Reassigning IP-adress to boot clients

[Olof Backing]

treese at crl.dec.com (Win Treese) writes:

>In article <1990Aug7.111645.25785 at diku.dk> harbo at diku.dk (Klaus Harbo) writes:

>   At our site we have several DEC3100s which all boot from a central server
>   (also a DEC3100). We have a central administration of our LAN, and they want
>   us to assign different IP-addresses to some our machines (all of them 
>   boot-clients).

>   Unfortunately it is unclear to me how this is done. Actually we don't even
>   know where the machine gets its own IP-address. I think I know that it gets
>   it through ARP from the boot server, but where does *it* get it? -- There
>   must be a file somewhere that contains information about which clients get 
>   which addresses. (Surely it can't be /etc/hosts ? -- I have tried that, and
>   doesn't seem to work).

>Unless you've made lots of local modifications, the easiest thing to do
>might be to simply delete and re-install the clients.

>Assuming that's not what you want to do, here's a method (assuming you
>boot with MOP):

>- shut down all the clients
>- update /etc/hosts, BIND, and YP as appropriate
>- make sure the server has its new address (usually obtained from /etc/hosts)
>- reboot the server
>- For each client, look in its etc directory on the server.  This is usually
>	a path of the form /dlclient0/hostname.root/etc.
>- There is a file there called netblk.c.  It is a data structure definition
>	defined in <sas/mop.h>.  You'll need to put the 32-bit integer
>	representation of the host address for the server in the second
>	field, the client address in the 4th field, and the new broadcast
>	address and netmask in the fifth and sixth fields.
>	(you can write a quick program to do the dotted-quad to number
>	conversion using the inet_addr() library routine.
>- When you're done editing, execute "cc -c netblk.c" to regenerate the .o
>	file, which is used in the boot sequence.
>- Boot the client.
>- Enjoy.

>I think I've covered everything here, but you should go through it carefully
>(and for one client to check it).  This is, of course, a completely
>*unsupported* procedure.  I've done this before, so it seems to work.

How 'bout using /etc/dms.new....

>Good luck, and happy hacking.

The same to you!
>Win Treese						Cambridge Research Lab
>treese at crl.dec.com					Digital Equipment Corp.

WHOAMI: Olof Backing                                  EMAIL:
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