Hello Team,

I have noticed that this page did not mention the possibility of change the Vnet prefix via PowerShell.

Indeed, via Azure Portal does not allow it due to validation:

However, if you perform the same action via PowerShell, it allows you to change the same Vnet without any issue:

$virtualNetwork = Get-AzVirtualNetwork -ResourceGroupName testvnet -Name testvnet
$virtualNetwork.AddressSpace.AddressPrefixes.Remove("10.230.195.0/24")
True
$virtualNetwork.AddressSpace.AddressPrefixes.Add("10.230.195.0/26")
$virtualNetwork.AddressSpace.AddressPrefixes.Add("10.230.195.64/26")
Set-AzVirtualNetwork -VirtualNetwork $virtualNetwork

Documentation:
https://learn.microsoft.com/en-us/azure/virtual-network/virtual-network-manage-subnet
https://learn.microsoft.com/en-us/azure/virtual-network/manage-virtual-network

Thank you for reviewing.

Aline Dutra

Document Details

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• ID: b8332806-35c4-26e5-56e6-0286d728ad45
• Version Independent ID: ce76cee4-5629-7439-309c-9b9705891b57
• Content: Add, change, or delete an Azure virtual network subnet
• Content Source: articles/virtual-network/virtual-network-manage-subnet.md
• Service: virtual-network
• GitHub Login: @asudbring
• Microsoft Alias: allensu