^#' /etc/ssh/sshd_config | sed '/^$/d'