I am stuck with creating users with Cloud-Config.
Did anyone succeed and can share a .yaml gist to create a new user with ssh-authorized-keys and ability to sudo?
This article on DigitalOcean runs through doing some of the most common initial tasks using cloud-config files.
Setting up a new sudo user would look like this:
#cloud-config
users:
- name: username
ssh-authorized-keys:
- ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQCv60WjxoM39LgPDbiW7ne3gu18q0NIVv0RE6rDLNal1quXZ3nqAlANpl5qmhDQ+GS/sOtygSG4/9aiOA4vXO54k1mHWL2irjuB9XbXr00+44vSd2q/vtXdGXhdSMTf4/XK17fjKSG/9y3yD6nml6 user#example.com
sudo: ['ALL=(ALL) NOPASSWD:ALL']
groups: sudo
shell: /bin/bash
Of course, replace the ssh key with your public key.
Related
I am attempting to have playbooks that run once to set up a new user and disable root ssh access.
For now, I am doing that by declaring all of my inventory twice. Each host needs an entry that accesses with the root user, used to create a new user, set up ssh settings, and then disable root access.
Then each host needs another entry with the new user that gets created.
My current inventory looks like this. It's only one host for now, but with a larger inventory, the repetition would just take up a ton of unnecessary space:
---
# ./hosts.yaml
---
all:
children:
master_roots:
hosts:
demo_master_root:
ansible_host: a.b.c.d # same ip as below
ansible_user: root
ansible_ssh_private_key_file: ~/.ssh/id_rsa_infra_ops
masters:
hosts:
demo_master:
ansible_host: a.b.c.d # same ip as above
ansible_user: infraops
ansible_ssh_private_key_file: ~/.ssh/id_rsa_infra_ops
Is there a cleaner way to do this?
Is this an anti-pattern in any way? It is not idempotent. It would be nice to have this run in a way that running the same playbook twice always has the same output - either "success", or "no change".
I am using DigitalOcean and they have a functionality to have this done via a bash script before the VM comes up for the first time, but I would prefer a platform-independent solution.
Here is the playbook for setting up the users & ssh settings and disabling root access
---
# ./initial-host-setup.yaml
---
# References
# Digital Ocean recommended droplet setup script:
# - https://docs.digitalocean.com/droplets/tutorials/recommended-setup
# Digital Ocean tutorial on installing kubernetes with Ansible:
# - https://www.digitalocean.com/community/tutorials/how-to-create-a-kubernetes-cluster-using-kubeadm-on-debian-9
# Ansible Galaxy (Community) recipe for securing ssh:
# - https://github.com/vitalk/ansible-secure-ssh
---
- hosts: master_roots
become: 'yes'
tasks:
- name: create the 'infraops' user
user:
state: present
name: infraops
password_lock: 'yes'
groups: sudo
append: 'yes'
createhome: 'yes'
shell: /bin/bash
- name: add authorized keys for the infraops user
authorized_key: 'user=infraops key="{{item}}"'
with_file:
'{{ hostvars[inventory_hostname].ansible_ssh_private_key_file }}.pub'
- name: allow infraops user to have passwordless sudo
lineinfile:
dest: /etc/sudoers
line: 'infraops ALL=(ALL) NOPASSWD: ALL'
validate: visudo -cf %s
- name: disable empty password login for all users
lineinfile:
dest: /etc/ssh/sshd_config
regexp: '^#?PermitEmptyPasswords'
line: PermitEmptyPasswords no
notify: restart sshd
- name: disable password login for all users
lineinfile:
dest: /etc/ssh/sshd_config
regexp: '^(#\s*)?PasswordAuthentication '
line: PasswordAuthentication no
notify: restart sshd
- name: Disable remote root user login
lineinfile:
dest: /etc/ssh/sshd_config
regexp: '^#?PermitRootLogin'
line: 'PermitRootLogin no'
notify: restart sshd
handlers:
- name: restart sshd
service:
name: sshd
state: restarted
Everything after this would use the masters inventory.
EDIT
After some research I have found that "init scripts"/"startup scripts"/"user data" scripts are supported across AWS, GCP, and DigitalOcean, potentially via cloud-init (this is what DigitalOcean uses, didn't research the others), which is cross-provider enough for me to just stick with a bash init script solution.
I would still be interested & curious if someone had a killer Ansible-only solution for this, although I am not sure there is a great way to make this happen without a pre-init script.
Regardless of any ansible limitations, it seems that without using the cloud init script, you can't have this. Either the server starts with a root or similar user to perform these actions, or the server starts without a user with those powers, then you can't perform these actions.
Further, I have seen Ansible playbooks and bash scripts that try to solve the desired "idempotence" (complete with no errors even if root is already disabled) by testing root ssh access, then falling back to another user, but "I can't ssh with root" is a poor test for "is the root user disabled" because there are plenty of ways your ssh access could fail even though the server is still configured to allow root to ssh.
EDIT 2 placing this here, since I can't use newlines in my response to a comment:
β.εηοιτ.βε responded to my assertion:
"but "I can't ssh with root" is a poor test for "is the root user disabled" because there are plenty of ways your ssh access could fail even though the server is still configured to allow root to ssh
with
then, try to ssh with infraops and assert that PermitRootLogin no is in the ssh daemon config file?"
It sounds like the suggestion is:
- attempt ssh with root
- if success, we know user/ssh setup tasks have not completed, so run those tasks
- if failure, attempt ssh with infraops
- if success, go ahead and run everything except the user creation again to ensure ssh config is as desired
- if failure... ? something else is probably wrong, since I can't ssh with either user
I am not sure what this sort of if-then failure recovery actually looks like in an Ansible script
You can overwrite host variables for a given play by using vars.
- hosts: masters
become: 'yes'
vars:
ansible_ssh_user: "root"
ansible_ssh_private_key_file: "~/.ssh/id_rsa_infra_ops"
tasks:
You could only define the demo_master group and alter the ansible_user and ansible_ssh_private_key_file at run time, using command flags --user and --private-key.
So with an host.yaml containing
all:
children:
masters:
hosts:
demo_master:
ansible_host: a.b.c.d # same ip as above
ansible_user: infraops
ansible_ssh_private_key_file: ~/.ssh/id_rsa_infra_ops
And run on - hosts: master, the first run would, for example be with
ansible-playbook initial-host-setup.yaml \
--user root \
--private-key ~/.ssh/id_rsa_root
When the subsequent runs would simply by
ansible-playbook subsequent-host-setup.yaml
Since all the required values are in the inventory already.
I added another user's public ssh-key to my dokku server, but they can't login using ssh root#appname.com.
I can see their ssh-key in authorized_keys and also if I run sshcommand list dokku or sshcommand list root.
I have checked in the sudoers config, and it seems that all ssh-keys are given root permissions:
$ cat sudoers
/...
# User privilege specification
root ALL=(ALL:ALL) ALL
I am using the dokku-acl plugin, but haven't found anything in the docs that would help.
The server is an Aliyun ECS (China).
Feel like I am missing something simple. Any advice is very much appreciated!
root ssh access and dokku ssh access are governed separately. The user's public key should be added as is to the /root/.ssh/authorized_keys file, whereas the /home/dokku/.ssh/authorized_keys file should only be managed by the subcommands of the ssh-keys plugin (included with Dokku).
You may wish to remove the entries from both files manually, then add the entries back as described above. For dokku user access - which would grant the ability to push code as well as perform remote commands via ssh dokku#host $command - you can use the command dokku ssh-keys:add to add a specific user:
echo "PUBLIC_KEY_CONTENTS" | dokku ssh-keys:add some-user-name
I am using Ansible to provision a Vagrant environment. As part of the provisioning process, I need to connect from the currently-provisioning VM to a private external repository using an ssh key in order to use composer to pull in modules for an application. I've done a lot of reading on this before asking this question, but still can't seem to comprehend what's going on.
What I want to happen is:
As part of the playbook, on the Vagrant VM, I add the ssh key to the private repo to the ssh-agent
Using that private key, I am then able to use composer to require modules from the external source
I've read articles which highlight specifying the key in playbook execution. (E.g. ansible-play -u username --private-key play.yml) As far as I understand, this isn't for me, as I'm calling the playbook via Vagrant file. I've also read articles which mention ssh forwarding. (SSH Agent Forwarding with Ansible). Based on what I have read, this is what I've done:
On the VM being provisioned, I insert a known_hosts file which consists of the host entries of the machines which house the repos I need:
On the VM being provisioned, I have the following in ~/.ssh/config:
Host <VM IP>
ForwardAgent yes
I have the following entries in my ansible.cfg to support ssh forwarding:
[defaults]
transport = ssh
[ssh_connection]
ssh_args=-o ForwardAgent=yes -o ControlMaster=auto -o ControlPersist=60s -o ControlPath=/tmp/ansible-ssh-%h-%p-%r
[privilege_escalation]
pipelining = False
I have also added the following task to the playbook which tries to
use composer:
- name: Add ssh agent line to sudoers
become: true
lineinfile:
dest: /etc/sudoers
state: present
regexp: SSH_AUTH_SOCK
line: Defaults env_keep += "SSH_AUTH_SOCK"
I exit the ansible provisioner and add the private key on the provisioned VM to the agent via a shell provisioner (This is where I suspect I'm going wrong)
Then, I attempt to use composer, or call git via the command module. Like this, for example, to test:
- name: Test connection
command: ssh -T git#github.com
Finally, just in case I wasn't understanding ssh connection forwarding correctly, I assumed that what was supposed to happen was that I needed to first add the key to my local machine's agent, then forward that through to the provisioned VM to use to grab the repositories via composer. So I used ssh-add on my local machine before executing vagrant up and running the provisioner.
No matter what, though, I always get permission denied when I do this. I'd greatly appreciate some understanding as to what I may be missing in my understanding of how ssh forwarding should be working here, as well as any guidance for making this connection happen.
I'm not certain I understand your question correctly, but I often setup machines that connect to a private bitbucket repository in order to clone it. You don't need to (and shouldn't) use agent forwarding for that ("ssh forwarding" is unclear; there's "authentication agent forwarding" and "port forwarding", but you need neither in this case).
Just to be clear with terminology, you are running Ansible in your local machine, you are provisioning the controlled machine, and you want to ssh from the controlled machine to a third-party server.
What I do is I upload the ssh key to the controlled machine, in /root/.ssh (more generally $HOME/.ssh where $HOME is the home directory of the controlled machine user who will connect to the third-party server—in my case that's root). I don't use the names id_rsa and id_rsa.pub, because I don't want to touch the default keys of that user (these might have a different purpose; for example, I use them to backup the controlled machine). So this is the code:
- name: Install bitbucket aptiko_ro ssh key
copy:
dest: /root/.ssh/aptiko_ro_id_rsa
mode: 0600
content: "{{ aptiko_ro_ssh_key }}"
- name: Install bitbucket aptiko_ro ssh public key
copy:
dest: /root/.ssh/aptiko_ro_id_rsa.pub
content: "{{ aptiko_ro_ssh_pub_key }}"
Next, you need to tell the controlled machine ssh this: "When you connect to the third-party server, use key X instead of the default key, and logon as user Y". You tell it in this way:
- name: Install ssh config that uses aptiko_ro keys on bitbucket
copy:
dest: /root/.ssh/config
content: |
Host bitbucket.org
IdentityFile ~/.ssh/aptiko_ro_id_rsa
User aptiko_ro
I want to use a public aws keypair .pem file for running ansible playbooks. I want to do this without changing my ~/.ssh/id_rsa.pub and I can't create a new keypair from my current ~/.ssh/id_rsa.pub and apply it to the ec2 instances I am trying to change.
$ ansible --version
ansible 1.9.6
configured module search path = None
Here is my hosts file (note that my actual ip is replaced with 1.2.3.4). This is probably the issue since I need a way to set a public key variable and use that:
[all_servers:vars]
ansible_ssh_private_key_file = ./mykeypair.pem
[dashboard]
1.2.3.4 dashboard_domain=my.domain.info
Here is my playbook:
---
- hosts: dashboard
gather_facts: False
remote_user: ubuntu
tasks:
- name: ping
ping:
This is the command I am using to run it:
ansible-playbook -i ./hosts test.yml
It results in the following error:
fatal: [1.2.3.4] => SSH Error: Permission denied (publickey).
while connecting to 1.2.3.4:22
There is no problem with my keypair:
$ ssh -i mykeypair.pem ubuntu#1.2.3.4 'whoami'
ubuntu
What am I doing wrong?
Ok little mistakes I guess you can't have spaces in host file variables and need to define the group you are applying the vars to. This hosts file works with it all:
[dashboard:vars]
ansible_ssh_private_key_file=./mykeypair.pem
[dashboard]
1.2.3.4 dashboard_domain=my.domain.info
I have come across this and all what I had to do was to run the below
#ssh-agent bash
#ssh-add ~/.ssh/keypair.pem
How do I setup passwordless ssh between nodes on AWS cluster
Following steps to setup password less authentication are tested thoroughly for Centos and Ubuntu.
Assumptions:
You already have access to your EC2 machine. May be using the pem key or you have credentials for a unix user which has root permissions.
You have already setup RSA keys on you local machine. Private key and public key are available at "~/.ssh/id_rsa" and "~/.ssh/id_rsa.pub" respectively.
Steps:
Login to you EC2 machine as a root user.
Create a new user
useradd -m <yourname>
sudo su <yourname>
cd
mkdir -p ~/.ssh
touch ~/.ssh/authorized_keys
Append contents of file ~/.ssh/id_rsa.pub on you local machine to ~/.ssh/authorized_keys on EC2 machine.
chmod -R 700 ~/.ssh
chmod 600 ~/.ssh/*
Make sure sshing is permitted by the machine. In file /etc/ssh/sshd_config, make sure that line containing "PasswordAuthentication yes" is uncommented. Restart sshd service if you make any change in this file:
service sshd restart # On Centos
service ssh restart # On Ubuntu
Your passwordless login should work now. Try following on your local machine:
ssh -A <yourname>#ec2-xx-xx-xxx-xxx.ap-southeast-1.compute.amazonaws.com
Making yourself a super user. Open /etc/sudoers. Make sure following two lines are uncommented:
## Allows people in group wheel to run all commands
%wheel ALL=(ALL) ALL
## Same thing without a password
%wheel ALL=(ALL) NOPASSWD: ALL
Add yourself to wheel group.
usermod -aG wheel <yourname>
This may help someone
Copy the pem file on the machine then copy the content of pem file to the .ssh/id_rsa file you can use bellow command or your own
cat my.pem > ~/.ssh/id_rsa
try ssh localhost it should work and same with the other machines in the cluster
how I made Paswordless shh work between two instances is the following:
create ec2 instances – they should be in the same subnet and have the same security group
Open ports between them – make sure instances can communicate to each other. Use the default security group which has one rule relevant for this case:
Type: All Traffic
Source: Custom – id of the security group
Log in to the instance you want to connect from to the other instance
Run:
1 ssh-keygen -t rsa -N "" -f /home/ubuntu/.ssh/id_rsa
to generate a new rsa key.
Copy your private AWS key as ~/.ssh/my.key (or whatever name you want to use)
Make sure you change the permission to 600
1 chmod 600 .ssh/my.key
Copy the public key to the instance you wish to connect to passwordless
1 cat ~/.ssh/id_rsa.pub | ssh -i ~/.ssh/my.key ubuntu#10.0.0.X "cat >> ~/.ssh/authorized_keys"
If you test the passwordless ssh to the other machine, it should work.
1 ssh 10.0.0.X
you can use ssh keys like described here:
http://pkeck.myweb.uga.edu/ssh/