Users gets deleted when cron job runs import_users.sh

[aswinkm-tc]

I installed aws-ec2-ssh on an ubuntu 16.04 server running on aws. The import_users.sh script imports the users from aws iam and setup the user environment. But after 10 minutes when the cron job runs the script again, it removes all the users imported. I have also noticed that, it doesn't remove local users created by me, as it should be.
I think the problem exist in the following code:
iam_users=$(get_clean_iam_users | sort | uniq)
sudo_users=$(get_clean_sudoers_users | sort | uniq)
local_users=$(get_local_users | sort | uniq)
intersection=$(echo ${local_users} ${iam_users} | tr " " "\n" | sort | uniq -D | uniq)
removed_users=$(echo ${local_users} ${intersection} | tr " " "\n" | sort | uniq -u)

[mvanbaak]

hum, strange. I have been using this code in production for a couple of months now and never saw what you describe here.

Can you check your server's logfiles for lines Deleted user <username> ?
It should have a line like that for every user

[aswinkm-tc]

I think its my bad, I did the configuration manually without running install.sh script and it works. I will close this issue.

[rbolkey]

This happened for me as well on Ubuntu 16.04 LTS; I think it's environmental.

The environment that cron runs in is:
HOME=/root
LOGNAME=root
PATH=/usr/bin:/bin
LANG=en_US.UTF-8
SHELL=/bin/sh
PWD=/root

But the aws command isn't on that path

$ which aws
/usr/local/bin/aws

[michaelwittig]

I think the problem is that this solution is not intended to work with Ubuntu. The demo uses Amazon Linux https://github.com/widdix/aws-ec2-ssh#demo-with-cloudformation and also our tests (https://github.com/widdix/aws-ec2-ssh/tree/master/test) use Amazon Linux only.

Is anyone interested in fixing all the Ubuntu issues? I'm not using Ubuntu at all. I'm an Amazon Linux user.

[mvanbaak]

I'm also not using Ubuntu, only Amazon Linux.

So to confirm for me:

• When you run the script manually, it works
• When cron runs the script, it doesn't work and deletes the users.
  Correct?

The thing about the PATH is a good one. On amazon linux the aws binary is in /usr/bin/aws so this could be the issue yes.

If it's not in the current PATH, we cannot use which or whereis to find the location.
This means we will have to create a list of possible locations of the binary, and check which one is executable and set that to a variable at the very top of the scripts :(

[michaelwittig]

I believe, if we change /etc/cron.d/import_users to:

SHELL=/bin/bash
PATH=/usr/bin:/bin:/usr/local/bin
*/10 * * * * root /opt/import_users.sh

it should work.

[mvanbaak]

Clearly you had your wake-up coffee, where I didn't.
Yes, that would work.

[michaelwittig]

☕️