mirror of
https://gitlab.isc.org/isc-projects/dhcp
synced 2025-08-22 09:57:20 +00:00
- Merge dhcrelay6 into dhcrelay
- Prep for 4.1.0a2 release
This commit is contained in:
Evan Hunt
parent
ffbaa8801e
commit
7de20a9518
2
README
2
README
@ -1,6 +1,6 @@
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Internet Systems Consortium DHCP Distribution
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Version 4.1.0a2
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4 June 2008
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12 June 2008
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README FILE
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7
RELNOTES
7
RELNOTES
@ -1,6 +1,6 @@
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Internet Systems Consortium DHCP Distribution
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Version 4.1.0a2
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4 June 2008
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12 June 2008
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Release Notes
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@ -15,7 +15,7 @@ in DHCP 4.0.x. These include:
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- IA_TA address support
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- A basic DHCPv6 relay agent, dhcrelay6
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- A basic DHCPv6 relay agent
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- Basic and partial DHCPv6 leasequery support
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@ -93,6 +93,9 @@ work on other platforms. Please report any problems and suggested fixes to
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- Support "-1" argument in DHCPv6.
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- Merge DHCPv6-only "dhcrelay6" into general-purpose "dhcrelay" (use
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"-6" option to select DHCPv6 mode).
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Changes since 4.0.0 (new features)
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- Added DHCPv6 rapid commit support.
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@ -1215,7 +1215,8 @@ discover_interfaces(int state) {
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if_register_send(tmp);
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#ifdef DHCPv6
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} else {
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if (state == DISCOVER_SERVER) {
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if ((state == DISCOVER_SERVER) ||
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(state == DISCOVER_RELAY)) {
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if_register6(tmp, 1);
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} else {
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if_register6(tmp, 0);
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@ -3806,14 +3806,14 @@ do_packet6(struct interface_info *interface, const char *packet,
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}
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/* IPv4 information, already set to 0 */
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/* decoded_packet->raw = NULL; */
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/* decoded_packet->packet_length = 0; */
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/* decoded_packet->packet_type = 0; */
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/* memset(&decoded_packet->haddr, 0, sizeof(decoded_packet->haddr)); */
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/* decoded_packet->circuit_id = NULL; */
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/* decoded_packet->circuit_id_len = 0; */
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/* decoded_packet->remote_id = NULL; */
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/* decoded_packet->remote_id_len = 0; */
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decoded_packet->raw = (struct dhcp_packet *) packet;
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decoded_packet->packet_length = (unsigned) len;
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decoded_packet->client_port = from_port;
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decoded_packet->client_addr = *from;
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interface_reference(&decoded_packet->interface, interface, MDL);
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@ -95,6 +95,40 @@ void if_reinitialize_receive (info)
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#if defined (USE_SOCKET_SEND) || \
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defined (USE_SOCKET_RECEIVE) || \
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defined (USE_SOCKET_FALLBACK)
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#ifdef DHCPv6
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/* Get the best (i.e., global or at least site-local) address
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of the interface. */
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static isc_result_t
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get_ifaddr6(struct interface_info *info, struct in6_addr *ifaddr6) {
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int i;
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struct in6_addr *a, *ba = NULL;
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for (i = 0; i < info->v6address_count; i++) {
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a = &info->v6addresses[i];
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if (IN6_IS_ADDR_UNSPECIFIED(a) ||
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IN6_IS_ADDR_LOOPBACK(a) ||
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IN6_IS_ADDR_MULTICAST(a) ||
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IN6_IS_ADDR_LINKLOCAL(a) ||
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IN6_IS_ADDR_V4MAPPED(a))
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continue;
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if (ba == NULL)
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ba = a;
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if (!IN6_IS_ADDR_SITELOCAL(a)) {
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ba = a;
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break;
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}
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}
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if (ba == NULL)
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return ISC_R_NOTFOUND;
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*ifaddr6 = *ba;
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return ISC_R_SUCCESS;
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}
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#endif /* DHCPv6 */
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/* Generic interface registration routine... */
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int
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if_register_socket(struct interface_info *info, int family, int do_multicast) {
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@ -128,8 +162,21 @@ if_register_socket(struct interface_info *info, int family, int do_multicast) {
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memcpy(&addr->sin6_addr,
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&local_address6,
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sizeof(addr->sin6_addr));
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#ifdef HAVE_SA_LEN
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addr->sin6_len = sizeof(*addr);
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#endif
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name_len = sizeof(*addr);
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domain = PF_INET6;
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if ((info->flags & INTERFACE_STREAMS) == INTERFACE_UPSTREAM) {
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struct in6_addr ifaddr6;
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do_multicast = 0;
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if (get_ifaddr6(info, &ifaddr6) == ISC_R_SUCCESS) {
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memcpy(&addr->sin6_addr,
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&ifaddr6,
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sizeof(addr->sin6_addr));
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}
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}
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} else {
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#else
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{
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@ -140,6 +187,9 @@ if_register_socket(struct interface_info *info, int family, int do_multicast) {
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memcpy(&addr->sin_addr,
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&local_address,
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sizeof(addr->sin_addr));
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#ifdef HAVE_SA_LEN
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addr->sin_len = sizeof(*addr);
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#endif
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name_len = sizeof(*addr);
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domain = PF_INET;
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}
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@ -246,11 +296,21 @@ if_register_socket(struct interface_info *info, int family, int do_multicast) {
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All_DHCP_Servers);
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}
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mreq.ipv6mr_interface = if_nametoindex(info->name);
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if (setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP,
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&mreq, sizeof(mreq)) < 0) {
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if (((info->flags & INTERFACE_DOWNSTREAM) == 0) &&
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(setsockopt(sock, IPPROTO_IPV6, IPV6_JOIN_GROUP,
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&mreq, sizeof(mreq)) < 0)) {
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log_fatal("setsockopt: IPV6_JOIN_GROUP: %m");
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}
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}
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if ((family == AF_INET6) &&
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((info->flags & INTERFACE_UPSTREAM) != 0)) {
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int hop_limit = 32;
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if (setsockopt(sock, IPPROTO_IPV6, IPV6_MULTICAST_HOPS,
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&hop_limit, sizeof(int)) < 0) {
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log_fatal("setsockopt: IPV6_MULTICAST_HOPS: %m");
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}
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}
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#endif /* DHCPv6 */
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if (strcmp(info->name, "fallback") != 0)
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@ -1141,6 +1141,9 @@ struct interface_info {
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#define INTERFACE_REQUESTED 1
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#define INTERFACE_AUTOMATIC 2
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#define INTERFACE_RUNNING 4
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#define INTERFACE_DOWNSTREAM 8
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#define INTERFACE_UPSTREAM 16
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#define INTERFACE_STREAMS (INTERFACE_DOWNSTREAM | INTERFACE_UPSTREAM)
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/* Only used by DHCP client code. */
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struct client_state *client;
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@ -1325,6 +1328,10 @@ typedef unsigned char option_mask [16];
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#define _PATH_DHCRELAY_PID LOCALSTATEDIR"/run/dhcrelay.pid"
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#endif
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#ifndef _PATH_DHCRELAY6_PID
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#define _PATH_DHCRELAY6_PID LOCALSTATEDIR"/run/dhcrelay6.pid"
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#endif
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#ifndef DHCPD_LOG_FACILITY
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#define DHCPD_LOG_FACILITY LOG_DAEMON
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#endif
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@ -2646,19 +2653,6 @@ int parse_ip_addr PROTO ((struct parse *, struct iaddr *));
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int parse_ip_addr_with_subnet(struct parse *, struct iaddrmatch *);
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void parse_reject_statement PROTO ((struct parse *, struct client_config *));
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/* dhcrelay.c */
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void relay PROTO ((struct interface_info *, struct dhcp_packet *, unsigned,
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unsigned int, struct iaddr, struct hardware *));
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int strip_relay_agent_options PROTO ((struct interface_info *,
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struct interface_info **,
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struct dhcp_packet *, unsigned));
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int find_interface_by_agent_option PROTO ((struct dhcp_packet *,
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struct interface_info **,
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u_int8_t *, int));
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int add_relay_agent_options PROTO ((struct interface_info *,
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struct dhcp_packet *,
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unsigned, struct in_addr));
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/* icmp.c */
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OMAPI_OBJECT_ALLOC_DECL (icmp_state, struct icmp_state, dhcp_type_icmp)
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extern struct icmp_state *icmp_state;
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@ -2,7 +2,7 @@ AM_CPPFLAGS = -DLOCALSTATEDIR='"@localstatedir@"'
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sbin_PROGRAMS = dhcrelay
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dhcrelay_SOURCES = dhcrelay.c
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dhcrelay_LDADD = ../common/libdhcp.a ../omapip/libomapi.a ../dst/libdst.a
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dhcrelay_LDADD = ../common/libdhcp.a ../omapip/libomapi.a ../dst/libdst.a ../minires/libres.a
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man_MANS = dhcrelay.8
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EXTRA_DIST = $(man_MANS)
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@ -50,7 +50,7 @@ PROGRAMS = $(sbin_PROGRAMS)
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am_dhcrelay_OBJECTS = dhcrelay.$(OBJEXT)
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dhcrelay_OBJECTS = $(am_dhcrelay_OBJECTS)
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dhcrelay_DEPENDENCIES = ../common/libdhcp.a ../omapip/libomapi.a \
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../dst/libdst.a
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../dst/libdst.a ../minires/libres.a
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DEFAULT_INCLUDES = -I. -I$(srcdir) -I$(top_builddir)/includes
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depcomp = $(SHELL) $(top_srcdir)/depcomp
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am__depfiles_maybe = depfiles
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@ -143,7 +143,7 @@ sysconfdir = @sysconfdir@
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target_alias = @target_alias@
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AM_CPPFLAGS = -DLOCALSTATEDIR='"@localstatedir@"'
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dhcrelay_SOURCES = dhcrelay.c
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dhcrelay_LDADD = ../common/libdhcp.a ../omapip/libomapi.a ../dst/libdst.a
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dhcrelay_LDADD = ../common/libdhcp.a ../omapip/libomapi.a ../dst/libdst.a ../minires/libres.a
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man_MANS = dhcrelay.8
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EXTRA_DIST = $(man_MANS)
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all: all-am
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321
relay/dhcrelay.8
321
relay/dhcrelay.8
@ -27,7 +27,7 @@
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.\" see ``http://www.isc.org/isc''. To learn more about Vixie
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.\" Enterprises, see ``http://www.vix.com''.
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.\"
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.\" $Id: dhcrelay.8,v 1.14 2007/05/19 19:16:26 dhankins Exp $
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.\" $Id: dhcrelay.8,v 1.15 2008/06/13 00:55:53 each Exp $
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.\"
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.TH dhcrelay 8
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.SH NAME
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@ -35,28 +35,16 @@ dhcrelay - Dynamic Host Configuration Protocol Relay Agent
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.SH SYNOPSIS
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.B dhcrelay
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[
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.B -4
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]
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[
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.B -dqaD
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]
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[
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.B -p
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.I port
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]
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[
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.B -d
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]
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[
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.B -q
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]
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[
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.B -i
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.I if0
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[
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.B ...
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.B -i
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.I ifN
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]
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]
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[
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.B -a
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]
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[
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.B -c
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.I count
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]
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@ -65,9 +53,6 @@ dhcrelay - Dynamic Host Configuration Protocol Relay Agent
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.I length
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]
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[
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.B -D
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]
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[
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.B -m
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.I append
|
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|
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@ -77,169 +62,171 @@ dhcrelay - Dynamic Host Configuration Protocol Relay Agent
|
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|
|
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.I discard
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]
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[
|
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.B -i
|
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.I interface0
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[
|
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.B ...
|
||||
.B -i
|
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.I interfaceN
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]
|
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]
|
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.I server0
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[
|
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.I ...serverN
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]
|
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.PP
|
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.B dhcrelay -6
|
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[
|
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.B -dqI
|
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]
|
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[
|
||||
.B -p
|
||||
.I port
|
||||
]
|
||||
[
|
||||
.B -c
|
||||
.I count
|
||||
]
|
||||
.B -l
|
||||
.I lower0
|
||||
[
|
||||
.B ...
|
||||
.B -l
|
||||
.I lowerN
|
||||
]
|
||||
.B -u
|
||||
.I upper0
|
||||
[
|
||||
.B ...
|
||||
.B -u
|
||||
.I upperN
|
||||
]
|
||||
.SH DESCRIPTION
|
||||
The Internet Systems Consortium DHCP Relay Agent, dhcrelay, provides a
|
||||
means for relaying DHCP and BOOTP requests from a subnet to which
|
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no DHCP server is directly connected to one or more DHCP servers on other
|
||||
subnets.
|
||||
no DHCP server is directly connected to one or more DHCP servers on
|
||||
other subnets. It supports both DHCPv4/BOOTP and DHCPv6 protocols.
|
||||
.SH OPERATION
|
||||
.PP
|
||||
The DHCP Relay Agent listens for DHCP and BOOTP queries and responses.
|
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When a query is received from a client, dhcrelay forwards it to the
|
||||
list of DHCP servers specified on the command line. When a reply is
|
||||
received from a server, it is broadcast or unicast (according to the
|
||||
relay agent's ability or the client's request) on the network from
|
||||
which the original request came.
|
||||
The DHCP Relay Agent listens for DHCPv4 or DHCPv6 queries from clients or
|
||||
other relay agents on one or more interfaces, passing them along to
|
||||
``upstream'' servers or relay agents as specified on the command line.
|
||||
When a reply is received from upstream, it is multicast or unicast back
|
||||
downstream to the source of the original request.
|
||||
.SH COMMAND LINE
|
||||
.PP
|
||||
The names of the network interfaces that dhcrelay should attempt to
|
||||
configure may be specified on the command line using the
|
||||
.B -i
|
||||
option. If no interface names
|
||||
are specified on the command line dhcrelay will identify all network
|
||||
interfaces, elimininating non-broadcast interfaces if possible, and
|
||||
attempt to configure each interface.
|
||||
.PP
|
||||
The
|
||||
.B -i
|
||||
flag can be used to specify the network interfaces on which the relay
|
||||
agent should listen. In general, it must listen not only on those
|
||||
network interfaces to which clients are attached, but also on those
|
||||
network interfaces to which the server (or the router that reaches the
|
||||
server) is attached. However, in some cases it may be necessary to
|
||||
exclude some networks; in this case, you must list all those network
|
||||
interfaces that should \fInot\fR be excluded using the \fB-i\fR flag.
|
||||
.PP
|
||||
In some cases it
|
||||
.I is
|
||||
helpful for the relay agent to forward requests from networks on which
|
||||
a DHCP server is running to other DHCP servers. This would be the
|
||||
case if two DHCP servers on different networks were being used to
|
||||
provide backup service for each other's networks.
|
||||
.PP
|
||||
If dhcrelay should listen and transmit on a port other than the
|
||||
standard (port 67), the
|
||||
.B -p
|
||||
flag may used. It should be followed by the udp port number that
|
||||
dhcrelay should use. This is mostly useful for debugging purposes.
|
||||
.PP
|
||||
Dhcrelay will normally run in the foreground until it has configured
|
||||
an interface, and then will revert to running in the background.
|
||||
To force dhcrelay to always run as a foreground process, the
|
||||
.B -d
|
||||
flag should be specified. This is useful when running dhcrelay under
|
||||
a debugger, or when running it out of inittab on System V systems.
|
||||
.PP
|
||||
Dhcrelay will normally print its network configuration on startup.
|
||||
This can be unhelpful in a system startup script - to disable this
|
||||
behaviour, specify the
|
||||
.B -q
|
||||
flag.
|
||||
.SH RELAY AGENT INFORMATION OPTIONS
|
||||
If the
|
||||
.B -a
|
||||
flag is set the relay agent will append an agent option field to each
|
||||
request before forwarding it to the server. Agent option fields in
|
||||
responses sent from servers to clients will be stripped before
|
||||
forwarding such responses back to the client.
|
||||
.PP
|
||||
The agent option field will contain two agent options: the Circuit ID
|
||||
suboption and the Remote ID suboption. Currently, the Circuit ID will
|
||||
be the printable name of the interface on which the client request was
|
||||
received. The client supports inclusion of a Remote ID suboption as
|
||||
well, but this is not used by default.
|
||||
.PP
|
||||
When forwarding packets, dhcrelay discards packets which have reached a hop
|
||||
count of 10. If a lower or higher threshold (up to 255) is desired, depending
|
||||
on your environment, you can specify the max hop count threshold as a number
|
||||
following the
|
||||
.B -c
|
||||
\fIProtocol selection options:\fR
|
||||
.TP
|
||||
-6
|
||||
Run dhcrelay as a DHCPv6 relay agent. Incompatible with the \fB-4\fR
|
||||
option.
|
||||
.TP
|
||||
-4
|
||||
Run dhcrelay as a DHCPv4/BOOTP relay agent. This is the default mode of
|
||||
operation, so the argument is not necessary, but may be specified for
|
||||
clarity. Incompatible with \fB-6\fR.
|
||||
.PP
|
||||
Relay Agent options are added to a DHCP packet without the knowledge
|
||||
of the DHCP client. The client may have filled the DHCP packet
|
||||
option buffer completely, in which case there theoretically isn't any
|
||||
space to add Agent options. However, the DHCP server may be able to
|
||||
handle a much larger packet than most DHCP clients would send. The
|
||||
current Agent Options draft requires that the relay agent use a
|
||||
maximum packet size of 576 bytes.
|
||||
\fISpecifying DHCPv4/BOOTP servers\fR
|
||||
.PP
|
||||
It is recommended that with the Internet Systems Consortium DHCP
|
||||
server, the maximum packet size be set to about 1400, allowing plenty
|
||||
of extra space in which the relay agent can put the agent option
|
||||
field, while still fitting into the Ethernet MTU size. This can be
|
||||
done by specifying the
|
||||
.B -A
|
||||
flag, followed by the desired maximum packet size (e.g., 1400).
|
||||
In DHCPv4 mode, a list of one or more server addresses must be specified on
|
||||
the command line, to which DHCP/BOOTP queries should be relayed.
|
||||
.PP
|
||||
Note that this is reasonably safe to do even if the MTU between the
|
||||
server and the client is less than 1500, as long as the hosts on which
|
||||
the server and client are running support IP fragmentation (and they
|
||||
should). With some knowledge as to how large the agent options might
|
||||
get in a particular configuration, this parameter can be tuned as
|
||||
finely as necessary.
|
||||
\fIOptions available for both DHCPv4 and DHCPv6:\fR
|
||||
.TP
|
||||
-c COUNT
|
||||
Maximum hop count. When forwarding packets, dhcrelay discards packets
|
||||
which have reached a hop count of COUNT. Default is 10. Maximum is 255.
|
||||
.TP
|
||||
-d
|
||||
Force dhcrelay to run as a foreground process. Useful when running
|
||||
dhcrelay under a debugger, or running out of inittab on System V systems.
|
||||
.TP
|
||||
-p PORT
|
||||
Listen and transmit on port PORT. This is mostly useful for debugging
|
||||
purposes. Default is port 67 for DHCPv4/BOOTP, or port 547 for DHCPv6.
|
||||
.TP
|
||||
-q
|
||||
Quiet mode. Prevents dhcrelay6 from printing its network configuration
|
||||
on startup.
|
||||
.PP
|
||||
It is possible for a relay agent to receive a packet which already
|
||||
contains an agent option field. If this packet does not have a giaddr
|
||||
set, the standard requires that the packet be discarded.
|
||||
\fIOptions available in DHCPv4 mode only:\fR
|
||||
.TP
|
||||
-a
|
||||
Append an agent option field to each request before forwarding it to
|
||||
the server. Agent option fields in responses sent from servers to
|
||||
clients will be stripped before forwarding such responses back to the
|
||||
client. The agent option field will contain two agent options: the Circuit
|
||||
ID suboption and the Remote ID suboption. Currently, the Circuit ID will
|
||||
be the printable name of the interface on which the client request was
|
||||
received. The client supports inclusion of a Remote ID suboption as well,
|
||||
but this is not used by default.
|
||||
.TP
|
||||
-A LENGTH
|
||||
Specify the maximum packet size to send to a DHCPv4/BOOTP server. This
|
||||
might be done to allow sufficient space for addition of relay agent
|
||||
options while still fitting into the Ethernet MTU size.
|
||||
.TP
|
||||
-D
|
||||
Drop packets from upstream servers if they contain Relay Agent
|
||||
Information options that indicate they were generated in response to
|
||||
a query that came via a different relay agent. If this option is not
|
||||
specified, such packets will be relayed anyway.
|
||||
.TP
|
||||
-i \fIifname\fR
|
||||
Listen for DHCPv4/BOOTP queries on interface \fIifname\fR. Multiple
|
||||
interfaces may be specified by using more than one \fB-i\fR option. If
|
||||
no interfaces are specified on the command line, dhcrelay will identify
|
||||
all network interfaces, eliminating non-broadcast interfaces if possible,
|
||||
and attempt to listen on all of them.
|
||||
.TP
|
||||
-m \fIappend\fR|\fIreplace\fR|\fIforward\fR|\fIdiscard\fR
|
||||
Control the handling of incoming DHCPv4 packets which already contain
|
||||
relay agent options. If such a packet does not have \fIgiaddr\fR set in
|
||||
its header, the DHCP standard requires that the packet be discarded.
|
||||
However, if \fIgiaddr\fR is set, the relay agent may handle the situation
|
||||
in four ways: It may \fIappend\fR its own set of relay options to the
|
||||
packet, leaving the supplied option field intact; it may \fIreplace\fR the
|
||||
existing agent option field; it may \fIforward\fR the packet unchanged; or,
|
||||
it may \fIdiscard\fR it.
|
||||
.PP
|
||||
If giaddr is set, the server may handle the situation in one of four
|
||||
ways: it may
|
||||
.I append
|
||||
its own set of relay options to the packet, leaving the
|
||||
supplied option field intact. It may
|
||||
.I replace
|
||||
the existing agent option field.
|
||||
It may
|
||||
.I forward
|
||||
the packet unchanged. Or, it may
|
||||
.I discard
|
||||
it.
|
||||
\fIOptions available in DHCPv6 mode only:\fR
|
||||
.TP
|
||||
-I
|
||||
Force use of the DHCPv6 Interface-ID option. This option is
|
||||
automatically sent when there are two or more downstream interfaces
|
||||
in use, to disambiguate between them. The \fB-I\fR option causes
|
||||
dhcrelay to send the option even if there is only one downstream
|
||||
interface.
|
||||
.TP
|
||||
-l [\fIaddress%\fR]\fIifname\fR[\fI#index\fR]
|
||||
Specifies the ``lower'' network interface for DHCPv6 relay mode: the
|
||||
interface on which queries will be received from clients or from other
|
||||
relay agents. At least one \fB-l\fR option must be included in the command
|
||||
line when running in DHCPv6 mode. The interface name \fIifname\fR is a
|
||||
mandatory parameter. The link address can be specified by \fIaddress%\fR;
|
||||
if it isn't, dhcrelay will use the first non-link-local address configured
|
||||
on the interface. The optional \fI#index\fR parameter specifies the
|
||||
interface index.
|
||||
.TP
|
||||
-u [\fIaddress%\fR]\fIifname\fR
|
||||
Specifies the ``upper'' network interface for DHCPv6 relay mode: the
|
||||
interface to which queries from clients and other relay agents should be
|
||||
forwarded. At least one \fB-u\fR option must be included in the command
|
||||
line when running in DHCPv6 mode. The interface name \fIifname\fR is a
|
||||
mandatory parameter. The destination unicast or multicast address can be
|
||||
specified by \fIaddress%\fR; if not specified, the relay agent will forward
|
||||
to the DHCPv6 \fIAll_DHCP_Relay_Agents_and_Servers\fR multicast address.
|
||||
.PP
|
||||
Which of these behaviours is followed by the Internet Systems
|
||||
Consortium DHCP Relay Agent may be configured with the
|
||||
.B -m
|
||||
flag, followed by one of the four keywords specified in
|
||||
.I italics
|
||||
above.
|
||||
.PP
|
||||
When the relay agent receives a reply from a server that it's supposed
|
||||
to forward to a client, and Relay Agent Information option processing
|
||||
is enabled, the relay agent scans the packet for Relay Agent
|
||||
Information options and removes them. As it's scanning, if it finds
|
||||
a Relay Agent Information option field containing an Agent ID
|
||||
suboption that matches one of its IP addresses, that option is
|
||||
recognized as its own. If no such option is found, the relay agent
|
||||
can either drop the packet, or relay it anyway. If the
|
||||
.B -D
|
||||
option is specified, all packets that don't contain a match will be
|
||||
dropped.
|
||||
.SH SPECIFYING DHCP SERVERS
|
||||
The name or IP address of at least one DHCP server to which DHCP and
|
||||
BOOTP requests should be relayed must be specified on the command
|
||||
line.
|
||||
It is possible to specify the same interface with different addresses
|
||||
more than once, and even, when the system supports it, to use the same
|
||||
interface as both upper and lower interfaces.
|
||||
.SH SEE ALSO
|
||||
dhclient(8), dhcpd(8), RFC2132, RFC2131, draft-ietf-dhc-agent-options-03.txt.
|
||||
dhclient(8), dhcpd(8), RFC3315, RFC2132, RFC2131.
|
||||
.SH BUGS
|
||||
It should be possible for the user to define the Circuit ID and Remote
|
||||
ID values on a per-interface basis.
|
||||
.PP
|
||||
The relay agent should not relay packets received on a physical
|
||||
network to DHCP servers on the same physical network - if they do, the
|
||||
server will receive duplicate packets. In order to fix this,
|
||||
however, the relay agent needs to be able to learn about the network
|
||||
topology, which requires that it have a configuration file.
|
||||
.SH AUTHOR
|
||||
.B dhcrelay(8)
|
||||
has been written for Internet Systems Consortium
|
||||
by Ted Lemon in cooperation with Vixie
|
||||
Enterprises. To learn more about Internet Systems Consortium,
|
||||
see
|
||||
.B http://www.isc.org/isc.
|
||||
To learn more about Vixie
|
||||
Enterprises, see
|
||||
.B http://www.vix.com.
|
||||
Using the same interface on both upper and lower sides may cause
|
||||
loops, so when running this way, the maximum hop count should be set
|
||||
to a low value.
|
||||
.PP
|
||||
The loopback interface is not (yet) recognized as a valid interface.
|
||||
|
||||
1323
relay/dhcrelay.c
1323
relay/dhcrelay.c
File diff suppressed because it is too large
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Reference in New Issue
Block a user