This directory contains the necessary pieces of node configuration overlays. A
runit core-service, 03-aa-overlays.sh, will look for a subdirectory (or at
least one file) in /etc/overlays with a name that matches the MAC address,
represented by ${macaddr}, of the machine. Each archive matching the glob
/etc/overlays/${macaddr}.* will be unpacked, if possible, by calling
tar -xf "${file}" -C /etc
to expand the contents into /etc on the running system. Any failure to expand
a file will print a warning but otherwise continue with the boot. Next, if a
directory /etc/overlays/${macaddr} exists, its contents will be copied into
the corresponding path in /etc.
Copy the core service to be executed by runit at boot:
cp 03-aa-overlays.sh /etc/runit/core-services
Make the overlay directory and copy the master configuration to it:
mkdir -p /etc/overlays
read -r _macaddr < /sys/class/net/eth0/address
cp -r master "/etc/overlays/${_macaddr}"
For every other client machine in the cluster, create a new subdirectory
/etc/overlays/${_cltmac}, where ${_cltmac} is the MAC address of the client
in the same format as /sys/class/net/eth0/address, and add custom
configuration overrides in those subdirectories. You should at least assign a
unique hostname to each client, unless your DHCP server will do so.
The file master/exports defines exports for specific clients in the
172.23.199.0/24 subnet. Adjust the addresses in this file to suit your
network and client node configuration. The exports expose paths /srv/nfs,
/srv/nfs/root and /srv/nfs/home; the root and home filesystems should be
bind-mounted at these locations. The master/rc.local override will perform
the necessary bind mounts.
The links in master/runit/runsvdir/default enable the dnsmasq server and
NFS server components necessary to serve boot files over TFTP and allow NFS
cients to mount common filesystems. Additional links can be made in
corresponding paths for any node overlay to enable services on a per-node
basis.
The file master/fstab defines a mount of the EFI system partition by UUID;
this UUID can be replaced with the value reported by
lsblk -n -o uuid ${esp_blkdev}
for a device node ${esp_blkdev} that refers to your specific EFI system
partition. However, it is probably best to disregard this sample fstab and
instead copy the file from the running system that forms the basis for the
master node.