global # The content of global is generally fixed and quite understandable.
        log 127.0.0.1   local2
        maxconn 4096
        user haproxy
        group haproxy
        chroot /var/lib/haproxy
        daemon
        pidfile /var/run/haproxy.pid
        stats socket /var/run/haproxy.sock         # Create a socket file for haproxy
        nbproc 40                                  # Start 40 processes to forward concurrently, higher versions can use nbthread, a threaded approach.

defaults # This section is mostly copied, not entirely clear on the options.
        log     global
        mode    http
        option  tcplog
        option  dontlognull
        retries 3
        option  redispatch
        maxconn 1024
        timeout connect 5000ms
        timeout client 50000ms
        timeout server 50000ms

listen cdb_cluster 0.0.0.0:3030  # The actual proxy name and address for receiving services.
## cdb balance leastconn - the cluster listening on port 3030.
        mode tcp
        balance leastconn  # This method is most suitable for databases; do not change.
        server cdb1 172.16.30.3:26257 check # Check seems to require a port for feedback status; without it, it might not work, but it doesn't matter.
        server cdb2 172.16.30.3:26258 check
        server cdb3 172.16.30.3:26259 check
        server cdb4 172.16.30.3:26260 check

default
# TCP keep-alive on client side. Server already enables them.
    option              clitcpka

listen psql
    option httpchk GET /health?ready=1