DHCPD

For giving IP addresses to the clients with specific MAC addresses, dhcpd very common option.

Check here for more info: https://wiki.archlinux.org/title/dhcpd

Installation

With Alpine linux

# apk update
apk add dhcp

Configure it

vim /etc/dhcp/dhcpd.conf

With this config we give IP addresses to the clients with specific MAC addresses. Other clients will get IP addresses from the range.

We also setting the hostname for the clients.

option domain-name kube-cluster;
option domain-name-servers 10.10.10.1;
option subnet-mask 255.255.255.0;
option routers 10.10.10.1;
subnet 10.10.10.0 netmask 255.255.255.0 {
  range 10.10.10.100 10.10.10.250;
}

group {
  #next-server 10.10.10.1;
  #filename "boot.ipxe";

  option domain-name "cluster.kube-cluster";

  host master1.cluster{
    hardware ethernet ba:ba:00:00:11:01;
    fixed-address 10.10.10.51;
    option host-name "master1";
  }

  host master2.cluster{
    hardware ethernet ba:ba:00:00:11:02;
    fixed-address 10.10.10.52;
    option host-name "master2";
  }

  host master3.cluster{
    hardware ethernet ba:ba:00:00:11:03;
    fixed-address 10.10.10.53;
    option host-name "master3";
  }

  host node1.cluster{
    hardware ethernet ba:ba:00:00:12:01;
    fixed-address 10.10.10.71;
    option host-name "node1";
  }

  host node2.cluster{
    hardware ethernet ba:ba:00:00:12:02;
    fixed-address 10.10.10.72;
    option host-name "node2";
  }

  host node3.cluster{
    hardware ethernet ba:ba:00:00:12:03;
    fixed-address 10.10.10.73;
    option host-name "node3";
  }
}

Add interface to listen

vim /etc/conf.d/dhcpd
# DHCPD_IFACE="eth1"

Now enable and start the service

rc-update add dhcpd default
rc-service dhcpd start

When you change the config, you need to restart the service

rc-service dhcpd restart