DHCP


Sometimes you need to perform a network installation (i.e. when no USB or DVD drive is allowed to boot, but you can boot PXE). In case of FreeBSD you can use DNSMASQ to serve the DHCP that will assign the initial client address and configuration along with PXE boot image served over tFTP. At this point you will have bootloader running, so you can serve filesystem over NFS to obtain working environment and/or the installer..

  • Create a directory that will hold the target filesystem over network. In my case that was
    /usr/local/tftp/FreeBSD
  • Put OS/Installer files inside above directory
    cd /usr/local/tftp/FreeBSD
    wget http://(..)/file.iso
    7z x file.iso
  • Edit /etc/exports to export the filesystem over NFS
    /usr/local/tftp/FreeBSD -ro -alldirs -network 192.168.0.0
  • Install the dnsmasq
    pkg install dnsmasq
  • Setup the /usr/local/etc/dnsmasq.conf
    enable-tftp
    tftp-root=/usr/local/tftp/FreeBSD
    
    dhcp-range=192.168.0.50,192.168.0.60,255.255.255.0,1h
    dhcp-boot=boot/pxeboot
    dhcp-option=option:router,
    dhcp-option=option:root-path,/usr/local/tftp/FreeBSD
    
  • Restart services
    service nfsd onerestart
    service dnsmasq onerestart
  • In case you get bootloader running but troubles with NFS make sure that mountd is running. Also you can see who is using the NFS shares with
    showmount -a

PXE Boot always use initial DHCP/tFTP to fetch configuration and bootloader, so the first stage is similar and should work with other Operating Systems and Bootloaders as well, the rest is up to bootloader itself..

DHCP


My request for base DHCP Client options parsing was partially implemented.