The thing that makes casting so appealing for me is how ubiquitous it is. It eliminates situations with guests where they would recommend a show/movie only to find out that I can't easily play the content because it's only available on a streaming service that the guest pays for and I do not. As long as the guest brought a device and connected it to my WiFi, it more than likely could be casted without having to install another app and/or sign up for a new service (or have the guest login with their account).
I am becoming less optimistic about it though. I just do not think that the level of ubiquity that Chromecast reached even 10 years ago will be matched with a FOSS alternative. Developers would need to incorporate it into their apps, websites, etc. or it would need to be compatible with existing solutions. I doubt Google will open Chromecast up enough so other options can be fully compatible with it. Additionally, without the backing of a major corporation, I do not see developers taking the time to make their content compatible with another casting option.
Agreed! I am concerned though that even if a viable casting alternative started gaining momentum that Google would essentially prevent it from being widely adopted or incorporated into apps/websites the way that Chromecast is. I think it would have to be created by a large tech or media company and/or be compatible with Chromecast.
Apps are still really frustrating though. If an app exists (big if), I found the apps to either miss key features compared to the corresponding apps on other platforms or the UI/UX was terrible for a TV app.
I could get by if just one of casting or the apps were comparable to more popular alternatives. Having neither makes it very difficult to moved away from those alternatives.
I do not think what I would want as a replacement exists (yet). My main requirements are:
- Only FOSS software and firmware
- Similar level of "casting" compatibility/ubiquity as the discontinued Chromecast
- Easy navigation and/or great UI/UX
- Can be controlled with a stand alone remote control, phone/tablet/laptop, and remote services like Home Assistant
- As portable and low powered as the discontinued Chromecast (or no less portable than a small mini-pc)
- Ability to turn on/off the TV, switch inputs, and control the volume
- Ability to install apps/plugins to directly on the device (maybe even things like Lutris, Moonlight, or something similar for gaming)
- Ideally, the apps would be as well maintained and provide similar levels of quality as something like an Android TV or Apple TV
- (bonus) Ability to store media locally for offline playback
I think the closest I have seen is LibreELEC + Kodi on a RaspberryPi or mini-pc. It's still not quite there for my tastes though. Hopefully the recent Chromecast announcement will lead to more/better alternatives in the coming months!
I am comfortable routing traffic via domain name through a reverse proxy. I am doing that via Traefik and can setup rules so that different sub-domains, domains, and/or path is routed to the appropriate end point (IP address and port). The issue is that k3s does not receive that information for SSH traffic since SNI (ie: the sub-domain, domain, etc.) is not included in SSH traffic. If SSH traffic provided SNI information, this issue would be much less complicated as I would only need to make sure that the port 22 traffic intended for k3s did not get processed by SSH or any other service on the node.
If I were to setup a DMZ, I think I would need to setup one unique public IP per SSH service. So I would need to create a public DNS record for sftp.my.domain to VPS#1's public IP and ssh.forgejo.my.domain to VPS#2's public IP. Assuming both VPS#1 and VPS#2 have some means of accessing the internal network (eg: VPN) then I could port forward traffic received by VPS#1 on port 22 to 192.168.1.40:22 and traffic received by VPS#2 on port 22 to 192.168.1.50:22. I had not considered this and based on what I have seen so far, I think that this would be the only solution to allow external traffic to access these services using the normal port 22 when there is more than one service in k3s expecting traffic on port 22 (or any other port that receives traffic without SNI details).
Maybe I was not clear, but I do not think that you understand what I was trying to say with the second part of my last message.
Assume that multiple VIPs are setup and there is a load balancer IP for the SFTP entry point (eg: 192.168.1.40:22) and a different load balancer IP for the Forgejo SSH entry point (eg: 192.168.1.50:22). My local DNS can be setup so that sftp.my.domain points to 192.168.1.40 and ssh.forgejo.my.domain points to 192.168.1.50. When I make a request within my network, the DNS lookup will appropriately route sftp.my.domain:22 to 192.168.1.40:22 and ssh.forgejo.my.domain:22 to 192.168.1.50. I believe this is what you are recommending and exactly what I want. I will need to get the multiple VIP part of this setup worked out so I can do this.
However, this will not work when the traffic is received from outside of my network even if the above configuration is setup correctly. If you were to try to connect to either sftp.my.domain:22 or ssh.forgejo.my.domain:22, your traffic would be routed to my public IP address. My firewall/router would receive the traffic on port 22 and port forward the traffic to the single IP address assigned to that port forwarding rule. When k3s receives the traffic from my firewall/router, k3s will not have any SNI information (ie: it will not know whether you were using sftp.my.domain or ssh.forgejo.my.domain - or any other domain for that matter). Even if I were able to setup multiple port forwarding rules for port 22 on the firewall/router, I would still be unable to appropriately route the traffic because the firewall/router would also not know if the traffic was intended for sftp.my.domain or ssh.forgejo.my.domain. As a result, at most you would only be able to use one of the services because external traffic for both sftp.my.domain and ssh.forgejo.my.domain will be routed to the same IP address and k3s would have no idea what domain (if any) is being used.
There are a few solutions (eg: use different ports for each SSH or non-TLS trafficked service, wrap the SSH traffic in TLS to give k3s SNI information to route traffic to the appropriate endpoint, configure SSH on the node to route traffic to the appropriate IP address based on SSH user, require each client to use the local network or VPN, etc.), but none of them are as seamless and easy as routing TLS traffic which can use SNI information.
I had not thought about using IPv6 for this. It's definitely something that I would need to research more as I know that this would expose my attack surface and may require an overhaul of the network (or at least a very thorough review).
I'm not sure I understand the concern about Traefik. I am using it as a reverse proxy and forcing HTTPS for all applicable services (which unfortunately does not apply to this particular situation). I am honestly a little confused about the control plane, tls-san, gateway, load balancer, ingress, etc. and how they all work together. I may not be using Traefik as the Load Balancer and instead have Kube-VIP as the LoadBalancer. I did not configure Kube-VIP any particular way for Load Balancing, but I did configure Traefik with a few Load Balancer specific options. When I tried to setup Kube-VIP with the additional IP addresses for load balancing, I was unable to get k3s to work correctly so I assumed that Traefik was my Load Balancer instead of Kube-VIP.
That all makes sense and tried setting it up that way but could not get it to work. I am not sure if it was an issue with my network, k3s, Kube-VIP, or Traefik (or some combination of them). I will try getting it to work again.
Even if I do though, I would run into an issue if I publicly exposed these services (I understand there are security implications of doing so). How would I route traffic received externally/publicly on port 22 to more than one IP address? I think I would only be able to do this for local/internal traffic by managing the local DNS.
I'm already doing that, but just for one VIP. I think I just need to get the additional VIPs working.
I know that I will need to update my local network's DNS so that something like service#1 = git.ssh.local.domain and git.ssh.local.domain = 192.168.50.10 and service#2 = sftp.local.domain and sftp.local.domain = 192.168.50.20. I would setup 192.168.50.10 as the load balancer IP address to Forgejo's SSH entrypoint and 192.168.50.20 as the load balancer IP address to the SFTP's entrypoint. However, how would I handle requests/traffic received externally? The router/firewall would receive everything and can port forward port 22 to a single IP address, which would prevent one (or more) service from being used externally, correct?
It likely is a config issue, but likely not a config issue relating to SSH not using SSL/TLS (and therefor not using SNI). There is a lot of information out there about this exact issue, but very little about how to properly handle this issue.
- https://crypto.stackexchange.com/questions/60255/why-doesnt-ssh-use-tls
- https://community.traefik.io/t/routing-ssh-traffic-with-traefik-v2/717
- https://docs.gitea.com/installation/install-with-docker#ssh-container-passthrough
- https://security.stackexchange.com/questions/1599/what-is-the-difference-between-ssl-vs-ssh-which-is-more-secure
- https://stackoverflow.com/questions/67251200/does-ssh-use-sni-headers-and-how-sni-inject-to-ssh-tunnel-connection
- https://www.haproxy.com/blog/route-ssh-connections-with-haproxy
- https://serverfault.com/questions/34552/is-there-a-name-based-virtual-host-ssh-reverse-proxy/610971#610971
I am unsure if I understood everything correctly, but I believe I am already doing everything that you mentioned. I followed the Kube-VIP's ARP daemonset's documentation. The leader election works. I am not using Kube-VIP for load balancing though. Instead, I am using Traefik, which is using the same IP address that was assigned to the control plane during both k3s's and Kube-VIP's setup. However, I am unable to get any additional VIP addresses to properly route to Traefik.
Even if I did get the additional VIP addresses working, I think I still have one last issue to overcome. I can control the local network's DNS so that service#1 is assigned VIP#1 and service#2 assigned VIP#2. However, how would this be handled for traffic received externally? If the external/public DNS has service#1 and service#2 assigned to the network's public IP address, both service's traffic would be received by the router/firewall on port 22. The router/firewall could forward traffic on port 22 to (presumably) a single IP address, which would only allow service#1 or service#2 (but not both) to receive traffic publicly, correct?
I think I can avoid using metallb since I'm already using Kube-VIP.
I do not think that I am using Virtual IPs correctly as I tried setting it up, but it did not work. I assume the Virtual IP would just become the Load Balancer IP and I would need to configure Traefik and Kube-VIP (as well as my network) to use the Virtual IPs?
I guess I need to dig in a little deeper. I am currently only using Kube-VIP to provide a single IP address for the control plane. I think I may have it configured wrong though since that same IP address is the single load balancer IP used by Traefik.
I have struggled finding good documentation, hints, tutorials, etc. setting up Kube-VIP with Virtual IPs. Is there anything that you are aware of that might provide some assistant in setting that up correctly?
Thanks - I appreciate the response. However, for the services I'm asking about (eg: SSH, SFTP, etc.) do not support SSL/TLS and forcing SSL/TLS with a wrapper would likely cause incompatibility with clients.
I agree though - for other the services connecting via HTTP/HTTPS, there would likely either be some incompatibility or at least warning messages about not using SSL/TLS.
I am running a bare metal Kubernetes cluster on k3s with Kube-VIP and Traefik. This works great for services that use SSL/TLS as Server Name Indication (SNI) can be used to reverse proxy multiple services listening on the same port. Consequently, getting Traefik to route multiple web servers receiving traffic on ports 80 or 443 is not a problem at all. However, I am stuck trying to accomplish the same thing for services that just use TCP or UDP without SSL/TLS since SNI is not included in TCP or UDP traffic.
I tried to setup Forgejo where clients will expect to use commands like git clone git@my.forgejo.instance.... which would ultimately use SSH on port 22. Since SSH uses TCP and Traefik supports TCPRoutes, I should be able to route traffic to Forgejo's SSH entry point using port 22, but I ran into an issue where the SSH service on the node would receive/process all traffic received by the node instead of allowing Traefik to receive the traffic and route it. I believe that I should be able to change the port that the node's SSH service is listening on or restrict the IP address that the node's SSH service is listening on. This should allow Traefik to receive the traffic on port 22 and route that traffic to Forgejo's SSH entry point while also allowing me to SSH directly into the node.
However, even if I get that to work correctly, I will run into another issue when other services that typically run on port 22 are stood up. For example, I would not be able to have Traefik reverse proxy both Forgejo's SSH entry point and an SFTP's entry point on port 22 since Traefik would only be able to route all traffic on port 22 to just one service due to the lack of SNI details.
The only viable solution that I can find is to only run one service's entry point on port 22 and run each of the other services' entry points on various ports. For instance, Forgejo's SSH entry point could be port 22 and the SFTP's entry point could be port 2222 (mapped to the pod's port 22). This would require multiple additional ports be opened on the firewall and each client would need its configuration and/or commands modified to connect to the service's a non-standard port.
Another solution that I have seen is to use other services like stunnel to wrap traffic in TLS (similar to how HTTPS works), but I believe this will likely lead to even more problems than using multiple ports as every client would likely need to be compatible with those wrapper services.
Is there some other solution that I am missing? Is there something that I could do with Virtual IP addresses, multiple load balancer IP addresses, etc.? Maybe I could route traffic on Load_Balancer#1_IP_Address:22 to Forgejo's SSH entry point and Load_Balancer#2_IP_Address:22 to SFTP's entry point?
tl;dr: Is it possible to host multiple services that do not use SSL/TLS (ie: cannot use SNI) on the same port in a single Kubernetes cluster without using non-standard ports and port mapping?