We have a internal load balancer deployed in Azure, with 4 VM currently in the same load balancer set. We have a software deployed as IaaS, they essentially running a windows service taking traffic from a pre-configured port (not 443)
I am trying to figure out how this will work, to my understanding, internal load balancer does not offload SSL, so my call will be end to end from client to the VM (could be any of the 4), I can configure the software to listen for a secure socket on same load balancer ports, but how should I configure my client to call 4 servers, which certificate to use in this case?
And, what if we have more VM adding to the picture?
Azure Load Balancer (including the Internal one) operates at the network layer, so it does not do SSL offloading or things like cookie-based affinity. If that's what you need, you may look into something like Azure Application Gateway or third-party layer 7 load balancers (Nginx Plus, Barracuda WAF, etc).
In your case, with the standard ILB, all requests will be routed to one of the 4 VMs, and all of them will need to have the SSL certificate installed (the same one in all VMs). SSL certificates, indeed, are bound to a specific hostname, but not a specific machine: if you need to load balance, you're free to re-use the same certificate (and private key) on every instance, as long as they all respond to the same hostname publicly.
Azure Load balancer does not provide SSL offloading. You could leverage KEMP LoadMaster-for-Azure and configure SSL offloading, by uploading certificate on the loadMaster and allow non ssl or SSL traffic to the 4 internal VMs. You could find the details in the below link
https://kemptechnologies.com/solutions/microsoft-load-balancing/loadmaster-azure/
Regards,
Krishna
Related
I have a pretty simple setup with an Application Gateway (AG), that sends traffic to a virtual machine running Ubuntu. The AG is loaded with an SSL certificate. The VM is set up to only allow incoming traffic from the AG, but it's an HTTP connection. This works, but I want to secure the traffic between my VM and AG. I can't find any relevant settings or documentation for this however.
How do I encrypt traffic between an Application Gateway and Virtual Machine? I considered a private link to at least force traffic over the Azure network, but private links only support PaaS products, where a VM is IaaS.
I assume your use the private IP of your VM in the backend settings of your Application Gateway. If so, this means that the traffic stays within your VNET and thus on the Microsoft network and also within the same region. You do not not need something like Private Link here.
So the only thing you could potentially do is to SSL-enable the endpoint on the VM and use an encrypted HTTPS connection between AppGW and your VM.
you have to do the same thing as with the api-gateway, load a certificate into de service deployed in the virtual machine and expose the API of this service using SSL protocol so the communication will be encrypted using that certificate.
The way to do it is different depending on which technology you are using to deploy your service. For example, if you are using spring-boot you can see how to do it here
https://www.baeldung.com/spring-boot-https-self-signed-certificate
However, you can use mutual-tls if you want that the only service that could connect to your VM's deployed service is the AG.
https://developers.cloudflare.com/access/service-auth/mtls
Disclaimers: I come from AWS background but relatively very new to GCP. I know there are a number of existing similar questions (e.g, here and here etc) but I still cannot get it work since the exact/detailed instructions are still missing. So please bear with me to ask this again.
My simple design:
Public HTTP/S Traffic (Ingress) >> GCP Load Balancer >> GCP Servers
GCP Load Balancer holds the SSL Cert. And then it uses Port 80 for downstream connections to the Servers. Therefore, LB to the Servers are just HTTP.
My question:
How do I prevent the incoming HTTP/S Public Traffic from reaching to the GCP Servers directly? Instead, only allow the Load Balancer (as well as it's Healthcheck Traffic)?
What I tried so far:
I went into Firewall Rules and removed the previously allowing rule of Ports 80/443 (Ingress Traffic) from 0.0.0.0/0. And then, added (allowed) the External IP address of Load Balancer.
At this point, I simply expected the Public Traffic should be rejected but the Load Balancer's. But in reality, both seemed to be rejected. Nothing reached the Servers anymore. The Load Balancer's External IP wasn't seemed to be recognised.
Later I also noticed the "Healthchecks" were also not recognised anymore. Therefore Healthchecks couldn't reach to Servers and then failed. Hence the Instances were dropped by Load Balancer.
Please also note that: I cannot pursue the approach of simply removing the External IPs on the Servers. (Although many people say this would work.) But we still want to maintain the direct SSH accesses to the Servers (by not using a Bastion Instance). Therefore I still need the External IPs, on each and every Web Servers.
Any clear (and kind) instructions will be very much appreciated. Thank you all.
You're able to setup HTTPS connectivity between your load balancer and your back-end servers while using HTTP(S) load balancer. To achieve this goal you should install HTTPS certificates on your back-end servers and configure web-servers to use them. If you decided to completely switch to HTTPS and disable HTTP on your back-end servers you should switch your health check from HTTP to HTTPS also.
To make health check working again after removing default firewall rule that allow connection from 0.0.0.0/0 to ports 80 and 443 you need to whitelist subnets 35.191.0.0/16 and 130.211.0.0/22 which are source IP ranges for health checks. You can find step by step instructions how to do it in the documentation. After that, access to your web servers still be restricted but your load balancer will be able to use health check and serve your customers.
I have 3 app servers running a NodeJS/ExpressJS app and a load balancer in front of them that routes the incoming requests (round robin). This setup is currently http based and we would like to have TLS certificate installed to make it https. Our devops guy has left the company and we have a huge gaping hole on understanding and maintaining this. I am pretty sure this setup does not have Apache or nginx in front of the app servers. So how does load balancing work without ngix or Apache? Does the load balancer have to run on a server by itself? if so is that where we need to install the TLS/SSL certificate ? All servers we use are linux based.
Generally, HTTPS termination happens on load balancer and normal HTTP connection is made between load balancer and server. By doing this, please ensure servers are not publicly exposed (not accessible from internet directly without load balancer).
Install the certificate on load balancer and configure it to make http request from loadbalancer to server. I am assuming you are using some IaaS (such as AWS, GCP etc) and these settings are readily available in their documentation.
Typically in AWS, either AWS Application Load Balancer is used for load balancing, which is a managed service provided by AWS where you will pay per hour and based on the traffic. Also, it is possible to terminate the TLS/SSL at Load Balancer Level (Where its also possible to use Free SSL Certificates from AWS Certificate Manager).
Since this Load Balancer is a managed service, the High Availability and Fault Tolerance is taken cared by AWS.
I've got multiple questions on the setup of a gateway and VM, so here is what I have actually.
I've got an Application Gateway, and two VM Ubuntu, everything hosted on Azure. They are all on the same Virtual Network. Both VM have only a private IP (10.1.0.4 and 10.1.0.5) and the Gateway have a private IP (10.1.1.4) and a public IP. Because only the Gateway have a public IP, I guess that everything have to go through it, and this is what I want to.
The goals I try to achieve :
Make a load balancer on the port 1680, redirected to port 1680.
To redirect the SSH of each VM to connect specifically to one because at the moment, they have no public IP. Is it possible to do this with a path based rule ? Like www.example.com/VM1 to connect by SSH to the first VM ? If no, what can be used to differentiate the SSH connection of the VM1 and of the VM2 ?
To redirect the port 80 of the gateway to the port 8080 of a specific VM. As my previous example, www.example.com/adminPanelVM1 to connect to the first VM on port 80 (redirected to port 8080 on the VM)
I already managed to create the redirection of the port 1680 of the Gateway with an HTTP Parameter, a Listener and a Rule.
Azure Application Gateway
The Azure Application Gateway operates at the layer 7 in the OSI model on the HTTP/HTTPS/WebSocket protocols, because of that any other protocol (like SSH), is not possible to route.
You got a few options tho.
You can use a Network Security Group, or NSG, for access control to your virtual machines. In the NSG you define where the traffic can come from that is allowed access to the VMs.
A NSG behaves like a access-control-list filtering traffic based on source and destination information and evaluating rules in order of priority. See this page for more information about NSGs.
Another option is to use a load balancer.
Azure Load Balancer
If you need to do port mapping, like you describe in your question, then a simple load balancer might be a better solution for you. An Azure Load Balancer works at a lower level in the in the OSI model, namely layer 4 (transport layer), handling TCP/UDP traffic.
So, if you are using a load balancer, then you can set up NAT rules to forward your traffic to specific machines, in other words, if you want to do:
LB port 1234 redirects to VM1 port 22 and
LB port 4312 redirects to VM2 port 22
you can do that using PowerShell as described in the Creating a public load balancer in Resource Manager by using PowerShell article.
There are quite a few steps but it walks you through the whole process of creating NAT rules, NICs and associated virtual machines.
Azure Application Gateway vs Azure Load Balancer?
These two cervices are distinctly different services and are trying to solve different problem, although those problems might look similar :)
The primary uses of an Application Gateway are:
SSL termination
cookie-based session affinity
round robin for load balancing traffic
Where as the Azure Load Balancer service works as the TCP/UDP level and support e.g. port mapping.
Cost wise, the load balancer service is free while the application gateway is billed per hour.
There are many great articles on this topic, when to pick which service. See for example the links for more details
When to use Azure Load Balancer or Application Gateway
Frequently asked questions for Application Gateway
I am new in Windows Azure, previously I have used Amazon Web Services.
In AWS you can set a SSL certificate for a Load Balancer and use it in listeners, so you don't need to worry about that in the web server.
Is it possible to set a SSL certificate for an Azure VM endpoint?
Azure Load Balancer is a layer 4 device, so it can't do SSL termination.
You can use Azure Application Gateway which is a Layer 7 Load Balancer, and it can do SSL termination. see here: https://learn.microsoft.com/en-us/azure/application-gateway/application-gateway-ssl-portal
EDIT: I am trying to understand if you are in "classic" VMs or not. Reading your the comments to your question, you ask if Azure VMs are in "Cloud Services" which implies you are in "classic", but it is unclear if you ask this because you have read the wrong doc, or this is the implementation you have. Anyway is it very recommended you get off "classic" and work with modern VMs. Especially for new deployments.
Loadbalancer comparation
AWS
Application Load Balancer - Layer 7 - HTTP, HTTPS
Network Load Balancer - layer 4 - TCP, UDP, TLS
Classic - Layer 4/7 - HTTP/HTTPS(layer 7), TCP, SSL/TLS(layer 4)
Azure
Load Balancer - Layer 4 - TCP and UDP
Application Gateway - Layer 7 - HTTP, HTTPS(support SSL)
Yes you can
Please check the documentation here:
http://azure.microsoft.com/en-us/documentation/articles/cloud-services-configure-ssl-certificate/
The Azure terminology is a little different from that of AWS. You can use the Azure Traffic Manager to offload TLS/SSL:
http://www.hanselman.com/blog/CloudPowerHowToScaleAzureWebsitesGloballyWithTrafficManager.aspx
(The Azure Load-Balanced Sets use round-robin DNS balancing, with VMs directly visible, whereas the Traffic Manager hides VMs behind the VIP)