Add a TCP rule to an existing Azure Load Balancer

add-azure-load-balancer-rule.ps1

#Make sure we are on the correct Azure Subscription
Get-AzContext

$lbName = "your-lb-name-here"
$rgName = "your-resource-group-name"
$probName = "the-lb-probe-name"
$bepName = "backend-pool"   ### the backend pool that has the VMs
$port = 10000               ### the port to load balance on the backend pool servers
$ruleName = "rule-name"     ###the name of the new rule

$slb = Get-AzLoadBalancer -Name $lbName -ResourceGroupName $rgName
$prb = Get-AzLoadBalancerProbeConfig -Name $probName -LoadBalancer $slb
$beaddpool = Get-AzLoadBalancerBackendAddressPoolConfig -Name $bepName -LoadBalancer $slb

# Add the rule to the configuration
$slb | Add-AzLoadBalancerRuleConfig -Name $ruleName `
  -FrontendIPConfiguration $slb.FrontendIpConfigurations[0] `
  -BackendAddressPool $beaddpool `
  -Protocol "Tcp" `
  -FrontendPort $port `
  -BackendPort $port ` 
  -Probe $prb

# Set the rule configuration
$slb | Set-AzLoadBalancerRuleConfig -Name $ruleName `
  -FrontendIPConfiguration $slb.FrontendIpConfigurations[0] `
  -BackendAddressPool $beaddpool `
  -Protocol "Tcp" `
  -FrontendPort $port `
  -BackendPort $port ` 
  -Probe $prb

# Note: you can add couples like the above Add/Set 
# so that your rules are added in one GO before
# touching the load balancer once with a single Set

#apply the changes to the load balancer
$slb | Set-AzLoadBalancer