1What: /sys/class/net/<iface>/name_assign_type 2Date: July 2014 3KernelVersion: 3.17 4Contact: netdev@vger.kernel.org 5Description: 6 Indicates the name assignment type. Possible values are: 7 8 == ========================================================== 9 1 enumerated by the kernel, possibly in an unpredictable way 10 2 predictably named by the kernel 11 3 named by userspace 12 4 renamed 13 == ========================================================== 14 15What: /sys/class/net/<iface>/addr_assign_type 16Date: July 2010 17KernelVersion: 3.2 18Contact: netdev@vger.kernel.org 19Description: 20 Indicates the address assignment type. Possible values are: 21 22 == ============================= 23 0 permanent address 24 1 randomly generated 25 2 stolen from another device 26 3 set using dev_set_mac_address 27 == ============================= 28 29What: /sys/class/net/<iface>/addr_len 30Date: April 2005 31KernelVersion: 2.6.12 32Contact: netdev@vger.kernel.org 33Description: 34 Indicates the hardware address size in bytes. 35 Values vary based on the lower-level protocol used by the 36 interface (Ethernet, FDDI, ATM, IEEE 802.15.4...). See 37 include/uapi/linux/if_*.h for actual values. 38 39What: /sys/class/net/<iface>/address 40Date: April 2005 41KernelVersion: 2.6.12 42Contact: netdev@vger.kernel.org 43Description: 44 Hardware address currently assigned to this interface. 45 Format is a string, e.g: 00:11:22:33:44:55 for an Ethernet MAC 46 address. 47 48What: /sys/class/net/<bridge iface>/bridge/group_fwd_mask 49Date: January 2012 50KernelVersion: 3.2 51Contact: netdev@vger.kernel.org 52Description: 53 Bitmask to allow forwarding of link local frames with address 54 01-80-C2-00-00-0X on a bridge device. Only values that set bits 55 not matching BR_GROUPFWD_RESTRICTED in net/bridge/br_private.h 56 allowed. 57 Default value 0 does not forward any link local frames. 58 59 Restricted bits: 60 61 == ======================================================== 62 0 01-80-C2-00-00-00 Bridge Group Address used for STP 63 1 01-80-C2-00-00-01 (MAC Control) 802.3 used for MAC PAUSE 64 2 01-80-C2-00-00-02 (Link Aggregation) 802.3ad 65 == ======================================================== 66 67 Any values not setting these bits can be used. Take special 68 care when forwarding control frames e.g. 802.1X-PAE or LLDP. 69 70What: /sys/class/net/<iface>/broadcast 71Date: April 2005 72KernelVersion: 2.6.12 73Contact: netdev@vger.kernel.org 74Description: 75 Hardware broadcast address for this interface. Format is a 76 string, e.g: ff:ff:ff:ff:ff:ff for an Ethernet broadcast MAC 77 address. 78 79What: /sys/class/net/<iface>/carrier 80Date: April 2005 81KernelVersion: 2.6.12 82Contact: netdev@vger.kernel.org 83Description: 84 Indicates the current physical link state of the interface. 85 Posssible values are: 86 87 == ===================== 88 0 physical link is down 89 1 physical link is up 90 == ===================== 91 92 Note: some special devices, e.g: bonding and team drivers will 93 allow this attribute to be written to force a link state for 94 operating correctly and designating another fallback interface. 95 96What: /sys/class/net/<iface>/dev_id 97Date: April 2008 98KernelVersion: 2.6.26 99Contact: netdev@vger.kernel.org 100Description: 101 Indicates the device unique identifier. Format is an hexadecimal 102 value. This is used to disambiguate interfaces which might be 103 stacked (e.g: VLAN interfaces) but still have the same MAC 104 address as their parent device. 105 106What: /sys/class/net/<iface>/dev_port 107Date: February 2014 108KernelVersion: 3.15 109Contact: netdev@vger.kernel.org 110Description: 111 Indicates the port number of this network device, formatted 112 as a decimal value. Some NICs have multiple independent ports 113 on the same PCI bus, device and function. This attribute allows 114 userspace to distinguish the respective interfaces. 115 116 Note: some device drivers started to use 'dev_id' for this 117 purpose since long before 3.15 and have not adopted the new 118 attribute ever since. To query the port number, some tools look 119 exclusively at 'dev_port', while others only consult 'dev_id'. 120 If a network device has multiple client adapter ports as 121 described in the previous paragraph and does not set this 122 attribute to its port number, it's a kernel bug. 123 124What: /sys/class/net/<iface>/dormant 125Date: March 2006 126KernelVersion: 2.6.17 127Contact: netdev@vger.kernel.org 128Description: 129 Indicates whether the interface is in dormant state. Possible 130 values are: 131 0: interface is not dormant 132 1: interface is dormant 133 134 This attribute can be used by supplicant software to signal that 135 the device is not usable unless some supplicant-based 136 authentication is performed (e.g: 802.1x). 'link_mode' attribute 137 will also reflect the dormant state. 138 139What: /sys/class/net/<iface>/testing 140Date: April 2002 141KernelVersion: 5.8 142Contact: netdev@vger.kernel.org 143Description: 144 Indicates whether the interface is under test. Possible 145 values are: 146 147 == ============================= 148 0 interface is not being tested 149 1 interface is being tested 150 == ============================= 151 152 When an interface is under test, it cannot be expected 153 to pass packets as normal. 154 155What: /sys/class/net/<iface>/duplex 156Date: October 2009 157KernelVersion: 2.6.33 158Contact: netdev@vger.kernel.org 159Description: 160 Indicates the interface latest or current duplex value. Possible 161 values are: 162 163 ==== =========== 164 half half duplex 165 full full duplex 166 ==== =========== 167 168 Note: This attribute is only valid for interfaces that implement 169 the ethtool get_link_ksettings method (mostly Ethernet). 170 171What: /sys/class/net/<iface>/flags 172Date: April 2005 173KernelVersion: 2.6.12 174Contact: netdev@vger.kernel.org 175Description: 176 Indicates the interface flags as a bitmask in hexadecimal. See 177 include/uapi/linux/if.h for a list of all possible values and 178 the flags semantics. 179 180What: /sys/class/net/<iface>/ifalias 181Date: September 2008 182KernelVersion: 2.6.28 183Contact: netdev@vger.kernel.org 184Description: 185 Indicates/stores an interface alias name as a string. This can 186 be used for system management purposes. 187 188What: /sys/class/net/<iface>/ifindex 189Date: April 2005 190KernelVersion: 2.6.12 191Contact: netdev@vger.kernel.org 192Description: 193 Indicates the system-wide interface unique index identifier as a 194 decimal number. This attribute is used for mapping an interface 195 identifier to an interface name. It is used throughout the 196 networking stack for specifying the interface specific 197 requests/events. 198 199What: /sys/class/net/<iface>/iflink 200Date: April 2005 201KernelVersion: 2.6.12 202Contact: netdev@vger.kernel.org 203Description: 204 Indicates the system-wide interface unique index identifier a 205 the interface is linked to. Format is decimal. This attribute is 206 used to resolve interfaces chaining, linking and stacking. 207 Physical interfaces have the same 'ifindex' and 'iflink' values. 208 209What: /sys/class/net/<iface>/link_mode 210Date: March 2006 211KernelVersion: 2.6.17 212Contact: netdev@vger.kernel.org 213Description: 214 Indicates the interface link mode, as a decimal number. This 215 attribute should be used in conjunction with 'dormant' attribute 216 to determine the interface usability. Possible values: 217 218 == ================= 219 0 default link mode 220 1 dormant link mode 221 == ================= 222 223What: /sys/class/net/<iface>/mtu 224Date: April 2005 225KernelVersion: 2.6.12 226Contact: netdev@vger.kernel.org 227Description: 228 Indicates the interface currently configured MTU value, in 229 bytes, and in decimal format. Specific values depends on the 230 lower-level interface protocol used. Ethernet devices will show 231 a 'mtu' attribute value of 1500 unless changed. 232 233What: /sys/class/net/<iface>/netdev_group 234Date: January 2011 235KernelVersion: 2.6.39 236Contact: netdev@vger.kernel.org 237Description: 238 Indicates the interface network device group, as a decimal 239 integer. Default value is 0 which corresponds to the initial 240 network devices group. The group can be changed to affect 241 routing decisions (see: net/ipv4/fib_rules and 242 net/ipv6/fib6_rules.c). 243 244What: /sys/class/net/<iface>/operstate 245Date: March 2006 246KernelVersion: 2.6.17 247Contact: netdev@vger.kernel.org 248Description: 249 Indicates the interface RFC2863 operational state as a string. 250 251 Possible values are: 252 253 "unknown", "notpresent", "down", "lowerlayerdown", "testing", 254 "dormant", "up". 255 256What: /sys/class/net/<iface>/phys_port_id 257Date: July 2013 258KernelVersion: 3.12 259Contact: netdev@vger.kernel.org 260Description: 261 Indicates the interface unique physical port identifier within 262 the NIC, as a string. 263 264What: /sys/class/net/<iface>/phys_port_name 265Date: March 2015 266KernelVersion: 4.0 267Contact: netdev@vger.kernel.org 268Description: 269 Indicates the interface physical port name within the NIC, 270 as a string. 271 272What: /sys/class/net/<iface>/speed 273Date: October 2009 274KernelVersion: 2.6.33 275Contact: netdev@vger.kernel.org 276Description: 277 Indicates the interface latest or current speed value. Value is 278 an integer representing the link speed in Mbits/sec. 279 280 Note: this attribute is only valid for interfaces that implement 281 the ethtool get_link_ksettings method (mostly Ethernet). 282 283What: /sys/class/net/<iface>/tx_queue_len 284Date: April 2005 285KernelVersion: 2.6.12 286Contact: netdev@vger.kernel.org 287Description: 288 Indicates the interface transmit queue len in number of packets, 289 as an integer value. Value depend on the type of interface, 290 Ethernet network adapters have a default value of 1000 unless 291 configured otherwise 292 293What: /sys/class/net/<iface>/type 294Date: April 2005 295KernelVersion: 2.6.12 296Contact: netdev@vger.kernel.org 297Description: 298 Indicates the interface protocol type as a decimal value. See 299 include/uapi/linux/if_arp.h for all possible values. 300 301What: /sys/class/net/<iface>/phys_switch_id 302Date: November 2014 303KernelVersion: 3.19 304Contact: netdev@vger.kernel.org 305Description: 306 Indicates the unique physical switch identifier of a switch this 307 port belongs to, as a string. 308 309What: /sys/class/net/<iface>/phydev 310Date: May 2017 311KernelVersion: 4.13 312Contact: netdev@vger.kernel.org 313Description: 314 Symbolic link to the PHY device this network device is attached 315 to. 316 317What: /sys/class/net/<iface>/carrier_changes 318Date: Mar 2014 319KernelVersion: 3.15 320Contact: netdev@vger.kernel.org 321Description: 322 32-bit unsigned integer counting the number of times the link has 323 seen a change from UP to DOWN and vice versa 324 325What: /sys/class/net/<iface>/carrier_up_count 326Date: Jan 2018 327KernelVersion: 4.16 328Contact: netdev@vger.kernel.org 329Description: 330 32-bit unsigned integer counting the number of times the link has 331 been up 332 333What: /sys/class/net/<iface>/carrier_down_count 334Date: Jan 2018 335KernelVersion: 4.16 336Contact: netdev@vger.kernel.org 337Description: 338 32-bit unsigned integer counting the number of times the link has 339 been down 340