How do I configure vpc to allow outbound traffic over customer gateway - networking

I have configured a vpc to communicate with an on-prem private network as outlined here I am able to ping servers in my on-prem network through the virtual gateway. I have two private subnets and my route table associated with each of those subnets is configured as below:
10.255.254.0/23 local
0.0.0.0/0 vgw-xxxxxxx
My expectation is that all of my traffic, internet or otherwise is being communicated over the vgw to the cgw and then be subject to our on-premise firewall policies. In fact the article linked above specifically says that is the case:
The instances in the VPN-only subnet can't reach the Internet directly; any Internet-bound traffic must first traverse the virtual private gateway to your network, where the traffic is then subject to your firewall and corporate security policies.
When running a server on one of the private subnets the output from traceroute looks like this:
My traceroute to www.google.com looks like this:
as you can see from above traffic to www.google.com is just dying on the first hop.
I know that this can be achieved by adding a NAT to the public subnet, but I would prefer that all traffic flow through the on prem network instead.
What piece am I missing to make this work?

Related

Unable to SSH/Ping to VMs on Private Network of Openstack/packstack

We are using a setup of Openstack-Train through a Packstack installation and Openvswitch as the backend of neutron.
We have created an external network (10.5.0.0/22), which is an internal network of our org. and an private network (10.3.0.0/22) linked via a router.
Our org. network is connected with a Pfsense firewall which has been given permission to connect the network 10.5.0.0/22 to 10.3.0.0/22 of openstack and vice versa.
In the security group of openstack, we have added the egress and ingress rule to allow traffic between the two networks.
However, we are unable to ping or SSH any VMs that are built on the private network (10.3.0.0/22) from our org. network (10.5.0.0/22).
VMs on the private network have internet connectivity and can ping google and ssh into our org. machines that are on the 10.5.0.0/22 ip range.
The only way to SSH into private network VMs seem to via a floating IP.
Is there a way to directly SSH into the private network VMs without using the floating IP?
Or is this part of openstack design?
Thank you
Do you have any physical network hardware like Switches that are configured to only allow a specific VLAN or subnet traffic?
Can you also share how your subnet is configured "openstack subnet show"
Security does isolate traffic outside a subnet so floating IP is alternative way in, but it's possible to have multiple ports on a vm with different subnets and access.

GCP - No Cloud NAT but given public IP leaves VPC

We have a VPC which has VMs with private IP addresses only. There is no Cloud NAT attached to this VPC, so we should not be able to reach out public IPs.
Despite of the aboves, we experienced that we were able to curl the following public IP address from an internal VM.
64.233.166.153
The subnet of the VM has Private Google Access enabled and there is a default route to the default internet gateway, no other route entry matches for this IP. But there is no Cloud NAT.
My questions:
How is it possible to reach public IPs without NAT at all?
Are there other reachable public IPs? (without Cloud NAT)
What are these IPs used for?
Looks like the IP address belongs to a GCP resource/API.
As per GCP documentation[1], when PGA(Private Google Access) is enabled GCP VM instances without external IP can connect to the set of external IP addresses used by Google APIs and services by enabling Private Google Access on the subnet used by the VM's network interface.
This could be the potential reason why your VM was able to speak with the Public IP.
[1] https://cloud.google.com/vpc/docs/configure-private-google-access
Answer provided by #dp nulletla is right.
#Robert - For your use case that you mentioned in the comments - to reach BQ API from GCE with private IP without leaving google backbone network, I believe VPC Private Service Connect (PSC) for Google APIs is the right solution approach for you.
By default, if you have an application that uses a Google service, such as Cloud Storage, your application connects to the default DNS name for that service, such as storage.googleapis.com. Even though the IP addresses for the default DNS names are publicly routable, traffic sent from Google Cloud resources remains within Google's network.
With Private Service Connect, you can create private endpoints using global internal IP addresses within your VPC network. You can assign DNS names to these internal IP addresses with meaningful names like storage-vialink1.p.googleapis.com and bigtable-adsteam.p.googleapis.com. These names and IP addresses are internal to your VPC network and any on-premises networks that are connected to it using Cloud VPN tunnels or VLAN attachments. You can control which traffic goes to which endpoint, and can demonstrate that traffic stays within Google Cloud.
Basically when you create PSC endpoint,you assign private IP address to this endpoint. You reach respective google API e.g. Big Query, you always connect via PSC endpoint IP. This way you can control egress traffic in your VPC firewall rule with deny all and allow only PSC endpoint IP.
Additionally you can go 1 step further and try to restrict traffic/data going to BQ APIs from your GCE/VPC on more granular level with the use of VPC Service Control. By setting the VPC SC perimeter you can define/enforce with more restrictive policies to avoid any sort of data exfiltration.
Thanks
BR
Omkar

Port forwarding with private IP

I use a static IP connection, Configured to TPLINK router.
I have a local server running which i can access from my network, but i want it to be accessed outside network.
So I did port forwarding. and its Successfully running.
Now the problem is :: The IP address of my WAN is also a private address like 10.10.X.X, so when am entering http://10.10.X.X, i can access my site, but not outside my network. Please guide me how to fix this?
If your WAN address is a private address, your ISP is using CGN. This is becoming more common since the RIRs have, or soon will, run out of public IP addresses to assign to ISPs. It sounds like your ISP has run out of public addresses and needs to use private addresses for its residential customers, reserving its remaining public addresses for its business customers which are willing to pay for public addresses.
Basically, your ISP is using NAT, too. You would need to have the ISP forward your port on its NAT router, but the odds of that are zero since it probably has a policy you agreed to to not host servers on your residential LAN (buried in the fine print of the ISP agreement). This situation will play out more and more over time.
You have to use the "Virtual Server" settings. Port triggering is used for.
Once the modem router is configured, the operation is as follows: 1. A local host makes an outgoing connection to an external host using a destination port number defined in the Trigger Port field. 2. The modem router records this connection, opens the incoming port or ports associated with this entry in the Port Triggering table, and associates them with the local host. 3. When necessary, the external host will be able to connect to the local host using one of the ports defined in the Incoming Ports field.
It is not used for incoming connections which are triggered from outside!
Of course, to have it working you have to have an application listening on that port not only having the firewall on Windows allowing the port.
After you set up the "Virtual Server" a port scanner should show you the port is open (even without having a running application listening) - it will try to port forward it. I use ShieldsUp for testing.

devstack juno networking route between networks

How can I configure neutron to allow routing between private networks in the same tenant? When I connect two private subnets with a router, I can't ping instances across the router.
The router isn't enough. You also need to specify a security group rule allowing incoming ICMP packets to the VMs.
It sounds like you need to set the host routes for each network or set the default gateway to be the router that connects the 2 networks.

Amazon AWS VPC Scenario 2: Specify the public IP address range of your network?

I am setting up a VPC on Amazon AWS using Scenario 2: VPC with Public and Private Subnets.
In the "Adding Rules to the WebServerSG Security Group" section, it specifies to set an inbound SSH rule, specifying allowed sources to be: "Your network's public IP address range".
I have an elastic IP address assigned to my NAT EC2 device. When I created my public web server (in the public subnet) I also assigned a public IP address to it (as part of the wizard). This does not appear in my elastic IP list for some reason (although I believe them to be the same thing right?). They are are not contiguous addresses.
I am not sure exactly what is supposed to happen here. Am I supposed to be able to ssh into the web server in the public subnet? Why would I specify that the only source to be able to ssh into the web server is my network's public IP address range? When I set the allowable source address to either of the public IPs, my connection is refused. Am I supposed to be SSH-ing somewhere else.
Could someone please explain to me exactly how this setup is supposed to work, in terms of how I am supposed to be SSH-ing into the instances remotely?
"Your network's public IP address range" means the network where you are -- not EC2... it refers to the public IP address or range of the computer where you're sitting now, your office network, your home network, any network where your traffic will be be coming from when you want to access the EC2 machines remotely to administer them.

Resources