When creating Linux containers for the purpos of joining them to an Active Directory Domain Controller, make sure the checkbox after the “Unprivileged Container” is unchecked. The “unprivileged container” checkbox is after the “Hostname” edit box. Unprivileged Linux containers won’t be able to join to an Active Directory. Essentially, I forgot to uncheck the “Unprivileged Container” and wasted hours of my time, but I consider time well spent when learning the hard way.
Proxmox has “Unprivileged Container” checked by default when creating a new Linux container. That option cannot be changed once a Linux container is created, so the Linux container will have to be deleted in order to start from scratch with “Unprivileged Container” unchecked.
Skip ahead to Long Version section for more details.
Who Is This Article For?
This article is for anyone who has experience with Proxmox. Proxmox is a Linux distribution and it comes with a web interface for running and managing virtual machines and Linux containers. This link will take you to the web page that explains how virtual machines and Linux containers work. The “long version” also mentions SSSD when I was troubleshooting issues while attempting to log into an Active Directory. System Security Services Daemon (SSSD, for short) is what enrolls a Linux client to an Active Directory. A “daemon” in Linux is another name for “services” in Windows that runs in the background. This article is intended for advanced Linux users only.
I wanted to see if I can implement Active Directory functionality without needing Windows Server operating system. A software called “Samba” lets me do just that, so I followed instructions on getting Samba’s Active Directory Domain Controller (AD-DC, for short) up and running. I set this up in a privileged Linux container. The reason why Linux containers need to have privileges is because when I did a search for “setresgid failed [Invalid argument]” (without quotes) in StartPage, I came across a page in GitHub titled Cannot log in with Active Directory users via SSSD on Proxmox #3153. That was when I created a new Linux container and I forgot to uncheck the “Unprivileged Container” checkbox. I did a lot of troubleshooting when I looked into
graysonpeddie.lan is my local domain name for my home network. This web page explains how to setup a Linux client for joining to a Samba domain. From what I have learned, if I execute an
id command in my Linux client:
uid=1451201106(gpeddie) gid=1451201104(grayson peddie) groups=1451201104(grayson peddie),1451200513(domain users)
According to the GitHub page that I linked earlier, the maximum user ID and group ID (UID and GID for short) is 65536 for an unprivileged Linux container. Within the issue page, the max UID and GID can be changed to 1000000000 or something higher. However, as this is for experienced Linux users who know the inner workings of Linux containers, the moral of the story is that “Unprivileged Container” needs to be unchecked in order for domain joining to work.
Bear in mind that privileged containers are not safe for businesses when it comes to attackers exploiting privileged Linux containers. And yes, it’s all about vulnerabilities and exploits when it comes to escaping Linux containers and causing damage to the host; however, for homelab purposes, a privileged Linux container is fine for my needs. If you are concerned about the security of Linux containers, spin up virtual machines instead of Linux containers in Proxmox. Of course, depending on your security hygiene, virtual machines can be as unsafe as privileged and unprivileged Linux containers if you do not have security precautions in place. For more details, learn more about privileged and unprivileged containers.
I watched the video about whether the ransomware can be stopped and I scrolled down through the comment section. While reading comments, some people are suggesting that we switch to Linux because Linux is more secure compared to Windows. That is true that Linux is inherently secure compared to Windows and Mac; however, what if I were to tell you that if you are running Arch Linux, Fedora, Ubuntu, Solaris, FreeBSD, OpenBSD, Haiku OS, or just about any other operating systems in our planet that you can still fall victim to phishing attacks? If we all switch to a different operating system on a basis that one is more secure compared to other operating systems, then we are forgetting about our weakest link.
Let me ask you again. Who or what is the weakest link in the cybersecurity chain? It’s not Windows; we are the ones that need education so we can protect ourselves online.
No anti-malware, anti-virus, and anti-ransomware programs will protect you against ransomware attacks. And Linux and BSD operating systems won’t protect you from phishing emails either. What we need is cybersecurity awareness training. Businesses should establish cybersecurity awareness training. Here’s one example that shows a video about cybersecurity awareness training from Burgi Technologies. The video starts with email, which talks about safeguarding your email such as phishing, email attachments, and spam. Do note though that an email address can be spoofed, so if you receive a phishing email and the email address in the From field ends in
@paypal.com and the email claims to be from PayPal, you should simply go to PayPal’s website and check what is going on in your PayPal account. Plus, the security awareness training talks about passwords, malware (don’t forget that malware can target Linux computers as well), public Wi-Fi, and even IoT, such as thermostats, Google Nest cameras, and even light bulbs. Even a router needs to be protected as well. And don’t forget about social engineering as well.
Remember what I mentioned about PayPal? Phishing attacks is one of them. They can even call you over the phone by impersonating that someone is your employer. They might say it’s urgent and they need access to the username and password so they can access the network resources so they can do harm. In other words, they can manipulate you into disclosing confidential or sensitive information.
Regarding security question and answers, it’s convenient if you forget your password, but put in your correct information and once an attacker can scour the Internet tin order to look for information, they can click the “reset password” link, fill in the answers to questions, and once everything is correct, they can then reset the password so you cannot access your account any longer. This is where a password manager comes in. Your password manager of choice can remember gibberish answers to questions. For example:
Question: What is your boyfriend’s name?
Answer: I would like to say thank you to my friend 68dagbbzpTmR5.
Question: What is your first car you owned?
Answer: My beautiful-looking car is my bicycle and I love jverw89.TmZr
Question: What is your mother’s maiden name?
A lack of honesty can safeguard your account against information gathering so they can do harm to your account. That’s why a password manager such as Bitwarden can come in handy so that a password manager can help remember your gibberish answers to security questions. And no, security questions is not a security feature. If I know so much about you and I know your email address, I can gather information about you and reset your password by answering security questions without your knowledge. I know this is scary, but don’t let that scare you if you are using a password manager.
To take it a step further, I also make use of unique email addresses as aliases. I do not use plus addressing or catchall because I can create email addresses for my own domain name. I use different email addresses for different sites that I sign up for. For example, I gave pizzahut(at)example(dot)com to Pizza Hut, uber(at)example(dot)com for Uber, walmart(at)example(dot)com for Wal-Mart, bestbuy(at)example(dot)com, and so on and so forth. Not only is this good for security, unique email addresses enhances my privacy. Sure, this is not part of cybersecurity awareness training as employees may not have the luxury of having more than 1 email addresses, but I did this in order to take security into my own hands so that I won’t become a weakest link in the cybersecurity chain. Even if businesses said that they took security seriously, if one of my unique email addresses have been compromised in a breach and ends up in Have I Been Pwned, not only should I change the password using my password manager, I can change my email address right away. Why? I did this in order to dodge spam and phishing emails. Because I make use of unique email addresses, I get very little to no spam each month. If I do get spam email messages that lands in my spam or inbox folder and one of my unique email addresses were listed in the To field, I can consider my email address compromised and can track who sold or give away my email address and change my email address or stop doing business with them at any time, immediately delete my compromised email address, and move on with my life.
Don’t let Linux users tell you that you should switch to Linux no matter how inherently secure Linux is. At the end of the day, no matter how much we need to keep our operating systems and software up to date, we still are the weakest link in the cybersecurity chain. We still need to educate everyone in order to stay safe online. Linux is not a be-all-end-all solution to our security problems.
(For my blog post, I want to focus on the audience regarding people who use Internet every single day and knows a lot about cybersecurity. Myself included.)
Imagine a scenario: you went to get your haircut and the place you went to requires you to enter an email address before you get your haircut. Why? Even if I do have a smartphone and I use Internet every single day, why must I put in my email address? For what purpose? To send spam? For businesses, they might say “we respect your privacy and take security seriously,” but in my mind, I would say that if an email gets compromised in a data breach, it’s more likely that those who are not tech-savvy are more likely to receive spam and phishing emails. Not thinking about security when using the Internet can lead to ransomware and identity theft. They might stop using the computer altogether because of fear of feeling unsafe online.
Okay, so I can imagine people asking…
What is ransomware?
So anyone who have not used the Internet before would then ask…
Okay, so what is malware? Oh, maybe I should click in the link. Oh, and what is a file?
Okay, I can imagine tech-savvy folks asking “what do you mean, ‘what is a file?’ Do you ever know how to use a computer before?” How can we guide people who does not use Internet every single day, let alone not knowing “what is an Internet?”
What is an operating system? Windows? Mac? Linux? What is an email address? What is a “file?” See where I’m going with? What is Android? iPhone? iOS? How do I manage files and folders in my computer? How do I check my email? I hope you get my point.
So back to the topic about email address requirement, people who have no plans to educate themselves regarding security and privacy should not have an email address and should not be using the Internet. Even a smartphone can be very complex compared to a cell phone that only make and receive phone calls and nothing else. Let alone how to send and read text messages. And yes, I’m talking about people who use cell phones with no capability for browsing the Internet. Not even Firefox, Chrome, or Safari.
Okay, so you say that your 90-year-old grandmother knows how to use the Internet, takes care of security themselves, and I should not overly-generalize myself. Well, that’s great. People should be educated regarding the implications regarding cyber attacks and how to protect themselves; however, as long as people out there (Demographics of Cybercrime Report) do not take their time to educate and protect themselves, businesses should not require them to have an email address when they check in. Even dentists should make email address requirement optional as well. Even though I have close to 200 email addresses (one email address per site with no plus addressing and no catchall for my domain), I do not want to enter my email address if I do not want to for privacy and security reasons.
Businesses say “we take security and privacy seriously,” yet businesses do not take their time to harden and patch their systems over time. Of course, training employees regarding how to protect themselves against phishing emails is a very important part of having a security culture for businesses. But then again, an email address would be a requirement for businesses for getting your customers to setup an account online, but in a physical world where people simply walk in, as long as people do not use the Internet and do not plan to educate themselves, an email address should not be a requirement. At all.
I have been watching a couple of YouTube videos of people who want a computer in one room (such as a wiring closet) and a keyboard, video, and mouse (KVM) in a home office. To give you an idea of what I’m talking about, I want to post links to YouTube videos.
Embedding YouTube or Odysee videos will insert a tracking cookie in users’ personal computers. As a citizen of the US, I need to follow GDPR if European visitors visit my website. I don’t like and want to talk to lawyers to be honest. 🤣😀
As for the video from Linus Tech Tips, I would much rather have a couple of computers rather than single computer that can house a couple of virtual machines running desktop OSes such as Linux and Windows just to make it easier for me. So yeah, a virtual machine is a computer within a computer that can serve different purposes such as running Ubuntu within Windows using VirtualBox or by running Windows OS in a Linux host using KVM or Xen.