F5 LTM pool member control for Powershell.ps1

F5 LTM pool member control for Powershell.ps1

[CmdletBinding()]

param(
    [string]$LTMName,
    [string]$Username,
    [string]$Password,
    [string]$ApplicationName,
    [string]$MemberIP,
    [int]$MaxDisableWaitTime,
    [int]$MaxOfflineWaitTime,
    [int]$MaxHealthMonitorWaitTime,
    [int]$ConnectionCountDisabled,
    [int]$ConnectionCountOffline,
    [ValidateSet('Enable','Disable')]
    [string]$EnableOrDisable
)

if ($OctopusParameters) {
if ($OctopusParameters['LTMName']) {[string]$LTMName = $OctopusParameters['LTMName']}
if ($OctopusParameters['Username']) { [string]$Username = $OctopusParameters['Username']}
if ($OctopusParameters['Password']) { [string]$Password = $OctopusParameters['Password']}
if ($OctopusParameters['ApplicatioName']) { [string]$ApplicationName = $OctopusParameters['ApplicationName']}
if ($OctopusParameters['MemberIP']) { [string]$MemberIP = $OctopusParameters['MemberIP']}
if ($OctopusParameters['MaxDisableWaitTime']) { [int]$MaxDisableWaitTime = $OctopusParameters['MaxDisableWaitTime']}
if ($OctopusParameters['MaxOfflineWaitTime']) { [int]$MaxOfflineWaitTime = $OctopusParameters['MaxOfflineWaitTime']}
if ($OctopusParameters['MaxHealthMonitorWaitTime']) { [string]$MaxHealthMonitorWaitTime = $OctopusParameters['MaxHealthMonitorWaitTime']}
if ($OctopusParameters['ConnectionCountDisabled']) { [int]$ConnectionCountDisabled = $OctopusParameters['ConnectionCountDisabled']}
if ($OctopusParameters['ConnectionCountOffline']) { [int]$ConnectionCountOffline = $OctopusParameters['ConnectionCountOffline']}
if ($OctopusParameters['EnableOrDisable']) { [string]$EnableOrDisable = $OctopusParameters['EnableOrDisable']}
}

function Wait-LTMPoolMemberConnectionCount() 
{ 
    param(
        [int]$MaxWaitTime = 300, #defaults to 5 minutes
        [int]$ConnectionCount = 0
    )
    

    [int]$serverside_curConns = 100;
    
    $elapsed = [System.Diagnostics.Stopwatch]::StartNew();

    while ( $serverside_curConns -gt $ConnectionCount -and $elapsed.ElapsedMilliseconds -lt ($MaxDisableWaitTime * 1000))
    {
        
        $serverside_curConns = ($poolMember|Get-PoolMemberStats|Select-Object -ExpandProperty serverside.curConns).value
        
        $remainingTimer = $MaxOfflineWaitTime - [int]($elapsed.ElapsedMilliseconds / 1000)
        Write-Output "Waiting for connections to drain to $ConnectionCount (currently $serverside_curConns) - $remainingTimer seconds remain"  
        Start-Sleep -s 5
    }
}

function Set-LTMPoolMemberOffline()
{
Write-Output "Disabling pool member $($poolMember.address)..."
        if (Disable-PoolMember -InputObject $poolMember) { Write-Output "Pool member $($poolMember.address) disabled!" ""; 
            Wait-LTMPoolMemberConnectionCount -MaxWaitTime $MaxDisableWaitTime -ConnectionCount $ConnectionCountDisabled }          
        
        Write-Output "Offlining pool member $($poolMember.address)..."
        if (Disable-PoolMember -InputObject $poolMember -Force) { Write-Output "Pool member $($poolMember.address) offline!" "";
            Wait-LTMPoolMemberConnectionCount -MaxWaitTime $MaxOfflineWaitTime -ConnectionCount $ConnectionCountOffline 
                } else { 
                    Write-Output "Error while disabling/offlining pool member $($poolMember.address)"; exit 1 }
}

function Wait-LTMPoolMemberHealthy() 
{ 
    param(
        [int]$MaxHealthMonitorWaitTime
    )
    

    $elapsed = [System.Diagnostics.Stopwatch]::StartNew();
    

    while (($availabilityState -ne "available"))
    {
        $remainingTimer = $MaxHealthMonitorWaitTime - [int]($elapsed.ElapsedMilliseconds / 1000)
        if ($remainingTimer -lt 1) { Write-Output "Timed out waiting for site startup!"; exit 1}

        $availabilityState = ($poolMember|Get-PoolMemberStats|Select-Object -ExpandProperty status.availabilityState).description
        if ($availabilityState -eq "available") { Write-Output "Site appears up!"; exit 0 } else { Write-Output "Waiting up to $remainingTimer more seconds..."; Start-Sleep -s 3 }
    }
}



$LTMpasswd = ConvertTo-SecureString $Password -AsPlainText -Force
$LTMcreds = New-Object System.Management.Automation.PSCredential ($Username, $LTMpasswd)

New-F5Session -LTMName $LTMName -LTMCredentials $LTMcreds -Default

Write-Output "App: $ApplicationName MemberIP: $MemberIP"

$poolMember = Get-PoolMember -Application $ApplicationName -Address $MemberIP
if ($poolMember.address -eq $null) { Write-Output "Error retrieving pool member $MemberIP in iApp $ApplicationName!"; exit 1 }

If ($EnableOrDisable -eq "Disable")
{
        Set-LTMPoolMemberOffline
}
elseif ($EnableOrDisable -eq "Enable") {          
        if (Enable-PoolMember -InputObject $poolMember) 
            { Write-Output "Pool member $MemberIP enabled, waiting for online status..."
              Wait-LTMPoolMemberHealthy  -MaxHealthMonitorWaitTime $MaxHealthMonitorWaitTime 
        } else { Write-Output "Enabling pool member $MemberIP failed!"; exit 1 }                
}