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