A new “ADSL” router in my virtual lab

I keep looking for ways to improve my virtual lab and made it as realistic as possible. Although using Mikrotik routers is enough to build a large infrastructure, it’s not completely accurate with the real world experience – Mikrotik routers always work.

In the real world, we often need to connect a Mikrotik router either directly to other types of devices or even behind an exotic grandma’s home appliance. On the other hand, this is the lab and I don’t need any fancy features in such software. I want to save every megabyte of RAM or disk space on my laptop.

My search was fruitful and I found the perfect candidate – FloppyFW. This is the fully functional Linux-based router/firewall that can fit on a single 1.44” floppy disk.

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Trojan on my Android tablet after the factory data reset

At the end of 2017 I decided to reset my Android tablet. I used it as an auxiliary on-field device. There was no important data on it, but it could do with a clear down, a fresh start. The factory reset is a very easy task on Android devices.

I ran the reset task, it restored my device to a clean state and everything looked fine. I spotted McAfee anti-virus on it and ran it just for fun. It updated itself, started the scanning process and alerted me of the threat. I had a Trojan virus on the factory reset device.

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Reading file details on the Windows Core system

If you want to view a file details in Windows with GUI, you need to right-click on the file in Explorer, select Properties from the context menu and then click on the Details tab. Easy.

Can you do the same task using only the command line? With a little magic and a few mighty tricks you can do that, too.

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Windows Update failed with the error code 8024402C

I have a very strict policy that servers must not access the Net. If a server needs to be accessible from the Net, it will be placed in the DMZ zone with very rigid firewall rules. To update all servers, I need to implement the WSUS server in the local network.

I never let servers update automatically. Rather, I let them notify me about available updates and then I will manually run an installation process.

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Reading system parameters using WMIC

A few months ago, I had a need to find the serial numbers on a few servers. This number is printed in small size letters either on a tag or sticker placed on the computer case. In most cases, that sticker isn’t visible without extracting the server from the rack. Too much hassle!

Luckily, virtually every brand name machine has its serial number inside the system’s BIOS. We just need access to that information. So, the information is there, but we can’t read it easily. The answer is to use WMI.

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Installation of IE11 failed with code 9C47

Recently, I found that one of the servers doesn’t have IE11. I was surprised by that, but OK. I never use IE (or any other browser) on any server. Additionally, most of the servers don’t even have the default gateway address.

I ran Windows update, it started to work….

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Weird Task Scheduler error 0x1

If you’re a “poor soul” administering an Exchange server, then you probably know that it lacks some of the security features. I use the smart host solution at the front of the server to increase email security. However, I will explain the concept of smart host in another article.

Part of this solution is the Spam Assassin anti-spam engine. The key problem here was the scheduled task that is used to update the Spam Assassin’s definition files; it failed with error 0x1 and the reason was weird.

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