How to netboot and install NetBSD/sparc

Preface

I've got a Sun SparcStation IPX which I want to install NetBSD on. This old machine has neither a cdrom nor an USB connector (USB was invented several years after these machines hit the market). You could hook up an external SCSI cdrom or a tape drive, but I have neither of them. Thus, netbooting the installer remains the only choice. The steps described below work out for NetBSD 8.0, 7.1.1, 6.0.1, 5.2, 4.0.1, and 3.1.1. My IPX has quite an old OpenBootProm or OBP, the "bios" of Sparc machines. OBP version 2.4 or older neither boots NetBSD 4.0.1, 5.2, 6.0.1, 7.1.1, nor 8.0 from disk due to an incompatibility with the second stage bootloader. In such case, you have to use the second stage bootloader from NetBSD 3.1.1. Netbooting these releases works fine, though..
The installer of NetBSD (sysinst) has an option to update an already installed system. This howto describes the steps which are neccessary to netboot the installer. Following these steps you should also be able to update your system.

Requirements

Either download NetBSD-8.0-sparc.iso or fetch all files separately:
- the network boot loader boot.net
- the install kernel netbsd-GENERIC.gz
- the install root filesystem rootfs.tgz
- everything from ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-8.0/sparc/binary/sets/
Download base.tgz from NetBSD 3.1.1
A network bootserver running
- a rarp server
- a tftp server
- a dhcp server
- a nfs server
- a kernel that supports nfs server.
At least the rarp and tftp servers must run on the same machine. The dhcp as well as the nfs server may each run on a different machine. For simplicity I installed everything on a single Gentoo Linux machine:
- rarpd is part of net-misc/iputils which might be already installed if you can execute tools like ping or ping6
- tftpd is also part of net-misc/iputils but requires (x)inetd. Therefore, I installed net-ftp/atftpd
- As dhcpd I used that one from ISC - net-misc/dhcp
- nfs requires a bunch of daemons. Just install net-fs/nfs-utils.
a free ip address for your Sparc box
a functioning network
your Sparc box, of course. Note that older Sparcs have a battery backed NVRAM. If that battery is dead, then the machine has no hostid and no mac address and won't boot. You can replace the original Mostek NVRAM with one from STM. Or you might attach a new battery. In any case, read the Sun NVRAM/hostid FAQ.

Screenshots

Here's my IPX running NetBSD 3.1.1, 7.1.1 and 8.0:

I recently replaced the old 426 MB SCSI harddrive (Seagate ST1480N) by a whopping 2 GB drive (ST32151N). Thus, I had enough disk space to install all sets.

You need a MAU transceiver in order to connect an IPX to a 10 MBit ethernet network. Serial console requires a custom built mini DIN 8 port to DB9 connector, which nowadays might go to a USB-to-serial dongle:

The pinouts for the serial console are documented in The Sun Hardware Reference Part 2 under the Miscellaneous Pinouts section.

Steps

If you downloaded the iso, mount it:

$ sudo mount -t iso9660 -o ro,loop /path/to/NetBSD-8.0-sparc.iso /mnt

Create a directory that will serve as tftp area:
```
$ sudo mkdir /tftpboot
```

Copy boot.net to /tftpboot/:

$ sudo cp -iv /mnt/sparc/installation/netboot/boot.net /tftpboot/

Check whether your Sparc box has a SUN4M or a SUN4C based architecture. For this, you might visit http://www.netbsd.org/ports/sparc/. For instance, an IPX is a SUN4C while a JavaStation is a SUN4M
Calculate the hexadecimal representation of your Sun's ip address, e.g. my IPX uses 192.168.0.22 which is C0A80016 in hex. You can use this command:
```
printf %02X%02X%02X%02X 192 168 0 22
```
In /tftpboot, create a symlink like this:
```
$ sudo ln -s boot.net C0A80016.SUN4C
```
Of course you should replace that hex ip address and architecture to match yours.
Put you Sparc's mac address along with its IP address to /etc/ethers:
```
08:00:20:c0:ff:ee	192.168.0.22
```
In /etc/conf.d/rarpd, set the interface rarpd should listen on, and let rarpd reply even if there's no boot image:
```
RARPD_IFACE="eth0"
RARPD_OPTS="-e -v -b /tftpboot"
```
Start rarpd:
```
$ sudo rc-service rarpd start
```
Start atftpd:
```
$ sudo rc-service atftp start
```

Edit /etc/dhcp/dhcpd.conf. At the bare minimum it should contain something like this:

subnet 192.168.0.0 netmask 255.255.255.0 {
  range 192.168.0.100 192.168.0.110;
}
host ipx {
  hardware ethernet 08:00:20:C0:FF:EE;
  fixed-address 192.168.0.22;
  next-server 192.168.0.10;
  option root-path "/data/netbsd";
}

Start dhcpd:
```
$ sudo rc-service dhcpd start
```
Create the directory that will serve as the netbooted kernel's root directory:
```
$ mkdir /data/netbsd
```

Copy netbsd-GENERIC.gz (the NetBSD kernel) to that directory:

$ cp /mnt/sparc/binary/kernel/netbsd-GENERIC.gz /data/netbsd/

Inside the root directory, copy netbsd-GENERIC.gz to netbsd so that the network bootloader will pick up the kernel:
```
$ cp -iv /data/netbsd/netbsd-GENERIC.gz /data/netbsd/netbsd
```

Extract the root filesystem (the --numeric-owner switch is important!):

$ tar -C /data/netbsd --numeric-owner -xvzpSf /mnt/sparc/installation/netboot/rootfs.tgz

Make the install sets available underneath the root directory:
```
$ cp -aiv /mnt/sparc/binary/sets /data/netbsd/
```

Export the root directory with NFS. Add to /etc/exports:

/data/netbsd	192.168.0.22(rw,no_root_squash,no_subtree_check)

Make sure NFS version 2 and UDP transport are enabled in /etc/nfs.conf:
```
[nfsd]
UDP=on
vers2=on
vers3=on
```
Optionally, make nfsd log to syslog by extending the variable OPTS_RPC_NFSD in /etc/conf.d/nfs:
```
OPTS_RPC_NFSD="-s -u 8"
```
Start NFS:
```
$ sudo rc-service nfs start
```

Extract the second stage bootloader from NetBSD 3.1.1:

$ tar -C /tmp -xzf /path/to/base.tgz ./usr/mdec/boot.388000

Connect a keyboard and a monitor to your Sparc box, or use a serial connection
After powering on, press Stop+A (Ctrl+A+F in minicom) to escape to the OBP prompt
At the prompt, type boot net. For very old OBPs, you might have to switch to the (N)ew command mode
When the kernel and sysinst have been loaded after several minutes (might take up to 30 minutes on very old machines), you can install NetBSD to disk
During the installation, choose Local directory as source media to install from. As base directory enter /, whereas the set directory should be /sets
After the installation, you have to install the second stage loader from NetBSD 3.1.1 if your OBP is on an old version. Thus, before rebooting the machine, select Utility menu, and then Run /bin/sh
Alternatively, reboot your Sun, let it try to load NetBSD, and if it fails with a Data Access Exception, your OBP is too old. In such case, you should be presented the OBP prompt again. If not, once again press Stop+A or Ctrl+A+F to enter the OBP. Then, type boot net to boot the installation system once again, but don't select (I)nstall/Upgrade. Instead, start a (S)hell
Mount the root disk you just installed NetBSD to, and chroot into it:
```
# mount /dev/sd0a /targetroot
# chroot /targetroot
```
Rename the current second stage loader (/usr/mdec/boot is hardlinked to /usr/mdec/boot.388000):
```
# cd /usr/mdec
# mv boot boot.80
# mv boot.388000 boot.388000.80
```

Grap the second stage loader from NetBSD 3.1.1 you extracted on your bootserver:

# scp user@bootserver:/tmp/usr/mdec/boot.388000 /usr/mdec/
# ln /usr/mdec/boot.388000 /usr/mdec/boot

Reinstall the bootloader chain:

# cp -v /usr/mdec/boot /
# installboot -v /dev/rsd0c /usr/mdec/bootxx /boot

Leave the chroot environment, unmount the local disk, and reboot NetBSD 8.0 from disk:
```
# exit
# umount /targetroot
# reboot
```

Generating the SSH host keys during first boot might take a long time (up to 2 hours) on such old machines, though.