@@ -33,7 +33,7 @@ CCOPTS = -D_GNU_SOURCE -O2 -Wstrict-prototypes -Wall
CFLAGS = $(CCOPTS) -I../include $(DEFINES)
YACCFLAGS = -d -t -v
-SUBDIRS=lib ip tc misc netem genl
+SUBDIRS=lib ip tc br misc netem genl
LIBNETLINK=../lib/libnetlink.a ../lib/libutil.a
LDLIBS += $(LIBNETLINK)
new file mode 100644
@@ -0,0 +1 @@
+br
new file mode 100644
@@ -0,0 +1,14 @@
+BROBJ = br.o fdb.o monitor.o link.o
+
+include ../Config
+
+all: br
+
+br: $(BROBJ) $(LIBNETLINK)
+
+install: all
+ install -m 0755 br $(DESTDIR)$(SBINDIR)
+
+clean:
+ rm -f $(BROBJ) br
+
new file mode 100644
@@ -0,0 +1,104 @@
+/*
+ * Get/set/delete bridge with netlink
+ *
+ * Authors: Stephen Hemminger <shemminger@vyatta.com>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <string.h>
+
+#include "SNAPSHOT.h"
+#include "utils.h"
+#include "br_common.h"
+
+struct rtnl_handle rth = { .fd = -1 };
+int resolve_hosts;
+int show_stats;
+int show_details;
+int timestamp;
+
+static void usage(void) __attribute__((noreturn));
+
+static void usage(void)
+{
+ fprintf(stderr,
+"Usage: br [ OPTIONS ] OBJECT { COMMAND | help }\n"
+"where OBJECT := { fdb | monitor }\n"
+" OPTIONS := { -V[ersion] | -s[tatistics] | -d[etails]\n" );
+ exit(-1);
+}
+
+static int do_help(int argc, char **argv)
+{
+ usage();
+}
+
+
+static const struct cmd {
+ const char *cmd;
+ int (*func)(int argc, char **argv);
+} cmds[] = {
+ { "fdb", do_fdb },
+ { "monitor", do_monitor },
+ { "help", do_help },
+ { 0 }
+};
+
+static int do_cmd(const char *argv0, int argc, char **argv)
+{
+ const struct cmd *c;
+
+ for (c = cmds; c->cmd; ++c) {
+ if (matches(argv0, c->cmd) == 0)
+ return c->func(argc-1, argv+1);
+ }
+
+ fprintf(stderr, "Object \"%s\" is unknown, try \"br help\".\n", argv0);
+ return -1;
+}
+
+int
+main(int argc, char **argv)
+{
+ while (argc > 1) {
+ char *opt = argv[1];
+ if (strcmp(opt,"--") == 0) {
+ argc--; argv++;
+ break;
+ }
+ if (opt[0] != '-')
+ break;
+ if (opt[1] == '-')
+ opt++;
+
+ if (matches(opt, "-help") == 0) {
+ usage();
+ } else if (matches(opt, "-Version") == 0) {
+ printf("br utility, 0.0\n");
+ exit(0);
+ } else if (matches(opt, "-stats") == 0 ||
+ matches(opt, "-statistics") == 0) {
+ ++show_stats;
+ } else if (matches(opt, "-details") == 0) {
+ ++show_details;
+ } else if (matches(opt, "-timestamp") == 0) {
+ ++timestamp;
+ } else {
+ fprintf(stderr, "Option \"%s\" is unknown, try \"br -help\".\n", opt);
+ exit(-1);
+ }
+ argc--; argv++;
+ }
+
+ if (rtnl_open(&rth, 0) < 0)
+ exit(1);
+
+ if (argc > 1)
+ return do_cmd(argv[1], argc-1, argv+1);
+
+ rtnl_close(&rth);
+ usage();
+}
new file mode 100644
@@ -0,0 +1,13 @@
+extern int print_linkinfo(const struct sockaddr_nl *who,
+ struct nlmsghdr *n,
+ void *arg);
+extern int print_fdb(const struct sockaddr_nl *who,
+ struct nlmsghdr *n, void *arg);
+
+extern int do_fdb(int argc, char **argv);
+extern int do_monitor(int argc, char **argv);
+
+extern int show_stats;
+extern int show_detail;
+extern int timestamp;
+extern struct rtnl_handle rth;
new file mode 100644
@@ -0,0 +1,245 @@
+/*
+ * Get/set/delete fdb table with netlink
+ *
+ * Authors: Stephen Hemminger <shemminger@vyatta.com>
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <time.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#include <linux/if_bridge.h>
+#include <linux/if_ether.h>
+#include <linux/neighbour.h>
+#include <string.h>
+
+#include "libnetlink.h"
+#include "br_common.h"
+#include "utils.h"
+
+int filter_index;
+
+static void usage(void)
+{
+ fprintf(stderr, "Usage: br fdb { add | del | replace } ADDR dev DEV\n");
+ fprintf(stderr, " br fdb {show} [ dev DEV ]\n");
+ exit(-1);
+}
+
+static const char *state_n2a(unsigned s)
+{
+ static char buf[32];
+
+ if (s & NUD_PERMANENT)
+ return "local";
+
+ if (s & NUD_NOARP)
+ return "static";
+
+ if (s & NUD_STALE)
+ return "stale";
+
+ if (s & NUD_REACHABLE)
+ return "";
+
+ sprintf(buf, "state=%#x", s);
+ return buf;
+}
+
+static char *fmt_time(char *b, size_t l, unsigned long tick)
+{
+ static int hz;
+
+ if (hz == 0)
+ hz = __get_user_hz();
+
+ snprintf(b, l, "%lu.%02lu", tick / hz, ((tick % hz) * hz) / 100);
+ return b;
+}
+
+int print_fdb(const struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
+{
+ FILE *fp = arg;
+ struct ndmsg *r = NLMSG_DATA(n);
+ int len = n->nlmsg_len;
+ struct rtattr * tb[NDA_MAX+1];
+ const __u8 *addr = NULL;
+ char b1[32];
+
+ len -= NLMSG_LENGTH(sizeof(*r));
+ if (len < 0) {
+ fprintf(stderr, "BUG: wrong nlmsg len %d\n", len);
+ return -1;
+ }
+
+ if (r->ndm_family != AF_BRIDGE)
+ return 0;
+
+ if (filter_index && filter_index != r->ndm_ifindex)
+ return 0;
+
+ parse_rtattr(tb, NDA_MAX, NDA_RTA(r),
+ n->nlmsg_len - NLMSG_LENGTH(sizeof(*r)));
+
+ if (n->nlmsg_type == RTM_DELNEIGH)
+ fprintf(fp, "Deleted ");
+
+ if (tb[NDA_LLADDR])
+ addr = RTA_DATA(tb[NDA_LLADDR]);
+ else {
+ fprintf(stderr, "missing lladdr\n");
+ return -1;
+ }
+
+ fprintf(fp, "%s\t%.2x:%.2x:%.2x:%.2x:%.2x:%.2x\t%s",
+ ll_index_to_name(r->ndm_ifindex),
+ addr[0], addr[1], addr[2],
+ addr[3], addr[4], addr[5],
+ state_n2a(r->ndm_state));
+
+ if (show_stats && tb[NDA_CACHEINFO]) {
+ struct nda_cacheinfo *ci = RTA_DATA(tb[NDA_CACHEINFO]);
+
+ fprintf(fp, "\t%8s", fmt_time(b1, sizeof(b1), ci->ndm_updated));
+ fprintf(fp, " %8s", fmt_time(b1, sizeof(b1), ci->ndm_used));
+ }
+ fprintf(fp, "\n");
+ fflush(fp);
+ return 0;
+}
+
+static int fdb_show(int argc, char **argv)
+{
+ char *filter_dev = NULL;
+
+ while (argc > 0) {
+ if (strcmp(*argv, "dev") == 0) {
+ NEXT_ARG();
+ if (filter_dev)
+ duparg("dev", *argv);
+ filter_dev = *argv;
+ }
+ argc--; argv++;
+ }
+
+ if (filter_dev) {
+ if ((filter_index = if_nametoindex(filter_dev)) == 0) {
+ fprintf(stderr, "Cannot find device \"%s\"\n", filter_dev);
+ return -1;
+ }
+ }
+
+ if (rtnl_wilddump_request(&rth, PF_BRIDGE, RTM_GETNEIGH) < 0) {
+ perror("Cannot send dump request");
+ exit(1);
+ }
+
+ printf("port\tmac addr\t\tflags%s\n",
+ show_stats ? "\t updated used" : "");
+
+ if (rtnl_dump_filter(&rth, print_fdb, stdout, NULL, NULL) < 0) {
+ fprintf(stderr, "Dump terminated\n");
+ exit(1);
+ }
+
+ return 0;
+}
+
+static int fdb_modify(int cmd, int flags, int argc, char **argv)
+{
+ struct {
+ struct nlmsghdr n;
+ struct ndmsg ndm;
+ char buf[256];
+ } req;
+ char *addr = NULL;
+ char *d = NULL;
+ char abuf[ETH_ALEN];
+
+ memset(&req, 0, sizeof(req));
+
+ req.n.nlmsg_len = NLMSG_LENGTH(sizeof(struct ndmsg));
+ req.n.nlmsg_flags = NLM_F_REQUEST|flags;
+ req.n.nlmsg_type = cmd;
+ req.ndm.ndm_family = PF_BRIDGE;
+ req.ndm.ndm_state = NUD_NOARP;
+
+ while (argc > 0) {
+ if (strcmp(*argv, "dev") == 0) {
+ NEXT_ARG();
+ d = *argv;
+ } else if (strcmp(*argv, "local") == 0) {
+ req.ndm.ndm_state = NUD_PERMANENT;
+ } else if (strcmp(*argv, "temp") == 0) {
+ req.ndm.ndm_state = NUD_REACHABLE;
+ } else {
+ if (strcmp(*argv, "to") == 0) {
+ NEXT_ARG();
+ }
+ if (matches(*argv, "help") == 0) {
+ NEXT_ARG();
+ }
+ if (addr)
+ duparg2("to", *argv);
+ addr = *argv;
+ }
+ argc--; argv++;
+ }
+
+ if (d == NULL || addr == NULL) {
+ fprintf(stderr, "Device and address are required arguments.\n");
+ exit(-1);
+ }
+
+ if (sscanf(addr, "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx",
+ abuf, abuf+1, abuf+2,
+ abuf+3, abuf+4, abuf+5) != 6) {
+ fprintf(stderr, "Invalid mac address %s\n", addr);
+ exit(-1);
+ }
+
+ addattr_l(&req.n, sizeof(req), NDA_LLADDR, abuf, ETH_ALEN);
+
+ req.ndm.ndm_ifindex = ll_name_to_index(d);
+ if (req.ndm.ndm_ifindex == 0) {
+ fprintf(stderr, "Cannot find device \"%s\"\n", d);
+ return -1;
+ }
+
+ if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0)
+ exit(2);
+
+ return 0;
+}
+
+int do_fdb(int argc, char **argv)
+{
+ ll_init_map(&rth);
+
+ if (argc > 0) {
+ if (matches(*argv, "add") == 0)
+ return fdb_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_EXCL, argc-1, argv+1);
+ if (matches(*argv, "change") == 0)
+ return fdb_modify(RTM_NEWNEIGH, NLM_F_REPLACE, argc-1, argv+1);
+
+ if (matches(*argv, "replace") == 0)
+ return fdb_modify(RTM_NEWNEIGH, NLM_F_CREATE|NLM_F_REPLACE, argc-1, argv+1);
+ if (matches(*argv, "delete") == 0)
+ return fdb_modify(RTM_DELNEIGH, 0, argc-1, argv+1);
+ if (matches(*argv, "show") == 0 ||
+ matches(*argv, "lst") == 0 ||
+ matches(*argv, "list") == 0)
+ return fdb_show(argc-1, argv+1);
+ if (matches(*argv, "help") == 0)
+ usage();
+ } else
+ return fdb_show(0, NULL);
+
+ fprintf(stderr, "Command \"%s\" is unknown, try \"ip neigh help\".\n", *argv);
+ exit(-1);
+}
new file mode 100644
@@ -0,0 +1,142 @@
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <time.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <netinet/in.h>
+#include <linux/if.h>
+#include <linux/if_bridge.h>
+#include <string.h>
+
+#include "utils.h"
+#include "br_common.h"
+
+static const char *port_states[] = {
+ [BR_STATE_DISABLED] = "disabled",
+ [BR_STATE_LISTENING] = "listening",
+ [BR_STATE_LEARNING] = "learning",
+ [BR_STATE_FORWARDING] = "forwarding",
+ [BR_STATE_BLOCKING] = "blocking",
+};
+
+extern char *if_indextoname (unsigned int __ifindex, char *__ifname);
+
+static void print_link_flags(FILE *fp, unsigned flags)
+{
+ fprintf(fp, "<");
+ if (flags & IFF_UP && !(flags & IFF_RUNNING))
+ fprintf(fp, "NO-CARRIER%s", flags ? "," : "");
+ flags &= ~IFF_RUNNING;
+#define _PF(f) if (flags&IFF_##f) { \
+ flags &= ~IFF_##f ; \
+ fprintf(fp, #f "%s", flags ? "," : ""); }
+ _PF(LOOPBACK);
+ _PF(BROADCAST);
+ _PF(POINTOPOINT);
+ _PF(MULTICAST);
+ _PF(NOARP);
+ _PF(ALLMULTI);
+ _PF(PROMISC);
+ _PF(MASTER);
+ _PF(SLAVE);
+ _PF(DEBUG);
+ _PF(DYNAMIC);
+ _PF(AUTOMEDIA);
+ _PF(PORTSEL);
+ _PF(NOTRAILERS);
+ _PF(UP);
+ _PF(LOWER_UP);
+ _PF(DORMANT);
+ _PF(ECHO);
+#undef _PF
+ if (flags)
+ fprintf(fp, "%x", flags);
+ fprintf(fp, "> ");
+}
+
+static const char *oper_states[] = {
+ "UNKNOWN", "NOTPRESENT", "DOWN", "LOWERLAYERDOWN",
+ "TESTING", "DORMANT", "UP"
+};
+
+static void print_operstate(FILE *f, __u8 state)
+{
+ if (state >= sizeof(oper_states)/sizeof(oper_states[0]))
+ fprintf(f, "state %#x ", state);
+ else
+ fprintf(f, "state %s ", oper_states[state]);
+}
+
+int print_linkinfo(const struct sockaddr_nl *who,
+ struct nlmsghdr *n, void *arg)
+{
+ FILE *fp = arg;
+ int len = n->nlmsg_len;
+ struct ifinfomsg *ifi = NLMSG_DATA(n);
+ struct rtattr * tb[IFLA_MAX+1];
+ char b1[IFNAMSIZ];
+
+ len -= NLMSG_LENGTH(sizeof(*ifi));
+ if (len < 0) {
+ fprintf(stderr, "Message too short!\n");
+ return -1;
+ }
+
+ if (!(ifi->ifi_family == AF_BRIDGE || ifi->ifi_family == AF_UNSPEC))
+ return 0;
+
+ parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), len);
+
+ if (tb[IFLA_IFNAME] == NULL) {
+ fprintf(stderr, "BUG: nil ifname\n");
+ return -1;
+ }
+
+ if (n->nlmsg_type == RTM_DELLINK)
+ fprintf(fp, "Deleted ");
+
+ fprintf(fp, "%d: %s ", ifi->ifi_index,
+ tb[IFLA_IFNAME] ? (char*)RTA_DATA(tb[IFLA_IFNAME]) : "<nil>");
+
+ if (tb[IFLA_OPERSTATE])
+ print_operstate(fp, *(__u8 *)RTA_DATA(tb[IFLA_OPERSTATE]));
+
+ if (tb[IFLA_LINK]) {
+ SPRINT_BUF(b1);
+ int iflink = *(int*)RTA_DATA(tb[IFLA_LINK]);
+
+ if (iflink == 0)
+ fprintf(fp, "@NONE: ");
+ else {
+ fprintf(fp, "@%s: ",
+ if_indextoname(iflink, b1));
+ }
+ } else {
+ fprintf(fp, ": ");
+ }
+
+ print_link_flags(fp, ifi->ifi_flags);
+
+ if (tb[IFLA_MTU])
+ fprintf(fp, "mtu %u ", *(int*)RTA_DATA(tb[IFLA_MTU]));
+
+ if (tb[IFLA_MASTER]) {
+ fprintf(fp, "master %s ",
+ if_indextoname(*(int*)RTA_DATA(tb[IFLA_MASTER]), b1));
+ }
+
+ if (tb[IFLA_PROTINFO]) {
+ uint8_t state = *(uint8_t *)RTA_DATA(tb[IFLA_PROTINFO]);
+ if (state <= BR_STATE_BLOCKING)
+ fprintf(fp, "state %s", port_states[state]);
+ else
+ fprintf(fp, "state (%d)", state);
+ }
+
+
+ fprintf(fp, "\n");
+ fflush(fp);
+ return 0;
+}
new file mode 100644
@@ -0,0 +1,138 @@
+/*
+ * brmonitor.c "br monitor"
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * Authors: Stephen Hemminger <shemminger@vyatta.com>
+ *
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <time.h>
+#include <sys/socket.h>
+#include <sys/time.h>
+#include <net/if.h>
+#include <netinet/in.h>
+#include <linux/if_bridge.h>
+#include <linux/neighbour.h>
+#include <string.h>
+
+#include "utils.h"
+#include "br_common.h"
+
+
+static void usage(void) __attribute__((noreturn));
+int prefix_banner;
+
+static void usage(void)
+{
+ fprintf(stderr, "Usage: br monitor\n");
+ exit(-1);
+}
+
+static int show_mark(FILE *fp, const struct nlmsghdr *n)
+{
+ char *tstr;
+ time_t secs = ((__u32*)NLMSG_DATA(n))[0];
+ long usecs = ((__u32*)NLMSG_DATA(n))[1];
+ tstr = asctime(localtime(&secs));
+ tstr[strlen(tstr)-1] = 0;
+ fprintf(fp, "Timestamp: %s %lu us\n", tstr, usecs);
+ return 0;
+}
+
+int accept_msg(const struct sockaddr_nl *who,
+ struct nlmsghdr *n, void *arg)
+{
+ FILE *fp = arg;
+
+ if (timestamp)
+ print_timestamp(fp);
+
+ switch (n->nlmsg_type) {
+ case RTM_NEWLINK:
+ case RTM_DELLINK:
+ if (prefix_banner)
+ fprintf(fp, "[LINK]");
+
+ return print_linkinfo(who, n, arg);
+
+ case RTM_NEWNEIGH:
+ case RTM_DELNEIGH:
+ if (prefix_banner)
+ fprintf(fp, "[NEIGH]");
+ return print_fdb(who, n, arg);
+
+ case 15:
+ return show_mark(fp, n);
+
+ default:
+ return 0;
+ }
+
+
+}
+
+int do_monitor(int argc, char **argv)
+{
+ char *file = NULL;
+ unsigned groups = ~RTMGRP_TC;
+ int llink=0;
+ int lneigh=0;
+
+ rtnl_close(&rth);
+
+ while (argc > 0) {
+ if (matches(*argv, "file") == 0) {
+ NEXT_ARG();
+ file = *argv;
+ } else if (matches(*argv, "link") == 0) {
+ llink=1;
+ groups = 0;
+ } else if (matches(*argv, "fdb") == 0) {
+ lneigh = 1;
+ groups = 0;
+ } else if (strcmp(*argv, "all") == 0) {
+ groups = ~RTMGRP_TC;
+ prefix_banner=1;
+ } else if (matches(*argv, "help") == 0) {
+ usage();
+ } else {
+ fprintf(stderr, "Argument \"%s\" is unknown, try \"br monitor help\".\n", *argv);
+ exit(-1);
+ }
+ argc--; argv++;
+ }
+
+ if (llink)
+ groups |= nl_mgrp(RTNLGRP_LINK);
+
+ if (lneigh) {
+ groups |= nl_mgrp(RTNLGRP_NEIGH);
+ }
+
+ if (file) {
+ FILE *fp;
+ fp = fopen(file, "r");
+ if (fp == NULL) {
+ perror("Cannot fopen");
+ exit(-1);
+ }
+ return rtnl_from_file(fp, accept_msg, stdout);
+ }
+
+ if (rtnl_open(&rth, groups) < 0)
+ exit(1);
+ ll_init_map(&rth);
+
+ if (rtnl_listen(&rth, accept_msg, stdout) < 0)
+ exit(2);
+
+ return 0;
+}
+
new file mode 100644
@@ -0,0 +1,177 @@
+.TH BR 8 "4 October 2011" "iproute2" "Linux"
+.SH NAME
+br \- show / manipulate bridge addresses and devices
+.SH SYNOPSIS
+
+.ad l
+.in +8
+.ti -8
+.B br
+.RI "[ " OPTIONS " ] " OBJECT " { " COMMAND " | "
+.BR help " }"
+.sp
+
+.ti -8
+.IR OBJECT " := { "
+.BR fdb " | " monitor " }"
+.sp
+
+.ti -8
+.IR OPTIONS " := { "
+\fB\-V\fR[\fIersion\fR] |
+\fB\-s\fR[\fItatistics\fR]
+
+.ti -8
+.BR "br fdb" " { " add " | " del " | " change " | " replace " } "
+.I LLADDR
+.B dev
+.IR DEV " { "
+.BR local " | " temp " }"
+
+.ti -8
+.BR "br fdb" " [ " show " ] [ "
+.B dev
+.IR DEV " ]"
+
+.ti -8
+.BR "br monitor" " [ " all " | " neigh " | " link " ]"
+
+.SH OPTIONS
+
+.TP
+.BR "\-V" , " -Version"
+print the version of the
+.B ip
+utility and exit.
+
+.TP
+.BR "\-s" , " \-stats", " \-statistics"
+output more information. If the option
+appears twice or more, the amount of information increases.
+As a rule, the information is statistics or some time values.
+
+
+.SH BR - COMMAND SYNTAX
+
+.SS
+.I OBJECT
+
+.TP
+.B fdb
+- Forwarding Database entry.
+
+.SS
+.I COMMAND
+
+Specifies the action to perform on the object.
+The set of possible actions depends on the object type.
+As a rule, it is possible to
+.BR "add" , " delete"
+and
+.B show
+(or
+.B list
+) objects, but some objects do not allow all of these operations
+or have some additional commands. The
+.B help
+command is available for all objects. It prints
+out a list of available commands and argument syntax conventions.
+.sp
+If no command is given, some default command is assumed.
+Usually it is
+.B list
+or, if the objects of this class cannot be listed,
+.BR "help" .
+
+.SH br fdb - forwarding database management
+
+.B fdb
+objects contain known ethernet addresses fona link.
+
+.P
+The corresponding commands display fdb entries, add new entries,
+and delete old ones.
+
+.SS br fdb add - add a new neighbour entry
+.SS br fdb change - change an existing entry
+.SS br fdb replace - add a new entry or change an existing one
+
+These commands create new neighbour records or update existing ones.
+
+.TP
+.BI "ADDRESS"
+the Ethernet MAC address.
+
+.TP
+.BI dev " NAME"
+the interface to which this address is associated.
+
+.TP
+.in +8
+.B local
+- the address is associated with a local interface on the system
+and is never forwarded.
+.sp
+
+.B temp
+- the address is a dynamic entry, and will be removed if not used.
+.sp
+
+.in -8
+
+.SS br fdb delete - delete a forwarding database entry
+This command removes an existing fdb entry.
+
+.PP
+The arguments are the same as with
+.BR "br fdb add" ,
+
+.SS br fdb show - list forwarding entries.
+
+This commands displays current forwarding table.
+
+.PP
+With the
+.B -statistics
+option, the command becomes verbose. It prints out the last updated
+and last used time for each entry.
+
+.SH br monitor - state monitoring
+
+The
+.B br
+utility can monitor the state of devices and addresses
+continuously. This option has a slightly different format.
+Namely, the
+.B monitor
+command is the first in the command line and then the object list follows:
+
+.BR "br monitor" " [ " all " |"
+.IR LISTofOBJECTS " ]"
+
+.I OBJECT-LIST
+is the list of object types that we want to monitor.
+It may contain
+.BR link ", and " fdb "."
+If no
+.B file
+argument is given,
+.B ip
+opens RTNETLINK, listens on it and dumps state changes in the format
+described in previous sections.
+
+.P
+If a file name is given, it does not listen on RTNETLINK,
+but opens the file containing RTNETLINK messages saved in binary format
+and dumps them. Such a history file can be generated with the
+
+.SH HISTORY
+.B br
+was written by Stephen Hemminger and uses kernel facilities added in Linux 3.0
+.SH SEE ALSO
+.BR ip (8)
+.br
+.RB "Please direct bugreports and patches to: " <netdev@vger.kernel.org>
+
+.SH AUTHOR
+Original Manpage by Stephen Hemminger