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Hello I am a student and new to networking. For a project I need to connect to a virtual machine and I am using Azure. Specifically Bastion because my Windows 10 Home does not have Remote Desktop. I created a free tier of a virtual machine and went to Bastion but it said the "To associate a virtual network with a Bastion, it must contain a subnet with name AzureBastionSubnet with prefix of at least /27." So I went to "manage subnet configuration" and tried to change the /24 to /27 but it said it said "failed to update" subnet is in use and can not be changed. Please help. Sorry if this is a newbie question.
Your VM is connected to a Virtual Network and a Subnet in this Virtual Network.
You need to create a new Subnet in the Virtual Network with the name AzureBastionSubnet and a subnet mask of /27 minimum. A /24 subnet is fine as well. The only requirement is the name AzureBastionSubnet.
For instance:
(If the reply was helpful please don't forget to upvote and/or accept as answer, thank you)
Regards
Andreas Baumgarten
Under the AzureBastionSubnet the name "default" is 10.1.1.0/24 and I was not able to connect to the virtual machine with Bastion which is why I posted this question. I assume I had to change the mask /24 to /27.
Could you please post your configuration of Virtual Network and Subnets (or screenshots).
This makes it easier to find a solution.
(If the reply was helpful please don't forget to upvote and/or accept as answer, thank you)
Regards
Andreas Baumgarten
Here you go let me know if you need more information for steps on what I need to do
https://i.imgur.com/uSypXka.png
https://i.imgur.com/1SyJsdM.png
The default subnet is 10.1.1.0/24. And the address space for the Virtual Network is 10.1.1.0/24.
This is why you can't add another subnet. But this is required for the Bastion Host.
(If the reply was helpful please don't forget to upvote and/or accept as answer, thank you)
Regards
Andreas Baumgarten
Here is the image of the address space
Hello @BMcInnis ,
Just checking in to see if @Andreas Baumgarten 's answer helped. If this answers your query, please don’t forget to click "Accept the answer" and Up-Vote for the same, which might be beneficial to other community members reading this thread. And, if you have any further query do let us know.
Hello @BMcInnis ,
Could you please provide an update on this post?
Kindly let us know if the below answers helped or you need further assistance on this issue.
----------------------------------------------------------------------------------------------------------------
Please don’t forget to close the thread by clicking "Accept the answer" wherever the information provided helps you, as this can be beneficial to other community members.
At the end it should look like this:
Virtual Network Address Space
Subnets
----------
(If the reply was helpful please don't forget to upvote and/or accept as answer, thank you)
Regards
Andreas Baumgarten
Based on your screenshots you can do the following:
Modify the address space of the vNet:
From 10.1.1.0/24
To: 10.1.0.0/16
After the address space of the vNet is increased you can add another subnet:
Name of the Subnet must be: AzureBastionSubnet
Subnet Address Space: 10.1.2.0/24
After this is done you should be able to deploy the Bastion Host using the now existing AzureBastionSubnet subnet
(If the reply was helpful please don't forget to upvote and/or accept as answer, thank you)
Regards
Andreas Baumgarten
Okay you are a wizard for getting me this far. Will make sure to give all the upvotes when this is over. I managed to create the Bastion. However one problem is I am failing to connect because
"The target machine is either unreachable or the username or password is incorrect"
when I made sure to write it down and the username is even showing up under SSH. So I guess I will try to just reset password and hopefully I get in. Thank you so far though and if you have any comments on that let me know, thanks.
Everything is working now?
If so, it would be great if you could mark the answer with "accept as answer". This will help others with their search for answers in Q&A.
Regards
Andreas Baumgarten
Oh yeah its working thanks.
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Fortunately, i googled my way into here and boom! @Andreas Baumgarten did answered the question. This is to confirm that your answers are correct and upvoted them to be Ok
