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Diffstat (limited to 'man5/proc_pid_net.5')
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diff --git a/man5/proc_pid_net.5 b/man5/proc_pid_net.5 new file mode 100644 index 0000000..590e87d --- /dev/null +++ b/man5/proc_pid_net.5 @@ -0,0 +1,298 @@ +.\" Copyright (C) 1994, 1995, Daniel Quinlan <quinlan@yggdrasil.com> +.\" Copyright (C) 2002-2008, 2017, Michael Kerrisk <mtk.manpages@gmail.com> +.\" Copyright (C) , Alan Cox <A.Cox@swansea.ac.uk> +.\" Copyright (C) 2023, Alejandro Colomar <alx@kernel.org> +.\" +.\" SPDX-License-Identifier: GPL-3.0-or-later +.\" +.TH proc_pid_net 5 2023-08-15 "Linux man-pages 6.7" +.SH NAME +/proc/pid/net/, /proc/net/ \- network layer information +.SH DESCRIPTION +.TP +.IR /proc/ pid /net/ " (since Linux 2.6.25)" +See the description of +.IR /proc/net . +.TP +.I /proc/net/ +This directory contains various files and subdirectories containing +information about the networking layer. +The files contain ASCII structures and are, +therefore, readable with +.BR cat (1). +However, the standard +.BR netstat (8) +suite provides much cleaner access to these files. +.IP +With the advent of network namespaces, +various information relating to the network stack is virtualized (see +.BR network_namespaces (7)). +Thus, since Linux 2.6.25, +.\" commit e9720acd728a46cb40daa52c99a979f7c4ff195c +.I /proc/net +is a symbolic link to the directory +.IR /proc/self/net , +which contains the same files and directories as listed below. +However, these files and directories now expose information +for the network namespace of which the process is a member. +.TP +.I /proc/net/arp +This holds an ASCII readable dump of the kernel ARP table used for +address resolutions. +It will show both dynamically learned and preprogrammed ARP entries. +The format is: +.IP +.in +4n +.EX +IP address HW type Flags HW address Mask Device +192.168.0.50 0x1 0x2 00:50:BF:25:68:F3 * eth0 +192.168.0.250 0x1 0xc 00:00:00:00:00:00 * eth0 +.EE +.in +.IP +Here "IP address" is the IPv4 address of the machine and the "HW type" +is the hardware type of the address from RFC\ 826. +The flags are the internal +flags of the ARP structure (as defined in +.IR /usr/include/linux/if_arp.h ) +and +the "HW address" is the data link layer mapping for that IP address if +it is known. +.TP +.I /proc/net/dev +The dev pseudo-file contains network device status information. +This gives +the number of received and sent packets, the number of errors and +collisions +and other basic statistics. +These are used by the +.BR ifconfig (8) +program to report device status. +The format is: +.IP +.EX +Inter\-| Receive | Transmit + face |bytes packets errs drop fifo frame compressed multicast|bytes packets errs drop fifo colls carrier compressed + lo: 2776770 11307 0 0 0 0 0 0 2776770 11307 0 0 0 0 0 0 + eth0: 1215645 2751 0 0 0 0 0 0 1782404 4324 0 0 0 427 0 0 + ppp0: 1622270 5552 1 0 0 0 0 0 354130 5669 0 0 0 0 0 0 + tap0: 7714 81 0 0 0 0 0 0 7714 81 0 0 0 0 0 0 +.EE +.\" .TP +.\" .I /proc/net/ipx +.\" No information. +.\" .TP +.\" .I /proc/net/ipx_route +.\" No information. +.TP +.I /proc/net/dev_mcast +Defined in +.IR /usr/src/linux/net/core/dev_mcast.c : +.IP +.in +4n +.EX +indx interface_name dmi_u dmi_g dmi_address +2 eth0 1 0 01005e000001 +3 eth1 1 0 01005e000001 +4 eth2 1 0 01005e000001 +.EE +.in +.TP +.I /proc/net/igmp +Internet Group Management Protocol. +Defined in +.IR /usr/src/linux/net/core/igmp.c . +.TP +.I /proc/net/rarp +This file uses the same format as the +.I arp +file and contains the current reverse mapping database used to provide +.BR rarp (8) +reverse address lookup services. +If RARP is not configured into the +kernel, +this file will not be present. +.TP +.I /proc/net/raw +Holds a dump of the RAW socket table. +Much of the information is not of +use +apart from debugging. +The "sl" value is the kernel hash slot for the +socket, +the "local_address" is the local address and protocol number pair. +\&"St" is +the internal status of the socket. +The "tx_queue" and "rx_queue" are the +outgoing and incoming data queue in terms of kernel memory usage. +The "tr", "tm\->when", and "rexmits" fields are not used by RAW. +The "uid" +field holds the effective UID of the creator of the socket. +.\" .TP +.\" .I /proc/net/route +.\" No information, but looks similar to +.\" .BR route (8). +.TP +.I /proc/net/snmp +This file holds the ASCII data needed for the IP, ICMP, TCP, and UDP +management +information bases for an SNMP agent. +.TP +.I /proc/net/tcp +Holds a dump of the TCP socket table. +Much of the information is not +of use apart from debugging. +The "sl" value is the kernel hash slot +for the socket, the "local_address" is the local address and port number pair. +The "rem_address" is the remote address and port number pair +(if connected). +\&"St" is the internal status of the socket. +The "tx_queue" and "rx_queue" are the +outgoing and incoming data queue in terms of kernel memory usage. +The "tr", "tm\->when", and "rexmits" fields hold internal information of +the kernel socket state and are useful only for debugging. +The "uid" +field holds the effective UID of the creator of the socket. +.TP +.I /proc/net/udp +Holds a dump of the UDP socket table. +Much of the information is not of +use apart from debugging. +The "sl" value is the kernel hash slot for the +socket, the "local_address" is the local address and port number pair. +The "rem_address" is the remote address and port number pair +(if connected). +"St" is the internal status of the socket. +The "tx_queue" and "rx_queue" are the outgoing and incoming data queue +in terms of kernel memory usage. +The "tr", "tm\->when", and "rexmits" fields +are not used by UDP. +The "uid" +field holds the effective UID of the creator of the socket. +The format is: +.IP +.EX +sl local_address rem_address st tx_queue rx_queue tr rexmits tm\->when uid + 1: 01642C89:0201 0C642C89:03FF 01 00000000:00000001 01:000071BA 00000000 0 + 1: 00000000:0801 00000000:0000 0A 00000000:00000000 00:00000000 6F000100 0 + 1: 00000000:0201 00000000:0000 0A 00000000:00000000 00:00000000 00000000 0 +.EE +.TP +.I /proc/net/unix +Lists the UNIX domain sockets present within the system and their +status. +The format is: +.IP +.EX +Num RefCount Protocol Flags Type St Inode Path + 0: 00000002 00000000 00000000 0001 03 42 + 1: 00000001 00000000 00010000 0001 01 1948 /dev/printer +.EE +.IP +The fields are as follows: +.RS +.TP 10 +.IR Num : +the kernel table slot number. +.TP +.IR RefCount : +the number of users of the socket. +.TP +.IR Protocol : +currently always 0. +.TP +.IR Flags : +the internal kernel flags holding the status of the socket. +.TP +.IR Type : +the socket type. +For +.B SOCK_STREAM +sockets, this is 0001; for +.B SOCK_DGRAM +sockets, it is 0002; and for +.B SOCK_SEQPACKET +sockets, it is 0005. +.TP +.IR St : +the internal state of the socket. +.TP +.IR Inode : +the inode number of the socket. +.TP +.IR Path : +the bound pathname (if any) of the socket. +Sockets in the abstract namespace are included in the list, +and are shown with a +.I Path +that commences with the character '@'. +.RE +.TP +.I /proc/net/netfilter/nfnetlink_queue +This file contains information about netfilter user-space queueing, if used. +Each line represents a queue. +Queues that have not been subscribed to +by user space are not shown. +.IP +.in +4n +.EX + 1 4207 0 2 65535 0 0 0 1 + (1) (2) (3)(4) (5) (6) (7) (8) +.EE +.in +.IP +The fields in each line are: +.RS 7 +.TP 5 +(1) +The ID of the queue. +This matches what is specified in the +.B \-\-queue\-num +or +.B \-\-queue\-balance +options to the +.BR iptables (8) +NFQUEUE target. +See +.BR iptables\-extensions (8) +for more information. +.TP +(2) +The netlink port ID subscribed to the queue. +.TP +(3) +The number of packets currently queued and waiting to be processed by +the application. +.TP +(4) +The copy mode of the queue. +It is either 1 (metadata only) or 2 +(also copy payload data to user space). +.TP +(5) +Copy range; that is, how many bytes of packet payload should be copied to +user space at most. +.TP +(6) +queue dropped. +Number of packets that had to be dropped by the kernel because +too many packets are already waiting for user space to send back the mandatory +accept/drop verdicts. +.TP +(7) +queue user dropped. +Number of packets that were dropped within the netlink +subsystem. +Such drops usually happen when the corresponding socket buffer is +full; that is, user space is not able to read messages fast enough. +.TP +(8) +sequence number. +Every queued packet is associated with a (32-bit) +monotonically increasing sequence number. +This shows the ID of the most recent packet queued. +.RE +.IP +The last number exists only for compatibility reasons and is always 1. +.SH SEE ALSO +.BR proc (5) |