Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!zaphod.mps.ohio-state.edu!rpi!uupsi!sunic!sics.se!obg From: obg@sics.se (Olof Backing) Newsgroups: comp.unix.ultrix Subject: Re: Reassigning IP-adress to boot clients Message-ID: <1990Aug8.064411.20690@sics.se> Date: 8 Aug 90 06:44:11 GMT References: <1990Aug7.111645.25785@diku.dk> Sender: news@sics.se Distribution: comp Organization: Swedish Institute of Computer Science, Kista Lines: 56 treese@crl.dec.com (Win Treese) writes: >In article <1990Aug7.111645.25785@diku.dk> harbo@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 . 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@crl.dec.com Digital Equipment Corp. WHOAMI: Olof Backing EMAIL: WHERE: Swedish Institute of Computer Science (SICS) obg@sics.se SNAIL: Professorsslingan 25/102, S-104 05 Stockholm, Sweden VOICE: + 46 8 166318