1.\" Copyright (c) 1983, 1990, 1992, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 4. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)netstat.1 8.8 (Berkeley) 4/18/94 29.\" $FreeBSD$ 30.\" 31.Dd March 10, 2013 32.Dt NETSTAT 1 33.Os 34.Sh NAME 35.Nm netstat 36.Nd show network status 37.Sh DESCRIPTION 38The 39.Nm 40command symbolically displays the contents of various network-related 41data structures. 42There are a number of output formats, 43depending on the options for the information presented. 44.Bl -tag -width indent 45.It Xo 46.Bk -words 47.Nm 48.Op Fl AaLnSTWx 49.Op Fl f Ar protocol_family | Fl p Ar protocol 50.Op Fl M Ar core 51.Op Fl N Ar system 52.Ek 53.Xc 54Display a list of active sockets 55(protocol control blocks) 56for each network protocol, 57for a particular 58.Ar protocol_family , 59or for a single 60.Ar protocol . 61If 62.Fl A 63is also present, 64show the address of a protocol control block (PCB) 65associated with a socket; used for debugging. 66If 67.Fl a 68is also present, 69show the state of all sockets; 70normally sockets used by server processes are not shown. 71If 72.Fl L 73is also present, 74show the size of the various listen queues. 75The first count shows the number of unaccepted connections, 76the second count shows the amount of unaccepted incomplete connections, 77and the third count is the maximum number of queued connections. 78If 79.Fl S 80is also present, 81show network addresses as numbers (as with 82.Fl n ) 83but show ports symbolically. 84If 85.Fl x 86is present, display socket buffer and tcp timer statistics for each internet socket. 87When 88.Fl T 89is present, display information from the TCP control block, including 90retransmits, out-of-order packets received, and zero-sized windows advertised. 91.It Xo 92.Bk -words 93.Nm 94.Fl i | I Ar interface 95.Op Fl abdhnW 96.Op Fl f Ar address_family 97.Op Fl M Ar core 98.Op Fl N Ar system 99.Ek 100.Xc 101Show the state of all network interfaces or a single 102.Ar interface 103which have been auto-configured 104(interfaces statically configured into a system, but not 105located at boot time are not shown). 106An asterisk 107.Pq Dq Li * 108after an interface name indicates that the interface is 109.Dq down . 110If 111.Fl a 112is also present, multicast addresses currently in use are shown 113for each Ethernet interface and for each IP interface address. 114Multicast addresses are shown on separate lines following the interface 115address with which they are associated. 116If 117.Fl b 118is also present, show the number of bytes in and out. 119If 120.Fl d 121is also present, show the number of dropped packets. 122If 123.Fl h 124is also present, print all counters in human readable form. 125If 126.Fl W 127is also present, print interface names using a wider field size. 128.It Xo 129.Bk -words 130.Nm 131.Fl w Ar wait 132.Op Fl I Ar interface 133.Op Fl d 134.Op Fl M Ar core 135.Op Fl N Ar system 136.Op Fl q Ar howmany 137.Ek 138.Xc 139At intervals of 140.Ar wait 141seconds, 142display the information regarding packet 143traffic on all configured network interfaces 144or a single 145.Ar interface . 146If 147.Fl q 148is also present, exit after 149.Ar howmany 150outputs. 151If 152.Fl d 153is also present, show the number of dropped packets. 154.It Xo 155.Bk -words 156.Nm 157.Fl s Op Fl s 158.Op Fl z 159.Op Fl f Ar protocol_family | Fl p Ar protocol 160.Op Fl M Ar core 161.Op Fl N Ar system 162.Ek 163.Xc 164Display system-wide statistics for each network protocol, 165for a particular 166.Ar protocol_family , 167or for a single 168.Ar protocol . 169If 170.Fl s 171is repeated, counters with a value of zero are suppressed. 172If 173.Fl z 174is also present, reset statistic counters after displaying them. 175.It Xo 176.Bk -words 177.Nm 178.Fl i | I Ar interface Fl s 179.Op Fl f Ar protocol_family | Fl p Ar protocol 180.Op Fl M Ar core 181.Op Fl N Ar system 182.Ek 183.Xc 184Display per-interface statistics for each network protocol, 185for a particular 186.Ar protocol_family , 187or for a single 188.Ar protocol . 189.It Xo 190.Bk -words 191.Nm 192.Fl m 193.Op Fl M Ar core 194.Op Fl N Ar system 195.Ek 196.Xc 197Show statistics recorded by the memory management routines 198.Pq Xr mbuf 9 . 199The network manages a private pool of memory buffers. 200.It Xo 201.Bk -words 202.Nm 203.Fl B 204.Op Fl z 205.Op Fl I Ar interface 206.Ek 207.Xc 208Show statistics about 209.Xr bpf 4 210peers. 211This includes information like 212how many packets have been matched, dropped and received by the 213bpf device, also information about current buffer sizes and device 214states. 215.It Xo 216.Bk -words 217.Nm 218.Fl r 219.Op Fl AanW 220.Op Fl f Ar address_family 221.Op Fl M Ar core 222.Op Fl N Ar system 223.Ek 224.Xc 225Display the contents of all routing tables, 226or a routing table for a particular 227.Ar address_family . 228If 229.Fl A 230is also present, 231show the contents of the internal Patricia tree 232structures; used for debugging. 233If 234.Fl a 235is also present, 236show protocol-cloned routes 237(routes generated by an 238.Dv RTF_PRCLONING 239parent route); 240normally these routes are not shown. 241When 242.Fl W 243is also present, 244show the path MTU 245for each route, 246and print interface 247names with a wider 248field size. 249.It Xo 250.Bk -words 251.Nm 252.Fl rs 253.Op Fl s 254.Op Fl M Ar core 255.Op Fl N Ar system 256.Ek 257.Xc 258Display routing statistics. 259If 260.Fl s 261is repeated, counters with a value of zero are suppressed. 262.It Xo 263.Bk -words 264.Nm 265.Fl g 266.Op Fl W 267.Op Fl f Ar address_family 268.Op Fl M Ar core 269.Op Fl N Ar system 270.Ek 271.Xc 272Display the contents of the multicast virtual interface tables, 273and multicast forwarding caches. 274Entries in these tables will appear only when the kernel is 275actively forwarding multicast sessions. 276This option is applicable only to the 277.Cm inet 278and 279.Cm inet6 280address families. 281.It Xo 282.Bk -words 283.Nm 284.Fl gs 285.Op Fl s 286.Op Fl f Ar address_family 287.Op Fl M Ar core 288.Op Fl N Ar system 289.Ek 290.Xc 291Show multicast routing statistics. 292If 293.Fl s 294is repeated, counters with a value of zero are suppressed. 295.It Xo 296.Bk -words 297.Nm 298.Fl Q 299.Ek 300.Xc 301Show 302.Xr netisr 9 303statistics. 304The flags field shows available ISR handlers: 305.Bl -column ".Li W" ".Dv NETISR_SNP_FLAGS_DRAINEDCPU" 306.It Li C Ta Dv NETISR_SNP_FLAGS_M2CPUID Ta "Able to map mbuf to cpu id" 307.It Li D Ta Dv NETISR_SNP_FLAGS_DRAINEDCPU Ta "Has queue drain handler" 308.It Li F Ta Dv NETISR_SNP_FLAGS_M2FLOW Ta "Able to map mbuf to flow id" 309.El 310.El 311.Pp 312Some options have the general meaning: 313.Bl -tag -width flag 314.It Fl f Ar address_family , Fl p Ar protocol 315Limit display to those records 316of the specified 317.Ar address_family 318or a single 319.Ar protocol . 320The following address families and protocols are recognized: 321.Pp 322.Bl -tag -width ".Cm netgraph , ng Pq Dv AF_NETGRAPH" -compact 323.It Em Family 324.Em Protocols 325.It Cm inet Pq Dv AF_INET 326.Cm divert , icmp , igmp , ip , ipsec , pim, sctp , tcp , udp 327.It Cm inet6 Pq Dv AF_INET6 328.Cm icmp6 , ip6 , ipsec6 , rip6 , tcp , udp 329.It Cm pfkey Pq Dv PF_KEY 330.Cm pfkey 331.It Cm atalk Pq Dv AF_APPLETALK 332.Cm ddp 333.It Cm netgraph , ng Pq Dv AF_NETGRAPH 334.Cm ctrl , data 335.It Cm ipx Pq Dv AF_IPX 336.Cm ipx , spx 337.\".It Cm ns Pq Dv AF_NS 338.\".Cm idp , ns_err , spp 339.\".It Cm iso Pq Dv AF_ISO 340.\".Cm clnp , cltp , esis , tp 341.It Cm unix Pq Dv AF_UNIX 342.It Cm link Pq Dv AF_LINK 343.El 344.Pp 345The program will complain if 346.Ar protocol 347is unknown or if there is no statistics routine for it. 348.It Fl M 349Extract values associated with the name list from the specified core 350instead of the default 351.Pa /dev/kmem . 352.It Fl N 353Extract the name list from the specified system instead of the default, 354which is the kernel image the system has booted from. 355.It Fl n 356Show network addresses and ports as numbers. 357Normally 358.Nm 359attempts to resolve addresses and ports, 360and display them symbolically. 361.It Fl W 362In certain displays, avoid truncating addresses even if this causes 363some fields to overflow. 364.El 365.Pp 366The default display, for active sockets, shows the local 367and remote addresses, send and receive queue sizes (in bytes), protocol, 368and the internal state of the protocol. 369Address formats are of the form 370.Dq host.port 371or 372.Dq network.port 373if a socket's address specifies a network but no specific host address. 374When known, the host and network addresses are displayed symbolically 375according to the databases 376.Xr hosts 5 377and 378.Xr networks 5 , 379respectively. 380If a symbolic name for an address is unknown, or if 381the 382.Fl n 383option is specified, the address is printed numerically, according 384to the address family. 385For more information regarding 386the Internet IPv4 387.Dq dot format , 388refer to 389.Xr inet 3 . 390Unspecified, 391or 392.Dq wildcard , 393addresses and ports appear as 394.Dq Li * . 395.Pp 396The interface display provides a table of cumulative 397statistics regarding packets transferred, errors, and collisions. 398The network addresses of the interface 399and the maximum transmission unit 400.Pq Dq mtu 401are also displayed. 402.Pp 403The routing table display indicates the available routes and their status. 404Each route consists of a destination host or network, and a gateway to use 405in forwarding packets. 406The flags field shows a collection of information about the route stored 407as binary choices. 408The individual flags are discussed in more detail in the 409.Xr route 8 410and 411.Xr route 4 412manual pages. 413The mapping between letters and flags is: 414.Bl -column ".Li W" ".Dv RTF_WASCLONED" 415.It Li 1 Ta Dv RTF_PROTO1 Ta "Protocol specific routing flag #1" 416.It Li 2 Ta Dv RTF_PROTO2 Ta "Protocol specific routing flag #2" 417.It Li 3 Ta Dv RTF_PROTO3 Ta "Protocol specific routing flag #3" 418.It Li B Ta Dv RTF_BLACKHOLE Ta "Just discard pkts (during updates)" 419.It Li b Ta Dv RTF_BROADCAST Ta "The route represents a broadcast address" 420.It Li C Ta Dv RTF_CLONING Ta "Generate new routes on use" 421.It Li c Ta Dv RTF_PRCLONING Ta "Protocol-specified generate new routes on use" 422.It Li D Ta Dv RTF_DYNAMIC Ta "Created dynamically (by redirect)" 423.It Li G Ta Dv RTF_GATEWAY Ta "Destination requires forwarding by intermediary" 424.It Li H Ta Dv RTF_HOST Ta "Host entry (net otherwise)" 425.It Li L Ta Dv RTF_LLINFO Ta "Valid protocol to link address translation" 426.It Li M Ta Dv RTF_MODIFIED Ta "Modified dynamically (by redirect)" 427.It Li R Ta Dv RTF_REJECT Ta "Host or net unreachable" 428.It Li S Ta Dv RTF_STATIC Ta "Manually added" 429.It Li U Ta Dv RTF_UP Ta "Route usable" 430.It Li W Ta Dv RTF_WASCLONED Ta "Route was generated as a result of cloning" 431.It Li X Ta Dv RTF_XRESOLVE Ta "External daemon translates proto to link address" 432.El 433.Pp 434Direct routes are created for each 435interface attached to the local host; 436the gateway field for such entries shows the address of the outgoing interface. 437The refcnt field gives the 438current number of active uses of the route. 439Connection oriented 440protocols normally hold on to a single route for the duration of 441a connection while connectionless protocols obtain a route while sending 442to the same destination. 443The use field provides a count of the number of packets 444sent using that route. 445The interface entry indicates the network interface utilized for the route. 446.Pp 447When 448.Nm 449is invoked with the 450.Fl w 451option and a 452.Ar wait 453interval argument, it displays a running count of statistics related to 454network interfaces. 455An obsolescent version of this option used a numeric parameter 456with no option, and is currently supported for backward compatibility. 457By default, this display summarizes information for all interfaces. 458Information for a specific interface may be displayed with the 459.Fl I 460option. 461.Pp 462The 463.Xr bpf 4 464flags displayed when 465.Nm 466is invoked with the 467.Fl B 468option represent the underlying parameters of the bpf peer. 469Each flag is 470represented as a single lower case letter. 471The mapping between the letters and flags in order of appearance are: 472.Bl -column ".Li i" 473.It Li p Ta Set if listening promiscuously 474.It Li i Ta Dv BIOCIMMEDIATE No has been set on the device 475.It Li f Ta Dv BIOCGHDRCMPLT No status: source link addresses are being 476filled automatically 477.It Li s Ta Dv BIOCGSEESENT No status: see packets originating locally and 478remotely on the interface. 479.It Li a Ta Packet reception generates a signal 480.It Li l Ta Dv BIOCLOCK No status: descriptor has been locked 481.El 482.Pp 483For more information about these flags, please refer to 484.Xr bpf 4 . 485.Pp 486The 487.Fl x 488flag causes 489.Nm 490to output all the information recorded about data 491stored in the socket buffers. 492The fields are: 493.Bl -column ".Li R-MBUF" 494.It Li R-MBUF Ta Number of mbufs in the receive queue. 495.It Li S-MBUF Ta Number of mbufs in the send queue. 496.It Li R-CLUS Ta Number of clusters, of any type, in the receive 497queue. 498.It Li S-CLUS Ta Number of clusters, of any type, in the send queue. 499.It Li R-HIWA Ta Receive buffer high water mark, in bytes. 500.It Li S-HIWA Ta Send buffer high water mark, in bytes. 501.It Li R-LOWA Ta Receive buffer low water mark, in bytes. 502.It Li S-LOWA Ta Send buffer low water mark, in bytes. 503.It Li R-BCNT Ta Receive buffer byte count. 504.It Li S-BCNT Ta Send buffer byte count. 505.It Li R-BMAX Ta Maximum bytes that can be used in the receive buffer. 506.It Li S-BMAX Ta Maximum bytes that can be used in the send buffer. 507.El 508.Sh SEE ALSO 509.Xr fstat 1 , 510.Xr nfsstat 1 , 511.Xr procstat 1 , 512.Xr ps 1 , 513.Xr sockstat 1 , 514.Xr bpf 4 , 515.Xr inet 4 , 516.Xr route 4 , 517.Xr unix 4 , 518.Xr hosts 5 , 519.Xr networks 5 , 520.Xr protocols 5 , 521.Xr services 5 , 522.Xr iostat 8 , 523.Xr route 8 , 524.Xr trpt 8 , 525.Xr vmstat 8 , 526.Xr mbuf 9 527.Sh HISTORY 528The 529.Nm 530command appeared in 531.Bx 4.2 . 532.Pp 533IPv6 support was added by WIDE/KAME project. 534.Sh BUGS 535The notion of errors is ill-defined. 536