The i386™ clients currently netboot from pointyhat; the other clients are self-hosted. In all cases they set themselves up at boot-time to prepare to build packages.
Although connected nodes are supported, disconnected cluster node support has been added. A disconnected node is one that does not mount the cluster master via NFS. It could be a remote node, for example. The cluster master rsync's the interesting data (ports and src trees, bindist tarballs, scripts, etc.) to disconnected nodes during the node-setup phase. Then, the disconnected portbuild directory is nullfs-mounted for chroot builds.
The ports-${arch} user can ssh(1) to the client nodes to monitor them. Use sudo and check the portbuild.hostname.conf for the user and access details.
The scripts/allgohans script can be used to run a command on all of the ${arch} clients.
The scripts/checkmachines script is used to monitor the load on all the nodes of the build cluster, and schedule which nodes build which ports. This script is not very robust, and has a tendency to die. It is best to start up this script on the build master (e.g. pointyhat) after boot time using a while(1) loop.
This, and other documents, can be downloaded from ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/.
For questions about FreeBSD, read the documentation before contacting <questions@FreeBSD.org>.
For questions about this documentation, e-mail <doc@FreeBSD.org>.