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Set shell variables from CLI output

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Now that you have the NIC ID, run az network nic show to get its information. You don't need a resource group here, since the resource group name is contained within the Azure resource ID.

az network nic show --ids $nicId

This command shows all of the information for the network interface of the VM. This data includes DNS settings, IP information, security settings, and the MAC address. The following query shows how to obtain the public IP address and subnet object IDs.

az network nic show --ids $nicId \
  --query '{IP:ipConfigurations[].publicIPAddress.id, Subnet:ipConfigurations[].subnet.id}' \
  -o json

{
  "IP": [
    "/subscriptions/.../resourceGroups/TutorialResources/providers/Microsoft.Network/publicIPAddresses/TutorialVM1PublicIP"
  ],
  "Subnet": [
    "/subscriptions/.../resourceGroups/TutorialResources/providers/Microsoft.Network/virtualNetworks/TutorialVM1VNET/subnets/TutorialVM1Subnet"
  ]
}

This command displays a JSON object that has custom keys ('IP' and 'Subnet') for the extracted values. While this style of output might not be useful for command-line tools, it helps with human readability and can be used with custom scripts.

In order to use command-line tools, change the command to remove the custom JSON keys and output as tsv. The read command processes this style of output by loading results into multiple variables. Since two values are displayed on separate lines, the read command delimiter must be set to the empty string rather than the default of non-newline whitespace.

read -d '' ipId subnetId <<< $(az network nic show \
  --ids $nicId \
  --query '[ipConfigurations[].publicIPAddress.id, ipConfigurations[].subnet.id]' \
  -o tsv)

If you don't want to use the Bash read or PowerShell -split command, you can set each variable separately.

$ipId = az network nic show --ids $nicId --query '[ipConfigurations[].publicIPAddress.id]' -o tsv
$subnetId = az network nic show --ids $nicId --query '[ipConfigurations[].subnet.id]' -o tsv

Use the public IP object ID to look up the public IP address and store it in a shell variable. The subnet ID was used to demonstrate how to query and store multiple values in the Azure CLI. Therefore, it isn't be needed for the rest of the tutorial.

vmIpAddress=$(az network public-ip show --ids $ipId \
  --query ipAddress \
  -o tsv)

Now you have the IP address of the VM stored in a shell variable. Go ahead and check that it's the same value that you used to initially connect to the VM.

echo $vmIpAddress