Disable AFD Backend Pool's Backend Host with Azure Cli or Azure REST API - azure

Question

Im trying to update an existing backend host of a AFD backend pool to have its status from Enabled to Disabled.
Is there a way to update existing backend host of Front Door backend pools?
currently, i can only see add, list and remove in the following azure front door cli docs:
az network front-door backend-pool backend add
az network front-door backend-pool backend list
az network front-door backend-pool backend remove
Is there one for update?
I've also looked into the Azure REST API docs and have not found an endpoint to update a backend host of AFD backend pools.

Answer 1

I am able to achieve your ask using PowerShell.
Here is the script:
$resourceGroup1 = "frontdoor"
$frontDoor1 = "msrini"
$afd = Get-AzFrontDoor -ResourceGroupName $resourceGroup1 -name $frontDoor1
$loadBalancingSetting1=$afd.LoadBalancingSettings
$afd.BackendPools.backends[0].EnabledState = "Disabled"
$backendpool1=$afd.BackendPools
$frontendEndpoint1 = $afd.FrontendEndpoints
$healthProbeSetting1= $afd.HealthProbeSettings
$routingrule1 = $afd.RoutingRules
$backendpoolsettings1 = $afd.BackendPoolsSetting
Set-AzFrontDoor -Name $frontDoor1 -ResourceGroupName $resourceGroup1 -RoutingRule $routingrule1 -BackendPool $backendpool1 -FrontendEndpoint $frontendEndpoint1 -LoadBalancingSetting $loadBalancingSetting1 -HealthProbeSetting $healthProbeSetting1 -BackendPoolsSetting $backendpoolsettings1

Answer 2

I was able to resolve my issue, the below script requires using azure cli with a logged in service principle.
Param(
[string]$desiredState, #"Enabled" or "Disabled"
[string]$frontDoorName,
[string]$resourceGroupName,
[string]$targetBackendPool,
[string]$targetBackendHost
)
# Get Access Token
$token = az account get-access-token | ConvertFrom-Json
$accessToken = $token.accessToken
$subscriptionId = $token.subscription
$tenantId = $token.tenant
$uri = "https://management.azure.com/subscriptions/$($subscriptionId)/resourceGroups/$($resourceGroupName)/providers/Microsoft.Network/frontDoors/$($frontDoorName)?api-version=2019-05-01"
$headers = #{ "Authorization" = "Bearer $accessToken" }
$contentType = "application/json"
# Get AFD Configuration.
Write-Host "Invoking Azure REST API to get AFD configuration"
$afdConfig = Invoke-WebRequest -method get -uri $uri -headers $headers | ConvertFrom-Json
# Edit AFD Configuration to toggle backend host state
Write-Host "Checking BackendHost: $targetBackendHost In Backend Pool: $targetBackendPool"
foreach ($backendPool in $afdConfig.properties.backendPools) {
if ($backendPool.name -eq $targetBackendPool) {
foreach ($backends in $backendPool.properties.backends) {
if ($backends.address -eq $targetBackendHost) {
$currentState = $backends.enabledState
Write-Host "Current State of $targetBackendHost is $currentState"
if ($currentState -eq $desiredState) {
Write-Host "$targetBackendHost is already in the desired state of $desiredState"
exit
}
$backends.enabledState = $desiredState
Write-Host "$targetBackendHost Updated to $desiredState."
}
}
}
}
$updateRequest = $afdConfig | ConvertTo-Json -Depth 100
# Update AFD Configuration.
Write-Host "Invoking Azure REST API to update AFD configuration"
Invoke-WebRequest -method put -uri $uri -headers $headers -ContentType $contentType -body $updateRequest
# Poll current state until the change has been fully propogated in azure
Write-Host "Polling AFD until update is complete."
do {
$afdConfig = Invoke-WebRequest -method get -uri $uri -headers $headers | ConvertFrom-Json
foreach ($backendPool in $afdConfig.properties.backendPools) {
if ($backendPool.name -eq $targetBackendPool) {
foreach ($backends in $backendPool.properties.backends) {
if ($backends.address -eq $targetBackendHost) {
$currentState = $backends.enabledState
}
}
}
}
Write-Host "$targetBackendHost is currently in $currentState"
Start-Sleep -Seconds 1
} until ($currentState -eq $desiredState)
Write-Host "$targetBackendHost has successfully been updated to $desiredState"

Answer 3

I did it using Powershell
$FrontDoor = Get-AzFrontDoor -ResourceGroupName "FrontDoorResourceGroupName" -Name "FrontDoorName"
$FrontDoor.BackendPools.Backends[0].EnabledState = "Disabled"
Set-AzFrontDoor -InputObject $FrontDoor