fix: Wait for management IP after creating ext network.

parts/k8s/windowskubeletfunc.ps1

@@ -405,8 +405,37 @@ if (!`$hnsNetwork)
 {
     Write-Host "Creating a new hns Network"
     ipmo `$global:HNSModule
+
+    `$na = @(Get-NetAdapter -Physical)
+    if (`$na.Count -eq 0)
+    {
+        throw "Failed to find any physical network adapters"
+    }
+
+    # If there is more than one adapter, use the first adapter.
+    `$managementIP = (Get-NetIPAddress -ifIndex `$na[0].ifIndex -AddressFamily IPv4).IPAddress
+    `$adapterName = `$na[0].Name
+    write-host "Using adapter `$adapterName with IP address `$managementIP"
+    `$mgmtIPAfterNetworkCreate
+
     # Fixme : use a smallest range possible, that will not collide with any pod space
-    New-HNSNetwork -Type `$global:NetworkMode -AddressPrefix "192.168.255.0/30" -Gateway "192.168.255.1" -Name `$global:ExternalNetwork -Verbose
+    New-HNSNetwork -Type `$global:NetworkMode -AddressPrefix "192.168.255.0/30" -Gateway "192.168.255.1" -AdapterName `$adapterName -Name `$global:ExternalNetwork -Verbose
+
+    # Wait for the switch to be created and the ip address to be assigned.
+    for (`$i=0;`$i -lt 60;`$i++)
+    {
+        `$mgmtIPAfterNetworkCreate = Get-NetIPAddress `$managementIP -ErrorAction SilentlyContinue
+        if (`$mgmtIPAfterNetworkCreate)
+        {
+            break
+        }
+        sleep -Milliseconds 1000
+    }
+
+    if (-not `$mgmtIPAfterNetworkCreate)
+    {
+        throw "Failed to find `$managementIP after creating `$global:ExternalNetwork network"
+    }
 }
 
 # Find if network created by CNI exists, if yes, remove it