## Last updated : Mon Sep 23 16:20:18 1996 When the bootpc code fails to find a suitable server or reply it prints a message like: > Unable to locate an IP address for this host. > ***Please report this problem** > > [Unable to continue] > The client then goes into a loop forwever sleeping. The reason for this is that carrying on is probably foolish so it waits for a human to interrupt it and sort out the problem. If you really know what you are doing then you can set --returniffail to cause it to return. Using bootpc like this you can tell if your machine is connected to the network. I use this for machines which are sometimes on the net, but get taken home by their users sometimes. If it fails try running --debug --verbose to see if this sheds any light on the problem. The reasons it can fail that I've encountered are: o No bootp server is serving this client on this network x Set one up. If you want to disable networking if there is no reply to bootp see the --returniffails option. There is support for this in rc.bootp now. o Your default network card doesn't get you to the local network, or is filtered or firewalled and not letting bootp packets through. x Try using --server IPaddress of the server, check the routes you have set allow all broadcast route to the local network. o You are using --server to point to a server which doesn't run a bootp server x Try not using it. o Packets from bootpc don't reach the server, watching the network they seem to go somewhere else. x You have a default route set up which doesn't reach the bootp server. E.g. testing bootpc on a live system with the default route pointing at your external router. The rc.bootp script sets up a simple default route to the local net. If you can't see the bootp server from this you need a router which understands the bootp gateway protocol. For testing, just set --server to point at your local subnet's broadcast address. e.g. I use 131.111.16.255. o You are using --hwaddr and the bootp server responds directly to the MAC address quoted not to the machine generating the request. x Try not using it. In modern bootp servers you can tell it to broadcast the replies or reply to a known other address, this can be helpful for debugging. o The server doesn't understand RFC1497 cookies (you get not all the information back and a "WARNING bp_xid mismatch" probably.) x Install a newer bootp server, or make do with the information you can get from the old one. If these don't seem to be the problem, use strace to trace the execution with --debug and --verbose and mail me the output, repeat also with --server IPaddress so I can try to see what went wrong. e-mail them to J.S.Peatfield@damtp.cam.ac.uk, I'll try to reply with suggestions or more questions pretty soon. -- Jon