If you're wondering what on earth this BOOTP and DHCP stuff is, more
information is available at
the DHCP WWW site. NFS is documented separately in detail
in the NFS HOWTO, and there's a DHCP mini-HOWTO too. I've tried to
provide enough details here to help you get started, whilst not
treating the topics in depth - let me know if you think this is
overkill.
In the BOOTP/DHCP + NFS configuration we're discussing, the KickStart
config file should be NFS mountable by the machine being installed
from /kickstart/IPADDR-kickstart on the BOOTP/DHCP server,
where IPADDR is the IP address of the new machine, e.g.
/kickstart/198.168.254.254-kickstart for the machine
198.168.254.254.
You should be able to override this location by returning
the bf parameter (boot file) in your BOOTP/DHCP response. It
may even be possible to have this NFS mounted off another machine
entirely.
To NFS export some directories from an existing Linux box, create the
file /etc/exports with contents something like:
Note that if you didn't register the IP addresses you're going to be
using in the DNS, you may be told to get lost by the NFS server and/or
the RPC portmapper. In this you can probably get away with putting
IP address/netmask pairs in the config files, e.g.
This is because most Linux distributions use TCP wrappers to do
access control for some or all of the NFS related daemons. Be aware
that the /etc/exports syntax tends to be different on other
Unix variants - the NFS servers bundled with Linux distributions
tend to offer a much wider range of options than the ones shipped
with other versions of Unix.
Be aware that if you include a root password in your KickStart config
file, or NFS export directories containing sensitive information, you
should take care to expose this information to as few people as
possible. This can be done by making the NFS export permissions as
fine grained as you can, e.g. by specifying a particular host or
subnet to export to rather than a whole domain. If you keep a special
IP address free for KickStart installations, everything's nice and
simple, but you'll have to change it later - or reconfigure the
machine to get its IP address via BOOTP/DHCP.
Most NFS servers require you to tell mountd and nfsd
(on some versions of Unix they're prefixed with a rpc.) that
the /etc/exports file has changed - usually by sending a
SIGHUP. There's often a program or script called
exportfs, which will do this for you, e.g.
# exportfs -a
If you didn't have NFS up and running when this machine was booted,
the directories may not be exported automatically. Try rebooting, or
running the following programs as root:
# portmap
# rpc.nfsd
# rpc.mountd
As noted, on some systems the rpc. prefix isn't used. In
most modern Unix distributions, these programs can be found in the
/usr/sbin or /usr/libexec directories. These might
not be in your path already, e.g. if you used su to become
root. The portmap program is also sometimes called
rpcbind, e.g. on Solaris, some versions of nfsd
require a command line argument specifying the number of instances of
the server to run, and you may find you also need to run another
daemon called biod. The above should suffice on most (all?)
Linux systems.
If you're using the CMU BOOTP server with DHCP and dynamic addressing
extensions referred to earlier, a sample /etc/bootptab entry
(/etc/bootptab is the normal location of the BOOTP/DHCP
configuration file) would look something like this:
This says to allocate IP addresses dynamically on encountering new
machines, starting at 198.168.254.128 and continuing for the
next 48 (the hexadecimal value 30) addresses. Each client
will be passed back the value of T250. In this case that
sets:
the DNS server ds to 198.168.254.2
the domain name dn to swedish-chef.org
the subnet mask sm to 255.255.255.0
the default gateway gw to 198.168.254.1
the lease length dl (how long the address is
valid for) to "forever"
There seem to be a number of other versions of this server kicking
around which do not support dynamic addressing. For these, you would
have to list the hardware (typically Ethernet MAC) address of each
to-be-installed machine in /etc/bootptab, and the entries
would look something like this:
