Cloud replica failover fails after upgrade to Veeam Backup & Replication 9.5 Update 4

Due to a newly introduced issue, the appliance configuration is not updated automatically during the upgrade.

The issue will be corrected in future releases. For current installations, all network extension appliances in VMware environments must be re-deployed, both on the tenant and SP sides:

For the tenant side, please refer to the following procedure: https://helpcenter.veeam.com/docs/backup/cloud/cloud_connect_tenant_appliance_redeploy.html?ver=95u4

For the SP side, either use the manual process: https://helpcenter.veeam.com/docs/backup/cloud/redeploy_appliance.html?ver=95u4
or leverage the PowerShell script below to automate mass deployment:

# Appliances of the following tenants will be skipped from redeploying.
# Make sure to include all tenants having active failover in order not to disrupt connectivity.
# Hint: Specify dummy non-existent tenant's name here to process all tenants.
$tenants_to_skip = "Tenant1", "Tenant2"
 
# Customizable suffix to be added to redeployed appliances. Must not be blank.
$suffix = "_new"
 
$skiptenants = Get-VBRCloudTenant -Name $tenants_to_skip
$skiptenantsID = $skiptenants.id
$appliances = Get-VBRCloudTenantNetworkAppliance | Where-Object {$_.Platform -eq "VMWare" -and $_.TenantId -notin $skiptenantsID}
ForEach ($appl in $appliances)
{
     $newName = $appl.Name + $suffix
     Write-Host "Updating" $newName
     Set-VBRCloudTenantNetworkAppliance -Appliance $appl -Name $newName -ErrorAction "Continue"
}