Software defined radio mesh network for active network management [Active SDR-MESH]

Short overview of a university project from some time ago.

The idea was to be able to measure the signal at various points, correlate with data from the GPS receiver and display the signal level; for a specific spectrum at a current location.

Continue reading “Software defined radio mesh network for active network management [Active SDR-MESH]”

Connecting to Azure via local PowerShell [Windows 10]

So to make life more interesting we will try to manage our Azure resources via PowerShell, running on our local workstation with Windows 10 Pro.

Before going to the details, its nice ot have updated help, which is done by typing:

To connect to Azure, there are some basics steps, before typing

There are some modulels that need to be installed and in order to do so, the appropriate policy should be set on your local instance:

After that, some modules must be installed

Wait some time, after which you could import the modules:

After that, connecting to Azure is as simple as typing:

Then you will be prompted to enter your Azure credentials on a form like this:

And in the end you should get something looking like this displayed on your PowerShell CLI:

You can also test by typing:

Which will dislplay all resouces, available within the current env.

Adding missing repositories for Debian

So, after installing Debian, if there is no network connection during installation, only the repositories available on the ISO will be added to the sources list. Hence, installing via simple apt command won’t be available.

Fortunately, the fix is quite straight forward and simple and it takes ~30 seconds :):

  1. Open terminal:

  1. Add the following lines:

  1. Run the update

  1. test with installing htop

  1. enjoy the easy life with linux :).

 

Connectivity overview for the lab

After some time spent installing, configuring, reading and rebooting, the lab is going quite well. Also, it might look like there are too many tools or too many solutions with overlapping capabilities, but its all in the name of lab testing :).

 

On the bellow diagram,  you could find the connectivity overview of the lab – inculind the on-premise secion and the two public clouds that will be integrated.

In future posts, there will be more info how to configure some of the components, for example the virtual router of MicroTik and so on.

Enable ping on windows 7/ Windows Firewall

By default, the pre-built windows firewall blocks ping requests. But ping being usually useful command, its convenient to be enabled, when working in a trusted environment.

 

To enable ping in Windows firewall:

  1. Open Start Menu
  2. Search for Windows Firewall
  3. Select Advanced Settings on the left
  4. Click Inbound Rules
  5. Find the rule, named: File and Printer sharing (Echo Request – ICMPv4)
  6. Right click on the rules and select “Enable”

Another option is to enable ping via GPO

Active directory interview questions, part 2 of 2

  • How does group policy resolve setting conflicts?
  1. Following the GPO’s processing order. More particular – the GPO containing the conflicting policy setting that applies last is the setting that overwrites all other settings.
  • Give three examples of where PowerShell pipeline should be used, rather than set as variable
  1. This is an intriguing question also in the Linux/bash environment.
  2. Allows data to be sent from one command to the second, without the need of variable definition
  3. Allows for easier ongoing refining of the function/script results
  4. Streaming/ piping values allow working with “infinite” length of continuous data, while its rather impossible to define such a variable
  • How do you establish a remote PowerShell session?  What are the pre-requisites?
  1. [If working within Domain] Enable PowerShell Remoting/ Enable-PSRemoting -Force
    1. Starts the WinRM service
    2. Starts automatically with system start
    3. Creates a firewall rule for incoming connection
  2. [If working within Workgroup]
    1. Configure the network as private
    2. Configure TrustedHosts on both machines.
  3. To execute a single remote cmdlet: Invoke-Command
  4. To initiate a remote session: Enter-PSSession

 

Where does ISO/IEC 27001 fits

ISO 27001 is a part of the bigger ISO/IEC 27000 family of standards – Information security management systems. The ISO/IEC 27000 family of standards assists commercial and governmental organizations in keeping their information assets secure.

Usage of the ISO 27000 family of standards helps the organization manage the security of various assets such as financial information, intellectual property, employee details or information entrusted to you by third parties.

ISO/IEC 27001 is the best-known standard in the family providing requirements for an information security management system (ISMS).

The last version of ISO 27001 is from few years ago – 2013m thus the naming convention of the current one is ISO/IEC 27001:2013.

It describes the best practices for information security management system and its purpose is to protect the confidentiality, integrity and availability of the information in a company. This is being addressed by discovering potential problems related to the information (i.e., risk assessment), and then defining what must be done in order to prevent those problems from happening.

Therefore, the main philosophy of ISO 27001 is based on managing risks: find out where the risks are, and then systematically treat them via applying proper control measures.

Active directory interview questions, part 1 of 2

Some questions from a recent interview for Active Directory specialist position:

 

  • What are some extended Active Directory attribute that are created when you install common enterprise Microsoft offerings?
    1. Depending on the MS product being deployed, there could be various changes on the schema. The good thing is that they are all well documented with sufficient description in Technet.
    2. For example, when installing Exchange 2016, attributes that are being created are: ms-Exch-UG-Event-Subscription-Link and ms-Exch-UG-Event-Subscription-BL.
    3. When deploying Skype for bussienss: msExchUserHoldPolicies, msRTCSIP-UserRoutingGroupId, msRTCSIP-MirrorBackEndServer
    4. etc.

 

  • Name 3 usage case of AD delegation that would be useful in a company
    1. Delegate Microsoft BitLocker Decryption rights to Help Desk
    2. Delegate new user creation and Identity and access management team [IAM]
    3. Delegate password reset to Global Service Desk users [GSD]

 

  • Solve for this scenario.
    o   User A needs access to
    §  \\company.share\Public
    §  \\company.share\Confidential
    §  \\company.share\Secret
    o   User B needs access to
    §  \\company.share\Public
    §  \\company.share\Confidential\Public
    §  Cannot have access to \\company.share\Confidential
    o   Solution needs to be scalable for the future


    1. Make 2 groups – User-a-category and User-b-category
    2. For the user-a-category, assign appropriate NTFS access to the specified folders in \\company.share\.
    3. For the user-b-category, assign NTFS access to the specified folders in \\company.share\.
    4. Set security permissions to the \\company.share\Confidential folder.

 

  • If a user calls and tells you a newly created distribution group is unable to accept email from clients.  What is the problem?:
    1. Analyze the error code, generated by sending emails [if available]
    2. Check if Group scope is appropriate  [Universe/Global/Domain local]
    3. Check if “Sender authentication” is enabled
    4. Check with Get-TransportServer | Get-MessageTrackingLog -sender “address of sender” -recipient “address of DL”
    5. Check if there isn’t an anti-spam filter interfering [althou this could be  depending if internal/external messages are being received]
    6. Remove the user from the group and add him again [some classical IT troubleshooting]

 

  • What is a loop back group policy?
    1. Allows user configuration settings to be applied, based on the computers GPO. Thus computers policies take precedence over user’s policies/ settings. Works in 2 modes:
    2. replace: the user policies defined in the computer’s GPO replace the user policies, normally applied to the user
    3. merge: the user policies defined in the computer’s GPO and the user policies normally applied on the user’s are merged. If a conflict occurs, the user policies in the computer’s default GPO overwrite the user’s normal policies.

Part 2 will be on soon.

 

Making remote server management easier

After making sure the networking is done, installation is complete, AD is created, DNS/ DHCP are proparly configured, time to make life easier by enabling remote server management.

On the managed servers, you need Remote server

  • On the computer that you want to manage remotely open a Windows PowerShell session with elevated user rights.
  • Type the following, and then press Enter to enable all required firewall rule exceptions.

    Configure-SMRemoting.exe -enable

On the management server

  • Navigate to server manager, in the upper right cornet select Manage and add Server
  • Fill the newly opened window with something like this:
Configure Remote Management in Server Manager
Configure Remote Management in Server Manager
  • Wait few seconds for the refreshment
  • Enjoy the improved functionality :).
Configure Remote Management in Server Manager
Configure Remote Management in Server Manager