BMC load balancing control

Question

I installed k3s on one of the node on the TP2 and I am using NGINX as ingress controller Without any setup the ingress IP is automatically the same as the one of the BMC This is somehow amazing and unexpected The only drawback is that every time I want to make an HTTP request to the BMC this gets intercepted by nginx and end up with a not found error Is there any documentation on how to control the load balancer and what is actually load balancing Thank you very much Riccardo

inquisitor_1337 · Answer

Check metalLB

riccardopet · Answer

mmm no I am saying that wihtout any configuration NGINX uses the BMC address as the ingress instead of the address of one of the noes is this expected

_dhanos_ · Answer

I know nearly not enough about k3s and Kubernetes in general but this is not Nginx which uses an IP An app like this cannot just use an IP This IP had to be assigned to a node When setting IP addresses you always need to use these outside of the range of the DHCP in your router

werdnum · Answer

Yeah there is something funny going on with your configuration

werdnum · Answer

You presumably set the IP to the same as the BMC

werdnum · Answer

The IP of the node

werdnum · Answer

The default k3s LoadBalancer is Klipper which just listens to the relevant port on all nodes

werdnum · Answer

It s fairly common for DHCP to refuse to assign an IP address it s recently seen on ARP too

_dhanos_ · Answer

But then the BMC gets it s IP first it s network interface appears in the network first then the nodes with statically configured IPs

inquisitor_1337 · Answer

VladoPortos have a nice starting tutorial regarding networking https help turingpi com hc en us articles 8942935354013 Network setting

inquisitor_1337 · Answer

`Traefik is a pre installed component in the Kubernetes cluster` in k3s traefik as loadbalancer comes pre installed

riccardopet · Answer

I am using NGINX as a ingress controller Even in case I set somewhere by mistake that the IP of the ingress was the same as the one of the bmc the bmc the IP of the BMC was redirected to the NGINX controller This is why I was imagining that the BMC was somehow working as a loadbalancer for the nodes

werdnum · Answer

nope

werdnum · Answer

that shouldn t be happening

werdnum · Answer

I would check your node IPs and the BMC IP

riccardopet · Answer

Thank you I ll test it again installing everything from scratch

werdnum · Answer

Can you check the IPs

werdnum · Answer

I gotta know how this happened now

j0jux · Answer

if the OS on the BMC itself would understand IPVS it could do some cheap loadbalancing on layer 2 by MAC rewrite the mode is DirectRouting in IPVS In this case the Pis and the BMC need to be on the same L2 segment And only the SYN and ACK packets are seen by the BMC and the data is flowing via the switch directly to the client Nearly no work for the CPU of the BMC

j0jux · Answer

note some k8s CNIs use that too internally

j0jux · Answer

have a look at the documentation and used IP ranges of your loadbalancer and ingress controller to set non collliding IPs

riccardopet · Answer

The IP are assigned directly from the router using dhcp but they are static The IPs are 10 1 10 200 1 2 3 4 When you say non colliding you mean in different networks

riccardopet · Answer

ok that was my fault

riccardopet · Answer

I wrote an ansible playbook one year ago and in that playbook I set up metallb using the same address as the BMC to create a lb

riccardopet · Answer

so sorry to create this thread

j0jux · Answer

that what I meant the assignment vioa DHCP cannot be changed except for the DHCP server But the range MetalLB uses is declared in the config structures you write good that you found it

riccardopet · Answer

Yep I thought I was using metallb only for the kube api But nginx was there too

riccardopet · Answer

Thank you for your help anyway