Christos Polydorou

The trigger to write this article was a troubleshooting session with a client that had built an automation process to deploy Windows Server and RedHat Enterprise Linux virtual machines on Azure. One of the steps of the provisioning process was to join the machine to the IaaS Active Directory Domain that was deployed on Azure and for this, an Active Directory account was required. Following the least previlege principle, the account used in the automation processes to join machines to the domain was a plain account that could indeed perform this operation. After some successfull joins however, the process started encountering errors when trying to join machines to the domain. As it turns out, the architects and security engineers had missed the fact that plain Active Directory accounts have the ability to only join a specific number of machines to the domain. When the automation reached that number, the process started to fail. To further troubleshoot the issue, we tried to join t...

Joining a linux machine to an Active Directory domain is an uncommon task, but I have run across it a few times. The increasing popularity of linux will sooner or later attract more windows administrators and users and more machines will be joined to Active Directory domains. Back in the day, to join the domain we had to do a lot of configuration file editing, many packages that had to be aligned and a lot of luck was a requirement! Fortunately, this process has been reduced to a handfull of commands! Let's see it in action. The first step is to install the necessary packages. yum install sssd realmd oddjob oddjob-mkhomedir adcli samba-common samba-common-tools krb5-workstation openldap-clients policycoreutils-python -y Give it some time to download and install the packages and their dependencies and you should end up with something similar to the below: Another requirement is that the machine has to be able to resolve the domain DNS records. Check your  /etc/...