Load balancing with 3 vms

Help
1

Hi there,

I want to load balance 3 IPs. I have followed the caddyfiles docs with example but I can get it. They have kinda telling things quite directly. Now the issue is, I dont know what file do I have to edit to make a load balancer.?

Secondly, Do I have to also install caddy on all the 3 Vms in order to make load balance.

I mean I dont basically know what step do I have to follow. Im completely noob. But have used Nginx a lot and also have done reverse proxy and load balancing using Nginx.

Ill highly appreciate if the answer is with steps.

Thank you

2

What you’re looking for is the proxy directive: https://caddyserver.com/docs/proxy

If you only need simple random load balancing, one of the examples does just that:

proxy / web1.local:80 web2.local:90 web3.local:100
1 Like
3

Ok thanks a lot for the reply.

Do you mean do I have to make changes into /etc/caddy/Caddyfile and what other lines do I have to enter despite proxy / web1.local:80 web2.local:90 web3.local:100.

Further, how can I test it.

4

The link in @1lann’s post to the http.proxy documentation is pretty comprehensive, particularly the examples section:

https://caddyserver.com/docs/proxy#examples

These go in your Caddyfile, with some adaptation to suit your backend hosts.

As for testing, I’d recommend checking the access logs of your backends - Caddy’s proxy will show up as standard client requests.

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5

Thank you for your reply, I have done everything and its working perfectly fine… But one of my setting is giving 502 bad gateway when i access via browser. But when I try other 3 ips it works perfect. Why do I experience a 502 bad gateway…

Below is the Caddyfile

#-----------------CASSANDRA

localhost:2021 {
        bind {$ADDRESS}

        proxy / http://10.0.0.242 http://10.0.0.243 http://10.0.0.244

        log /var/log/caddy/cassandra-demo_access.log

        errors log /var/log/caddy/cassandra-demo_error.log


 }


#-------------------KAFKA

localhost:2020 {
        bind {$ADDRESS}

        proxy / http://10.0.0.251 http://10.0.0.252 http://10.0.0.253

        log /var/log/caddy/kafka-demo_access.log {

    }
}

The Cassandra config works perfect for me but the Kafka section is giving 502 bad gateway… What can be the Issue

6

A 502 Bad Gateway from Caddy means that when you tried to connect to localhost:2020, Caddy tried to proxy your request to http://10.0.0.251 (or .252 or .253) but wasn’t able to establish a connection.

You’ll need to troubleshoot why those endpoints aren’t accepting HTTP connections. Start by using curl -i http://10.0.0.251 from your Caddy host, which will give you a good idea of exactly how that backend is (or isn’t?) responding to Caddy.

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