I'm experiencing some deeply frustrating issues when trying to connect to a SQL server Private Endpoint. Setting aside for a moment a complete specification of the problem, I'd like answers to the following questions
Is it the case that a SQL Server Private Endpoint will only listen to connections from an Azure Virtual Machine? I have seen it suggested by 3rd parties that this is the case but cannot find this explicitly documented by MS. (To clarify, if only VMs can connect, then this would mean, for example, that an Azure Load Balancer could not use Private Endpoint as a backend resource; and, for example, that an on-premise VM could not connect to a Private Endpoint through a VPN - is that correct?)
Presuming the answer to the above question is Yes, then does the restriction apply such as to prevent Private Endpoint from listening to connections forwarded from an Azure VM interface?
(For example, say a firewall in a VM in Azure. Inside the firewall VM, the IP 192.168.0.10 is configured. In Azure, the VM interface is associated with only a single IP address which is IP 192.168.0.6. In this scenario, the firewall VM will respond to ARP requests with ARP responses saying "I have 192.168.0.10", but 192.168.0.10 is not associated by Azure configuration with any Azure virtual network interface. In said case, will a connection to the Private Endpoint using source address 192.168.0.10 work? Or is it the case that the PE will listen for connections only with a source address 192.168.0.6?)
To answer your questions:
It's possible that use a private endpoint as backends in the Azure Load balancer because Azure LB supports NIC or IP address as the backend target. Also, the on-premise VM surely can connect to a private endpoint through VPN tunneling, read this document for more details.
A VM by default sends all outbound traffic to the IP address that's assigned to the primary IP configuration of the primary network interface. So it will use source address 192.168.0.6 when connecting to the private endpoint. Read the network interface constraints.
Related
I have configured an Azure VPN point to site connection to access my azure resources prtected by VNet from my local machine. I was able to access all other resources except Azure Search Service using VPN. For all the resoucres I added the GatewaySubnet under "Selected Networks" of Networking settings and also mentioned the corresponding resource's IP address as additional route in VNet Gateway.
But for azure search service I cannot add the GatewaySubnet under selected networks because search service allows only public IP address range to be added when selecting "Selected Networks".
I am getting below error when connecting to search service with VPN connected
A connection attempt failed because the connected party did not
properly respond after a period of time, or established connection
failed because connected host has failed to respond.
System.Private.CoreLib: A connection attempt failed because the
connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.
Am I missing any setting? Can someone help me on this?
You don't need to add anything in the Azure Search Firewall, if you got "Selected Networks" as your firewall setting, it means that you have not yet created a private enpoint for Search, if your main goal is to connect privately from On premise to Search then this will be your first step.
https://learn.microsoft.com/en-us/azure/search/service-create-private-endpoint
After the private endpoint is created, make sure that your clients know how to resolve xxxx.search.windows.net to the private IP of the newly created private endpoint, once that's done, it would all be a matter of ensuring that the routing is setup correctly and your clients should then be able to connect.
At this time, the only way to access the search service privately is through private endpoint, as mentioned in this doc.
To create a private endpoint attached to the virtual network where the local machine VPN is part of. When you connect through VPN, the machine that you're connecting from would acquire a private IP from the virtual network.
-summarized the answer from comments.
I was missing setting up the DNS forwarder. The public addresses are returned by Azure public DNS. The private addresses are returned by DNS internal to Azure. This means that we want to use DNS internal to Azure when accessing resources over a VPN connection. And this internal DNS provided by Azure is outside of our VNet and so we have to explicitly forward that using our own DNS forwarder.
We must add a DNS server to the VNet if we want DNS support for P2S or S2S connections. We must stand up our own DNS Server, actually a forwarder, and add it to the VNG DNS server list. Azure does not provide any DNS server that is addressable from the VPN connection.
We used azure firewall as a DNS forwarder and now everything works with VPN connected.
I am trying to access resources that are secured behind private endpoint from a remote location using an Azure VPN Point-to-Site connection.
So far I have setup a conditional forwarder to send DNS requests to Azure's internal DNS IP address (168.63.129.16). With my setup I can resolve all my private endpoints using nslookup to their private IP addresses. I can also connect to services such as SQL server from my local machine (using SQL Server Management Studio in the case of SQL server).
The problem I am facing is that I can only access resources if I use a desktop client for a given service. If I try to do anything using the Azure Portal, I get an error stating that I cannot access resources using my Public IP address without adding it as an inbound IP address. Whilst this is certainly an option, I don't want to go down this road.
I am hoping there is an option where I can connect to private endpoint resources from Azure Portal whilst connected to my point-to-site VPN. Any ideas?
So far I have setup a conditional forwarder to send DNS requests toAzure's internal DNS IP address (168.63.129.16). With my setup I can resolve all my private endpoints using nslookup to their private IP addresses. I can also connect to services such as SQL server from my local machine (using SQL Server Management Studio in the case of SQL server.
AfAIK, the process which you are doing is correct, To fix this issue try to update the local host file on client desktop to deploy a recourse with private endpoint please refer this link for more in detail
By default when you create a Private Endpoint in the Azure Portal it will automatically lock out public access. Service Endpoints operate by adding routes to allow traffic out of the virtual network to reach the public endpoint of the service selected. If you are access resources error, update firewall rules to communicate with your Azure resources you really need to configure v-net traffic on the firewall settings
Next option is conditional forwarder, in your scenario the ble from every v-net, its public ip it won't overlap with any private ips, it available from inside of azure v-net unique to each
In conditional for forwarder, client asks the ip of a host like www.seraltos.com .The dns server looks to see the answer if knows, if not a lookup will done based on root servers or forwarder to find the ip address returns that to the client
For more information in detail, please refer below links:
Private Endpoints and DNS in Azure & Cannot access my own public IP
https://learn.microsoft.com/en-us/azure/storage/common/storage-private-endpoints
https://learn.microsoft.com/en-us/azure/private-link/manage-private-endpoint?tabs=manage-private-link-powershell
The Problem
I'm trying to understand more about networking, firewalls, and IP ranges to help me solve a few real-life problems. The problem I ran into is that the SQL server I'm connecting to has a firewall which can list individual IP's or IP ranges, but my ISP changes my IP fairly frequently, which means that whitelisting my current IP is a temporary solution and I'll eventually be disconnected.
The Question
If I wanted to stabilize my IP and make it so that it comes from a predetermined range (or even a single static IP), would the best way of doing that be to make a virtual network that I can VPN into that has a specified range of IP's? Or is there any easier solution?
Details
I'm interested in the answer at a broad level, but the specific database I'm connecting to is on Azure. Hence, my thought process would be to create a Virtual Network and and a Virtual Network Gateway, which I would connect to using a standard VPN connection tool like Hamachi or Open VPN. I'm assuming then that I could open up a tool like PGAdmin and connect to the database, because the database would consider the incoming connection to be from the IP range that I've whitelisted and that the Virtual Network sits on. Is this accurate?
As you stated, if there is a public IP range from your on-premise outbound traffic, you just need to whiltelist the IP list on the firewall of Azure SQL database server. It is a simple method.
If you want to block the public endpoint from on-premises machines, you can use private endpoint for Azure SQL database. Read On-premises connectivity over private peering for more details.
With Private Link, customers can enable cross-premises access to the
private endpoint using ExpressRoute, private peering, or VPN
tunneling. Customers can then disable all access via the public
endpoint and not use the IP-based firewall to allow any IP addresses.
I have a VMSS/svc fabric cluster on internal vnet (not public). The only inbound connections to the VMSS is from on prem through a Azure VPN Gateway.
How do I control the outbound IP address the VMSS go through when accessing the internet? In this case I do not want this traffic routed through a random IP address or through the VPN connection.
Basically I want to secure my Azure SQL so that the outbound internet IPs of the VMSS is whitelisted. And I don't want to add all Azure datacenter IPs.
You could look to use Forced Tunneling which would ensure that your control where the data egress occurs in your on-premises environment, however this would force any data in your Virtual Network back over your VPN connection which may not be desirable (or helpful if you don't control egress from there).
Failing this you could add a software-based firewall running on an Azure VM with a public IP onto the same VNet and then use User Defined Routes (UDRs) to force all traffic bound for the Internet to go via that and then use the public IP address in your SQL firewall.
Longer term you will be able to connect Azure SQL DB to VNets (or at least restrict access to it from one) - see the Uservoice site (and add your vote!)
I'd like to setup the below infrastructure in Azure. I have one possible solution, but it seems like it makes compromises in security architecture. Is there a better way to do this in Azure than in my compromised workaround?:
VM #1: Role: SQL Server and IIS. Server should have a unique public IP address. The hosted websites will be available through public port 80, and connect to local SQL Server.
VM #2: Role: IIS. Server should have a unique public IP address. The hosted websites will be available through public port 80, and will connect to SQL Server on VM #1.
This has been my experience so far:
No issues setting up VM #1.
With VM #2, I tried building it in the same cloud service as VM #1. When I did that, it was assigned the same public IP address as VM #1. Thus, in this scenario, hosting websites on port 80 on both machines doesn't work.
Next I tried building VM #2 in a different cloud service. This resulted in assignment of a unique public IP address. However, I was unable to obtain connectivity to SQL Server on VM #1.
Things I tried for the above: VM #1 SQL Server set as mixed mode, named SQL account provisioned (and connectivity confirmed locally), SQL configured to allow incoming remote TCP connections, firewall rule opened for incoming connections on TCP port that SQL runs under, but so far have not been able to connect to it from VM #2.
One architecture I believe would work is to open a public port on VM #1 and map that to the private SQL Server port. Then VM #2 could connect using the fully-qualifed public DNS name of VM #1. I believe Azure also would allow connectivity to be constrained to the public IP address of VM #2.
However, this seems less than ideal, because now SQL communication is being routed through a more public route than one would normally design for a data center, and an extra public port has to be opened on VM #1 (even if constrained by IP address, I'd rather not expose that surface area if not necessary). Additionally, sending the SQL Server data over a more public network hypothetically means transport security may need to be considered.
Research indicates connectivity between 2 VMs on different cloud services may not be possible using private ports, although the info I've found so far is not conclusive. So again, is there a better way to do this in Azure?
A single cloud service is a security boundary and the only way into it is through a public (input) endpoint on the unique public VIP of the service. A Virtual Network (VNET) can be used to host multiple cloud services and allow private visibility among them without going through a public endpoint.
A typical model would be to put an IIS website in a PaaS cloud service with a public VIP and the backend SQL Server in an IaaS cloud service with a public VIP but NO public endpoints declared on it. Both these cloud services would be hosted in the same VNET. This allows the front end web role instances access to the backend SQL Server instance over the private VNET. There is a hands-on lab in the Windows Azure Training Kit that describes precisely how to implement this.
In this case I would recommend separating the IIS/SQL Server combination so that the SQL Server box is in an IaaS cloud service with no public endpoint (although it will always have a public VIP). I would also recommend using either a Point-to-Site or Site-to-Site VPN which would allow you to access the VMs without exposing a public RDP endpoint. A point-to-site VPN is developer focused and very easy to configure. A site-to-site VPN is more of an IT thing since it requires configuration of a VPN router such as Cisco, Juniper or Windows Server.