Troubleshoot common software problems - Server Tutorial

- [Instructor] One of the most common areas of troubleshooting that we have to deal with on a daily basis, when it comes to troubleshooting our servers, is dealing with software related problems. So let's take a look at some of the common software problems that we find in our servers. First is something as simple as users not being able to log in. Now there's a number of reasons that a user won't be able to log onto their system. It usually ends up having to do with the user just forgetting their password, or just typing the wrong password too many times, which can also happen from something like a cap flock being on and they don't realize it and then their account may get locked out, but there can be other issues which have to do with the software configuration, user's password expiring, or maybe it changed without them knowing it. There's a whole slew of issues, but this is a very common problem that we have to deal with. Another common problem is users not being able to access a resource that they're looking for. So this could come down to most typically, I would say a permissions type issue where the permissions haven't been set up properly and therefore the user can't get access to the resource, but that's not always the case. Sometimes it can be maybe something more network related. Sometimes we have issues with memory leaks on the software that we have installed in our servers. And so the software has a flaw in its programming to where the memory or the RAM in the system is being all gobbled up by the one application and then eventually the system locks up. And speaking of a system locking up, we have the dreaded blue screen of death, or what's also known as a stop screen, and this is a very common thing that we have to deal with. There's all sorts of reasons that we can have a stop screen or a blue screen of death, and if you get really good at it, you can actually read some of the code that's on the blue screen of death that will help share with you what has caused this. Now this could be because of a hardware problem, and very often people think it is because of a hardware problem that you're getting one of these stop screens, but more often than not, it's actually software, typically driver related issues. So while it looks like hardware, it's actually the software driver. And then we have operating system boot failures, where we attempt to just boot up the system and we can't get into the operating system the way we expect to. This can happen from either the result of either some form of driver input/output related failure, or it could be from some kind of corrupt files that are related to booting up the operating system. Now, I mentioned a moment ago with the blue screen of death that very often it is caused because of drivers, okay? So drivers are little pieces of software that tell the operating system how to communicate with your hardware components. Very often, if these drivers are either out of date, or even we can have the opposite problem where maybe they get updated, but with a corrupted version of the driver or an incompatible version of the driver, well, that may cause a problem. And we can also have what's called a runaway process, right? So I talked to you about the memory leak, right, where you can have an application, which is sucking up all the memory. Well, you can also have an issue where an application is tying up the processor and it can be done so in a way that it won't let anything else have access to the processor, and if you were to take a look in the Task Manager, for instance, in Windows, you can actually set priorities to your different applications, and if you end up with an application that has a higher priority, which means it gets first dibs at the processor, and then that application actually has a problem that's using up the entire processor, everything else can get locked up, including the operating system itself, to where you can't even kill the runaway process. Another problem that we run into sometimes is the inability to mount one of our drives that we need to be able to connect to. This is an isolated scenario where we suddenly can't write to the system log, which is very important to the maintenance of your system. And usually this has to do with the log running out of space and not being configured to be able to overwrite older log items with newer ones. And then we have just overall slow operating system performance. Now the cause of slow operating system performance can be a whole variety of things ranging from a hardware problem that's actually leading to the slow operating system performance, or you could have some form of rewrite issue that's causing the operating system performance issue, or it could be many of the other things we've already mentioned as far as a memory leak or runaway process, things like that. So there's a lot of things to look at when it comes to bad operating system performance. Continuing on, we have patch update failures. So our operating system, and our applications for that matter, very often are patched with updates. Some of the most important updates have to do with security related updates, and sometimes we have a failure when attempting to install those updates. Now, sometimes that failure is just something as simple as a network issue and you can try again and everything will be fine, and sometimes I'll even go in a different direction and say that sometimes it's the patch itself that causes the failure. Sometimes a patch has put out and it hasn't been as thoroughly tested as we hope and then that patch actually gets installed successfully, but that causes a failure in your system. We also have service failures. Sometimes you'll see that a system service is supposed to be running, but it'll show that it is stopped. Now I will tell you in today's modern Windows operating systems, very often when you first boot up the computer, you will find service failures and it's really unavoidable. And it's because they have what's called a delayed start. You want to go ahead and make sure you pay attention to those and know when it's a delayed start issue versus a service that's failing that otherwise needs to be running. Another problem, I would say it's not necessarily as common as some of the errors is when a system will hang when trying to do a proper shutdown, right? You're trying to do a proper shutdown and the only way you can turn off the system is by pressing and holding the power button to physically turn off the computer as opposed to letting it do a proper shutdown. So you want to try to avoid that when you can, sometimes it's unavoidable. And even beyond that, to solve this, basically you'll have to be familiar with going in and hacking some of the registry settings sometimes to get around that. And then we have issues with users not being able to print. This happens, whether it be a printer that is attached locally or even more so when you have a printer that is connected via the network, especially through the server, So what are some of the causes of these problems? Well, one cause is something called User Account Control. This is a Windows feature and it's really a security feature to help keep the system secure. Well, very often those security features will end up getting in the way of just regular, everyday necessary activity. So you want to pay attention to that. Sometimes you'll have files that are corrupted, you could be running out of hard drive space, or maybe running out of system resources, short on memory, too weak of a processor, maybe you need more processing threads, things like that. You could also have virtual memory issues where it's the virtual memory, which is a section of the hard drive that you reserve as an additional RAM. So that's why we're saying it's virtual though, it's not actual RAM, it's part of a hard drive. Well, it could be a configuration issue or a corruption issue. You can have fragmentation on the hard drive where files are all over the place and so you end up with major performance issues. And when it comes to printing, you could have actual print server drivers and services issues that are causing the problems, or could be the print spooler itself, which is where print jobs are held until they're ready to go to a print device. Now, what are some of the tools that we have available to help us solve some of these software problems? Well, we have our system logs, right? I mentioned just a few minutes ago about how one of the common problems is that we can't write to the system log. Well, the reason that's such a big problem is because the system logs is one of the best tools that we have to help solve problems. Another set of tools we have are a variety of monitoring tools. In Windows, we have performance monitor or resource monitor, or even there's a monitoring tool built right into the Task Manager. And so being able to monitor what's happening is very important. We have defragmentation tools which will help get the hard drive back in shape if it gets fragmented. And speaking of the hard drive, we have overall disc property tools, which help us to manipulate usage and if there's any free space, create volumes and drive mappings, okay? So we have tools that can help us to go ahead and create different types of drive volumes, different sizes, expanding or contracting the drives, things like that. So these are some of the tools that we also have at our disposal. But overall, this is just a high-level list of some of the software issues that typically deal with, with our servers. In no way, shape or form, all encompassing. There's all sorts of issues and unheard of issues that you may come across, but it's important to have a general idea of the software issues you have and the tools and resources you have at your disposal.