Category Archives: DevOps

DevOps is not one tool and not one job title with a fixed meaning everywhere. In practice, a strong DevOps engineer is someone who helps teams deliver software faster and more reliably by improving systems, automation, visibility, and collaboration.

1. Linux and System Fundamentals

Most modern infrastructure still depends on strong operating system knowledge. Understanding processes, services, files, networking, permissions, and system diagnostics gives you the base to troubleshoot real production problems.

2. Scripting and Automation

Manual work does not scale well. Shell scripting, Python, or similar tools help automate deployment, validation, backups, reporting, and environment setup.

3. CI/CD

Continuous integration and continuous delivery pipelines are central to modern delivery. A DevOps engineer should understand testing flow, artifact creation, deployment stages, rollback strategies, and release reliability.

4. Containers and Orchestration

Docker and Kubernetes matter because they standardize packaging and deployment. You do not need to use every advanced feature, but you should understand the operational model behind them.

5. Cloud Infrastructure

AWS, GCP, and Azure all provide different services, but the underlying engineering ideas remain similar: scalable compute, storage, networking, IAM, and monitoring.

6. Observability

Logs, metrics, traces, and alerts are what turn a running system into an understandable system. You cannot improve reliability if you cannot see what is happening.

7. Communication and Ownership

This is often underestimated. DevOps engineers work across teams, so they must explain tradeoffs, reduce friction, and take responsibility for delivery quality, not just infrastructure syntax.

Final Thoughts

A strong DevOps engineer is not simply a person who knows many tools. It is a person who can use the right tools to reduce operational risk and improve the speed and confidence of delivery.

Hello again! Today’s class is metal as a service MAAS so we’ve been doing a number of classes lately on these different services, we’ve talked about software as a service we’ve talked about infrastructure as a service, and we have talked about platform as a service. Now when you’re talking about these services by far the most popular solution out there is software as a service that is where you basically you go out and you lease software from companies and the software is all run on their server so we’re talking about software as a service think about things like Google Docs think about things like Salesforce the software is not installed on your local computer.

Its installed on their servers and you access that somehow these are either through a web browser or through some type of a terminal connection something like that tied by the infrastructure as a service basically when your your infrastructure all those things that you would buy and install in your premises you no longer actually own anymore.

So think about your telephone systems companies you should spend $50 thousand on their telephone system and that telephone system was installed in their premises and they owned it now you can get hosted voice over IP solutions such as on sip you get hosted firewall solutions you can have hosted server rooms why have your own servers when you can go to Amazon Web Services and simply spin up a number of virtual services on their platform so that is infrastructure as a service.

We then talked about platform as a service platform as a service is where you create your web apps and then you are looking for some place to host them so the basic idea is think about a shared hosting web plan you create your web site you create your web application and then you simply upload that to GoDaddy or one in one servers their servers have PHP installed their servers have my sequel installed their servers have Ruby or Perl or any of these other scripting languages that you need all that you have to worry about is your application of course that gets much more complicated once you go over to Google App Engine and some of the more and more advanced things but that’s the the basic concept so now we’re getting to basically probably the last service that I will be talking about is metal as a service now this is one of those really really really cool ideas that actually it is pretty cutting-edge I’m not sure if it’s bleeding edge but it’s pretty cutting edge so some of you guys looking to create businesses out there really should listen to what I’m talking about right now because it really is a good business opportunity right now because not very many people actually offer this service so when we’re talking about metal as a service what we are literally talking about is providing the server hardware as a service to clients so this is not the same thing as what you would normally think about with cloud computing or virtualization where you install a hypervisor onto a server and then they spin up some kind of a instance of a server and this isn’t the same thing as a dedicated server so for thanhguyensite.net and a couple of other things that I do we rent a dedicated server from a company called one and one comm with that I get a specific server 12 gigs of ram quad core processor blah blah blah.

With a certain version of Linux on it and then from that point I can configure up but with that when you are purchasing something like a dedicated server you have to use whatever operating systems are provided by the provider so with one and one com if you go with them you can use like Server 2008 or Server 2012 Fedora sent OS if you wanted to use something else tough luck if you wanted to use freebsd on one of these services that you couldn’t do it if you wanted to install a hypervisor on Twenties dedicated services servers you couldn’t do it the reason is is because although you’re renting the dedicated server it has to have a bare minimum installation on it before you are actually able to get access to it the cool thing with metal as a service it is the concept is that you are literally renting the physical box with nothing else on it so this is where you would go to a provider and you would literally rent it would be a quad-core xeon processor with so much RAM so much hard drive and that’s it there would not necessarily be sent OS on it there were not necessarily be windows on it there wouldn’t necessarily be anything on it.

You are literally renting the metal as a service so basically now instead of having to have your own server rooms with your own equipment your own server racks your own HVAC you’re all redundant to power supply and your ups and all of that kind of stuff you can have the same thing sitting in somebody else’s server room so they are renting to you the metal as a service now that you may be wondering why why would you bother with that if you can get virtual servers if you can use infrastructure as a service if you can even get dedicated servers why would you run want to rent or lease the bare metal as a service well as you go through with your companies.

If you have a startup company or if you have a technology company and you start growing what, you are going to find is no matter what operating system distribution you use. It is probably not going to be optimized for whatever it is you’re doing so you know we all know with Windows we all know with Windows. Windows hogs up a lot of extra resources to do things most of us really truly don’t care about it we’ll be happy if it did it but a lot of people don’t realize is even with Linux.

Even with Linux there are resources that are used there are security vulnerabilities that are opened up simply because when you install the default installation of whatever Linux you’re going to be using it installs a base level of applications and services and a lot of times you don’t need that so imagine if you were a company where you want to spin out a lot of database servers and you want those database servers to run at the absolute optimum the fastest they can possibly run well you may want to go in to a distribution of an operating system and literally rip out all the crap that you don’t want you don’t need notepad you don’t need tar you don’t need a lot of these these things you just need that server to run as fast as possible to do a specific task possibly do something like a database server because this becomes very important especially when you start dealing with larger companies that are dealing with a larger load on their servers because when you rip out all of the crap you don’t need on it on a servers operating system.

You can gain efficiencies now this is not you’re not going to probably speed up the server by 200% or 500% or a thousand percent right that’s not what what the target you’re going to hit you may be able to actually speed up the server though by something like five percent now for you especially if you haven’t dealt with real server rooms if you haven’t dealt with real loads on servers optimizing an operating system we get five percent improvement probably doesn’t sound like a big deal but with companies if you if you have 20 servers up and running or 40 servers up and running a five percent increase in speed can be very very very very very very very significant so with these companies they may be looking to optimize the things like I say the operating systems that will be installed how all this will be configured how all this will be managed and so all they want is the bare metal they want the server they want the hard drives they want the RAM.

They want the CPU but they don’t want anybody else to mess with the rest of it they want to be able to build this thing from the ground up and again there can be a lot of reasons for this nowadays things like again efficiency making sure that the resources on the server are optimized but also issues such as compliance so compliance is becoming a bigger and bigger deal within the the corporate world what compliance means is that you are running your IT systems to certain specifications for security and reliability so as more and more companies start using cloud computers and servers and all that to run the infrastructure of their business they have to make sure that that infrastructure is reliable enough for their industry now one of the problems if you go out and you use a standard instance of an operating system or you use a standard load of an operating system from one of these providers is you don’t necessarily know all the security flaws you haven’t necessarily been able to sit down and do penetration test and do hardening testing and do all of those things so when you when you are leasing let’s say from 1 + 1 , dedicated server you can’t guarantee that this is that the the server operating system that has been installed is as hardened as it should be.

Now again for somebody like me I don’t care again do good backups and you should be fine for and this is one of the things you have to think about for 98% of the business population this type of concept doesn’t matter but for that 2% it is very very very important it is very important that they know that whatever operating system and software that’s going to be installed in that server it lives up to certain specifications so that’s why they would want to be able to rent that that bare metal as a service so metal as a service now one of the questions that you’re going to be coming up in with thanh’s you’re gonna be saying work and got me saying.

Well Thanh uh I don’t understand how you would interact with metal as a service then because you know when we think about dealing with these virtual computers when we think about dealing with it with cloud computers and all that we have a basic interface to deal with so basically again if you get a dedicated server you get a virtual private server they spin up the operating system and then they give you the login credentials so basically the company that you’re buying the service from they have already installed the instance of the operating system they’ve already created the first user account they then give you that information for that first user account and then you can figure it out.

However it is you want so the question you may be asking say well I don’t I don’t understand that because if you’re literally renting the metal and the metal let’s say five states away well wait a minute but there’s no operating system to interact with and the metals five states away so you don’t want to drive there so so I don’t understand how you would configure it or work with it well one of the cool things and not really new but but they’re they’re coming too more into vogue is something called IPP KVM switches so kate.

KVM switches been around for forever long far longer than i’ve been in the computer industry keyboard video mouse switches so what these are generally when you’re dealing with a server rack is you plug all the servers in the rack into one KVM switch and then you can press a button then when you press that button that gives you access to the server from one keyboard video and mouse combination so you have a monitor you have a keyboard and mouse and you say oh I need to deal with the wit server – and you just hit the server – button and server – pops up oh I need to deal with server 10 you click the server 10 button and the server 10 pops up well with KVM they now have IP k via what this means is that you can deal with that server from the basic input/output so the basic video keyboard and mouse and you can do that over an IP connection so you can either open that up through a web browser and be able to log in or you can open it up through some kind of terminal session or or some kind of application so basically you can be sitting in your in your office five states away from this bare metal the company that you’re dealing with will plug in the KVM switch and whatever else and then basically you can hit the on there.

They can hit the on button or you may have some kind of remote wait at the on button and from there it will literally load into a BIOS screen then from there depending on what the the service provider has for you you can go and you can install your your your your operating system and do all of your configurations but literally you have remote access to the lowest level of that server so you could literally reboot that server and go into the BIOS and change BIOS configuration settings you literally have that ability whether you’re five states away or you know on an entirely different continent now especially with PDUs so the the power distribution units basically what most people will call surge protectors even those have remote access so that you can do things like power cycle the server because again the question where you’re like well Thanh I don’t understand if if you have metal as a service.

If you have that metal and you do something wrong and it freezes up how do you force it to restart because again you know you’re installing operating systems you’re doing all kind of wacky stuff sometimes it’ll freeze and if you have access to the metal what are you going to do well with these surge protectors these power distribution units you can actually power cycle them again remotely so this is the cool stuff with metal as a service I think this is going to become a much more prominent thing right now this is one of those things that it is offered by companies you don’t see it around a lot but it is something that you should be looking at and you should be thinking about because again this way you can have you you can have your own custom servers that have been hardened up to your specifications but they are sitting in somebody else’s data center you don’t have to worry about it just like with all these commoditized items it is less expensive for you to be able to rent this service from somebody else that can have a thousand or five thousand or twenty thousand of these servers up and running basically they can have five or ten technicians running around making sure all the metal is doing with metal supposed to do versus if you had servers in each one of your individual offices and having people run around and deal with that kind of stuff so that’s the basic concept of metal as a service again all it is at the end of the day is you are literally leasing or renting that bare metal so you’ve got a server with absolutely no operating system on it.

That is what you’re leasing that allows you to do a lot of really cool sexy amazing cool stuff um and with the modern technology like I say it’s actually very very very doable today it’s one of those things when you got to start thinking we think about the cloud I mean that’s a whole one of the problems with us old technicians right is we’re used to touching stuff we like you know when we work on computers we’re used to keyboards we’re used to like plugging away and we’ve got the server in front of us and we got the router in front of us we got all this stuff in front of us so like mentally we think about all this equipment like being in our server room being in our office being in our facility and so what you have to realize is in this modern world that we’re in you can have the exact same functionality that you would have if the equipment was in your building but it can be somewhere else it can be provisioned given to you very quickly it can be given to you very inexpensively and you can be provided as securely or more securely than what you could do yourself again a lot of people you know I’m starting to talk you know talking about things like metal as a service and everybody gets worried about security everybody’s like oh how do I how do I know Thanh.

How do I know my servers are going to be secure how do I know that data center is going to be secure well one you do something called due diligence you you actually make sure that the company that you’re dealing with is a legitimate company you probably if you’re going to be running your business office stuff you should fly out to their data center at least once to actually take a look at it make sure they’ve got all the security stuff and all that but beyond that what a lot of people don’t realize is how in secure their facilities actually are they always worry about how insecure the cloud provider is and they somehow completely ignore just the crappy crappy crappy crappy crappy security that they have on their facility again I’m here in Baltimore Maryland in the Baltimore City.

We have an incredibly high crime rate and so one of the real problems that you have is you can have antivirus on your servers you can have your firewalls on your servers you can of your intrusion detection on the servers you can have your ups on the servers and some crackhead could break into your building literally rip the server out of server rack and walk away with it and try to sell for 25 bucks to the local pawn shop and when they can’t sell it at the local pawn shop then they’ll get pissed and they’ll just throw it in a ditch and keep walking again that’s the nice thing with these data centers at least with that kind of physical security you would be surprised many times they have much much much much better physical security in the rest of this then then you have take a real honest hard look at the security in your facility and if you’re honest about it you probably know that it’s it’s probably pretty bad it’s probably probably probably your servers would be better off in some kind of hosted solution so that’s all there is for from metal as a service.

I enjoy taking this class and look forward to see you the next one you.

In this post I will share experience using linux command, and was we can do and play with a operating system for Developer, or shorter is Linux. You don’t need to know more about this, I will show you how you can create funny program with some Linux command, what you can’t do in Windows.

1. Linux updates and upgrades do not require you to reboot

Re-booting after every software installation or update is very annoying in Windows. I keep wondering why this is not necessary in Linux, but on Windows is rule of tumb – every installation is asking you to re-boot, or after you download the Upgrades annoying window pop up and say – will reboot in 10 minutes, save your work. This is really annoying.

With Linux all you need to do is run : sudo apt update

Then have a cup of coffee until it update your computer.

2. No need to install drivers every time you plug in your computer USB device

OK, I understand that there are custom devices which use uncommon drivers like printers, cameras, etc, but why on earth every time you plug in Windows simple mass storage disk drive, or USB-Serial converter, or Mouse, or Keyboard – devices which are standard and are embedded in every Windows OS after W98 it ALWAYS ask for drivers which are already there? Why on Linux I plug the external HHD or Flash drive and it automatically mounts on my computer and I can work with it, while Windows is asking me for drivers and several minutes scans and show me different windows with warnings and Continue buttons like I’m doing something scaring which may ruin my OS?

3. You can move image/boot-able drive between machines without need for reinstall

Yes! this is something windows users can’t imagine is possible! I do remember back in the dark ages Windows asked me to re-install after I have upgraded the RAM memory size! Now imagine you get your Windows boot-able HDD and plug it on other computer, will it boot? no way!

4. system config in files not registers mess

Now this is one of the most annoying WIndows features – after several months of installing and removing software your registers and windows/system directory becomes so bloated with shared DLLs and mess that some people start making money by writing registry cleaning software!

5. You can’t boot windows from USB Stick

Probably they didn’t find a way to ask you for registration and to collect your money every time they sense this USB is plug to other computer??

6. You cant see this on Windows:

# uptime
15:54PM up 122 days, 11:22, 5 users, load average: 0.12, 0.30, 0.13

every few days if you do not reboot windows machine it starts to act slowly due to the severe memory fragmentation