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diff --git a/contrib/isc-dhcp/README b/contrib/isc-dhcp/README new file mode 100644 index 0000000000000..c0f45ed9010ae --- /dev/null +++ b/contrib/isc-dhcp/README @@ -0,0 +1,236 @@ + Internet Software Consortium + Dynamic Host Configuration Protocol Distribution + Version 2, Beta 1, Patchlevel 0 + December 6, 1997 + +This is the first Beta release of Version 2 of the Internet Software +Consortium DHCP Distribution. In version 2.0, this distribution +includes a DHCP server, a DHCP client, and a BOOTP/DHCP relay agent. +This beta is believed to be fairly stable. However, DHCP server users +running a production environment should probably still use version +1.0, which is more stable, having been in a feature freeze since +November of 1996. + +In this release, the server and relay agent currently work well on +Digital Alpha OSF/1, SunOS 4.1.4, NetBSD, FreeBSD, BSD/OS and Ultrix. +They can also be run usefully on Solaris as long as only one broadcast +network interface is configured. They also runs on QNX and Linux as +long as only one broadcast network interface is configured and a host +route is added from that interface to the 255.255.255.255 broadcast +address. If you are running a Linux 2.0.31 kernel, the DHCP daemons +may be able to operate on more than one interface. + +The DHCP client currently only knows how to configure the network on +NetBSD, FreeBSD, BSD/os, Linux, Solaris and NextStep. The client +depends on a system-dependent shell script to do network +configuration - support for other operating systems is simply a matter +of porting this shell script to the new platform. + +If you wish to run the DHCP Distribution on Linux, please see the +Linux-specific notes later in this document. If you wish to run on a +SCO release, please see the SCO-specific notes later in this document. +You particularly need to read these notes if you intend to support +Windows 95 clients. If you are running a version of FreeBSD prior to +2.2, please read the note on FreeBSD. If you are running HP-UX or +Ultrix, please read the notes for those operating systems below. +If you are running NeXTSTEP, please see the notes on NeXTSTEP below. + +If you start dhcpd and get a message, "no free bpf", that means you +need to configure the Berkeley Packet Filter into your operating +system kernel. On NetBSD, FreeBSD and BSD/os, type ``man bpf'' for +information. On Digital Unix, type ``man pfilt''. + + + BUILDING THE DHCP DISTRIBUTION + +To build the DHCP Distribution, type ``configure''. If configure can +figure out what sort of system you're running on, it will create a +custom Makefile for you for that system; otherwise, it will complain. +If it can't figure out what system you are using, that system is not +supported - you are on your own. + +Once you've run configure, just type ``make'', and after a while you +should have a dhcp server. If you get compile errors on one of the +supported systems mentioned earlier, please let us know. If you get +errors on a system not mentioned above, you will need to do some +programming or debugging on your own to get the DHCP Distribution working. + + LINUX + +There are three big LINUX issues: the all-ones broadcast address, +Linux 2.1 ip_bootp_agent enabling, and operations with more than one +network interface. + + BROADCAST + +In order for dhcpd to work correctly with picky DHCP clients (e.g., +Windows 95), it must be able to send packets with an IP destination +address of 255.255.255.255. Unfortunately, Linux insists on changing +255.255.255.255 into the local subnet broadcast address (here, that's +192.5.5.223). This results in a DHCP protocol violation, and while +many DHCP clients don't notice the problem, some (e.g., all Microsoft +DHCP clients) do. Clients that have this problem will appear not to +see DHCPOFFER messages from the server. + +It is possible to work around this problem on some versions of Linux +by creating a host route from your network interface address to +255.255.255.255. The command you need to use to do this on Linux +varies from version to version. The easiest version is: + + route add -host 255.255.255.255 dev eth0 + +On some older Linux systems, you will get an error if you try to do +this. On those systems, try adding the following entry to your +/etc/hosts file: + +255.255.255.255 all-ones + +Then, try: + + route add -host all-ones dev eth0 + +Another route that has worked for some users is: + + route add -net 255.255.255.0 dev eth0 + +If you are not using eth0 as your network interface, you should +specify the network interface you *are* using in your route command. + + IP BOOTP AGENT + +Some versions of the Linux 2.1 kernel apparently prevent dhcpd from +working unless you enable it by doing the following: + + echo 1 >/proc/sys/net/ipv4/ip_bootp_agent + + + MULTIPLE INTERFACES + +Most older versions of the Linux kernel do not provide a networking +API that allows dhcpd to operate correctly if the system has more than +one broadcast network interface. However, Linux 2.0 kernels with +version numbers greater than or equal to 2.0.31 add an API feature: +the SO_BINDTODEVICE socket option. If SO_BINDTODEVICE is present, it +is possible for dhcpd to operate on Linux with more than one network +interface. In order to take advantage of this, you must be running a +2.0.31 or greater kernel, and you must have 2.0.31 system headers +installed *before* you build dhcpd. + +NOTE: People have been having problems finding the 2.0.31 kernel +because it was only available as a prerelease patch. As of October +17, Linux 2.0.31 is the stable Linux kernel, and is available as a +kernel distribution rather than as a test patch. With any luck, it +will be in the latest version of your favourite Linux distribution +soon. + +If you are running a Linux 2.1 kernel, this does not guarantee that you +have SO_BINDTODEVICE. Linux 2.0.31 was released quite a while after 2.1 +kernel development began. The earliest Linux kernel in the 2.1 +development stream with SO_BINDTODEVICE is version 2.1.68. + +We have heard reports that you must still add routes to 255.255.255.255 +in order for the all-ones broadcast to work, even on 2.0.31 kernels. +In fact, you now need to add a route for each interface. Hopefully +the Linux kernel gurus will get this straight eventually. + + SCO + +SCO has the same problem as Linux (described earlier). The thing is, +SCO *really* doesn't want to let you add a host route to the all-ones +broadcast address. One technique that has been successful on some +versions of SCO is the very bizarre command: + + ifconfig net0 alias 10.1.1.1 netmask 8.0.0.0 + +Apparently this works because of an interaction between SCO's support +for network classes and the weird netmask. The 10.* network is just a +dummy that can generally be assumed to be safe. Don't ask why this +works. Just try it. If it works for you, great. If not, SCO is +supposedly adding hooks to support real DHCP service in a future +release - I have this on good authority from the people at SCO who do +*their* DHCP server and client. + + HP-UX + +HP-UX has the same problem with the all-ones broadcast address that +SCO and Linux have. One user reported that adding the following to +/etc/rc.config.d/netconf helped (you may have to modify this to suit +your local configuration): + +INTERFACE_NAME[0]=lan0 +IP_ADDRESS[0]=1.1.1.1 +SUBNET_MASK[0]=255.255.255.0 +BROADCAST_ADDRESS[0]="255.255.255.255" +LANCONFIG_ARGS[0]="ether" +DHCP_ENABLE[0]=0 + + ULTRIX + +Now that we have Ultrix packet filter support, the DHCP Distribution +on Ultrix should be pretty trouble-free. However, one thing you do +need to be aware of is that it now requires that the pfilt device be +configured into your kernel and present in /dev. If you type ``man +packetfilter'', you will get some information on how to configure your +kernel for the packet filter (if it isn't already) and how to make an +entry for it in /dev. + + FreeBSD + +Versions of FreeBSD prior to 2.2 have a bug in BPF support in that the +ethernet driver swaps the ethertype field in the ethernet header +downstream from BPF, which corrupts the output packet. If you are +running a version of FreeBSD prior to 2.2, and you find that dhcpd +can't communicate with its clients, you should #define BROKEN_FREEBSD_BPF +in site.h and recompile. + + NeXTSTEP + +The NeXTSTEP support uses the NeXTSTEP Berkeley Packet Filter +extension, which is not included in the base NextStep system. You +must install this extension in order to get dhcpd or dhclient to work. + + SUPPORT + +The Internet Software Consortium DHCP server is not a commercial +product, and is not supported in that sense. However, it has +attracted a fairly sizable following on the Internet, which means that +there are a lot of knowledgable users who may be able to help you if +you get stuck. These people generally read the dhcp-server@fugue.com +mailing list. + +If you are going to use dhcpd, you should probably subscribe to the +dhcp-server and dhcp-announce mailing lists. If you will be using +dhclient, you should subscribe to the dhcp-client mailing list. +PLEASE DO NOT send queries about non-isc clients to the dhcp-client +mailing list. If you're asking about them on an ISC mailing list, +it's probably because you're using the ISC DHCP server, so ask there. + +Please see http://www.fugue.com/dhcp/lists for details on how to +subscribe. If you don't have WorldWide Web access, you can send mail +to dhcp-request@fugue.com and tell me which lists you want to +subscribe to, but please use the web interface if you can, since I +have to handle the -request mailing list manually, and I will give you +the third degree if you make me do your subscription manually. + +PLEASE DO NOT SEND REQUESTS FOR SUPPORT DIRECTLY TO ME! The number of +people using the DHCP Distribution is sufficiently large that if I +take an interrupt every time any one of those people runs into +trouble, I will never get any more coding done. + +PLEASE DO NOT CALL ME ON THE PHONE FOR SUPPORT! Answering the phone +takes a lot more of my time and attention than answering email. If you +do call me on the phone, I will tell you to send email to the mailing +list, and I won't answer your question, so there's no point in doing +it. + + BUGS + +This release of the DHCP Distribution does not yet contain support for +DHCPINFORM. Support for DHCPINFORM will be present in the release at +a later time. DHCPINFORM is somewhat tangential to the main purpose +of the DHCP protocol, so this probably won't be a major problem for +most users. + +Vendor tags and User tags are not currently supported. + + |