Internet address problem when booting diskless clients

[Michael Gengenbach]

We recently changed our internet addresses from the Sun standard class-C
192.9.200 to our new class-B-address 132.231. We decided to use the third
byte of the address to distinguish between the institutes and the fourth
byte to number the hosts.

After doing this, we had problems to automatically boot our diskless
client Suns. They're Sun 3/75 running SunOS4.0.1(Export). When the system
boots, it uses the DARPA Reverse Address Resolution Protocol to determine
it's address. It gets the address, recognizes the class-B- format and then
forgets the last 2 bytes. After that it tries to fill the 2 bytes from
it's EEPROM. But there you can store only one byte for the bootpath. So it
fills the third byte with all zero and adds the fourth from the EEPROM.
When you write the correct boot-command by hand, everything goes okay.

Now I can't believe that every Sun diskless client in a class-B-network
has the third byte all zero. So what can we do? Who can help?

Thank you.
   Michael