I am using an Ingress using Google-managed SSL certs mostly similar to what is described here:
https://cloud.google.com/kubernetes-engine/docs/how-to/managed-certs#setting_up_a_google-managed_certificate
However my backend service is a grpc service that is using HTTP2. According to the same documentation if I am using HTTP2 my backend needs to be "configured with SSL".
This sounds like I need a separate set of certificates for my backend service to configure it with SSL.
Is there a way to use the same Google managed certs here as well?
What are my other options here? I am using, Google managed certs for the Ingress not to manage any certs on my own, if I then use self signed certificates for my service, that kind of defeats the purpose.
i don't think it's required to create SSL for the backend services if you are terminating the HTTPS at LB level. You can attach your certs to at LB level and the backed-end will be HTTPS > HTTP.
You might need to create SSL/TLS new cert in case there is diff version ssl-protocols: TLSv1.2 TLSv1.3, Cipher set in your ingress controller configmap which you are using Nginx ingress controller, Kong etc.
If you are looking for End to End HTTPS traffic definitely you need to create a cert for the backend service.
You can also create/manage the Managed certificate or Custom cert with Cert manager the K8s secret and mount to deployment which will be used further by the service, in that case, no need to manage or create the certs. Ingress will passthrough the HTTPS request to service directly.
In this case, it will be an end-to-end HTTPS setup.
Update :
Note: To ensure the load balancer can make a correct HTTP2 request to
your backend, your backend must be configured with SSL. For more
information on what types of certificates are accepted, see Encryption
from the load balancer to the backends ." end to end tls seems to be a
requirement for HTTP2
This is my site https://findmeip.com it's running on HTTP2 and terminating the SSL/TLS at the Nginx level only.
Definitely, it's good to go with the suggested practice so you can use the ESP option from the Google, setting GKE ingress + ESP + grpc stack.
https://cloud.google.com/endpoints/docs/openapi/specify-proxy-startup-options?hl=tr
If not want to use ESP check above suggested :
You can Mount Managed certificate to
deployment which will be used further by the service, in that case, no
need to manage or create the certs. In other words, cert-manager will create/manage/re-new SSL/TLS on behalf of you in K8s secret which will used by service.
Google Managed Certificates can only be used for the frontend portion of the load balancer (aka client to LB). If you need encryption from the LB to the backends you will have use self-signed certificates or some other way to store said certificates on GKE as secrets and configuring the Ingress to connect to the backend using these secrets.
Like this https://cloud.google.com/kubernetes-engine/docs/concepts/ingress-xlb#setting_up_https_tls_between_client_and_load_balancer
Related
I have Kubernetes with Kafka where is also running Istio with Strimzi. Certificates are stored in cert-manager. I want to use TLS passthrough in my ingress but I am a little bit confused of that.
When SIMPLE is used, there is credentialName, which must be the same as secret.
tls:
mode: SIMPLE
credentialName: httpbin-credential
It is nice and simple way. But how about mode: PASSTHROUGH when I have many hosts? I studied demo on istio web (https://istio.io/latest/docs/tasks/traffic-management/ingress/ingress-sni-passthrough/#deploy-an-nginx-server) and their certificate details are stored in server configuration file and they are creating configmap. In official Istio documentation is noted that this parameter is only for MUTUAL and SIMPLE.
What is correct and simple way to expose my hosts using istio ingress to external traffic using cert-manager?
The difference between SIMPLE & PASSTHROUGH is:
SIMPLE TLS instructs the gateway to pass the ingress traffic by terminating TLS.
PASSTHROUGH TLS instructs the gateway to pass the ingress traffic AS IS, without terminating TLS.
We have 10 different kubernetes pods which runs inside a private VPN, this pods are HTTP serving endpoints(not HTTPS). But this services would interact with HTTPS serving endpoints. Logically to make call to HTTP-S serving endpoints from a HTTP serving pod , the SSL server certificate trust is required. Hence we decided to store the SSL certificates inside each HTTP Service pods to make call to HTTPS serving pods.
I am wondering is there are any alternative approaches for managing SSL certificates across different pods in Kubernetes cluster? How about kubeadm for K8s certificate management ... any suggestions ?
This is more of a general SSL certificate question rather than specific to Kubernetes.
If the containers/pods providing the HTTPS endpoint already have their SSL correctly configured and the SSL certificate you are using was purchased/generated from a known, trusted CA (like letsencrypt or any one of the known, trusted certificate companies out there) then there is no reason your other container apps that are making connections to your HTTPS endpoint serving pods would need anything special stored in them.
The only exception to this is if you have your own private CA and you've generated certificates on that internally and are installing them in your HTTPS serving containers. (Or if you are generating self-signed certs). Your pods/containers connecting to the https endpoints would then need to know about the CA certificate. Here is a stackoverflow question/answer that deals with this scenario:
How do I add a CA root certificate inside a docker image?
Lastly, there are better patterns to manage SSL in containers and container schedulers like Kubernetes. It all depends on your design/architecture.
Some general ideas:
Terminate SSL at a load balancer before traffic hits your pods. The load balancer then handles the traffic from itself to the pods as HTTP, and your clients terminate SSL at the Load Balancer. (This doesn't really tackle your specific use case though)
Use something like Hashicorp Vault as an internal CA, and use automation around this product and Kubernetes to manage certificates automatically.
Use something like cert-manager by jetstack to manage SSL in your kubernetes environment automatically. It can connect to a multitude of 'providers' such as letsencrypt for free SSL. https://github.com/jetstack/cert-manager
Hope that helps.
My Kubernetes cluster has 2 applications.
A deployment connecting to an external API through https:// - lets call it Fetcher
A proxy service which terminates the HTTPs request to inspect the headers for rate limiting - called Proxy
The deployment uses the mentioned proxy, picture the following architecture
Fetcher deployment <-- private network / Kubernetes --> Proxy <-- Internet --> external API
Before I moved to Kubernetes this was solved by creating a self-signed certificate and certificate authority CA to trust and place them on the Fetcher and proxy. The certificate simply contained the IP address of docker as SAN.
X509v3 Subject Alternative Name:
DNS:example.com, DNS:www.example.com, DNS:mail.example.com, DNS:ftp.example.com, IP Address:192.168.99.100, IP Address:192.168.56.1, IP Address:192.168.2.75
However I can't do this in Kubernetes, can I? Since the IP addresses of both the deployment and service are not guaranteed, the IP's could change. I am using a Kubernetes CoreDNS solution, could I add the dns addresses in the certificate? I dont know enough about ssl/certificates to understand.
How can I create a certificate and CA in Kubernetes to create a trust between the certificate sent by the proxy with a custom certificate authority on the fetcher?
If you expose the proxy deployment via a service, then by default it will be assigned a ClusterIP which will be stable even as the IPs of the pods running the proxy may change over time. You will want to generate a cert with an IPSAN corresponding to the ClusterIP of the service, rather than any of the IPs of the pods. Check out the official docs regarding the "service" concept.
I am trying to setup Traefik on Kubernetes with Let's Encrypt enabled. I managed yesterday to retrieve the first SSL certificated from Let's Encrypt but am a little bit stuck on how to store the SSL certificates.
I am able to create a Volume to store the Traefik certificates but that would mean that I am limited to a single replica (when having multiple replicas am I unable to retrieve a certificate since the validation goes wrong most of the times due to that the volume is not shared).
I read that Traefik is able to use something like Consul but I am wondering if I have to setup/run a complete Consul cluster to just store the fetched certificates etc.?
You can store the certificate in a kubernetes secret and you reference to this secret in your ingress.
spec:
tls:
- secretName: testsecret
The secret has to be in same namespace the ingress is running in.
See also https://docs.traefik.io/user-guide/kubernetes/#add-a-tls-certificate-to-the-ingress
You can set up the ingress with controller and apply for the SSL certificate of let's encrypt.
You can use cluster issuer to manage the SSL certificates and store that tls certificate on ingress.you can also use different ingress controllers like nginx also can use service mess istio.
For more details you can check : https://docs.traefik.io/user-guide/kubernetes/
So I want to have this:
/ Nginx1 (SSL)
HAProxy-- Nginx2 (SSL)
\ Nginx3 (SSL)
But I have questions:
How do I update Letsencrypt certs on all nodes?
If I can't do this with certbot (+some config) - how do you do this? Maybe some distributed k/v storages?
The best thing is to use HTTP only services (not HTTPS) on Nginx nodes and configure SSL on balancer.
Options:
Traefik. Can be configured to auto update LetsEncrypt certs.
Fabio. Also can be configured to use SSL certs. (I've used Hashicorp Vault to store them). Need to configure updates myself.
Those 2 integrate well with service discovery tools like Consul.