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/clas/net/<iface>/duplex 128Date: October 2009 129KernelVersion: 2.6.33 130Contact: netdev@vger.kernel.org 131Description: 132 Indicates the interface latest or current duplex value. Possible 133 values are: 134 half: half duplex 135 full: full duplex 136 137 Note: This attribute is only valid for interfaces that implement 138 the ethtool get_link_ksettings method (mostly Ethernet). 139 140What: /sys/class/net/<iface>/flags 141Date: April 2005 142KernelVersion: 2.6.12 143Contact: netdev@vger.kernel.org 144Description: 145 Indicates the interface flags as a bitmask in hexadecimal. See 146 include/uapi/linux/if.h for a list of all possible values and 147 the flags semantics. 148 149What: /sys/class/net/<iface>/ifalias 150Date: September 2008 151KernelVersion: 2.6.28 152Contact: netdev@vger.kernel.org 153Description: 154 Indicates/stores an interface alias name as a string. This can 155 be used for system management purposes. 156 157What: /sys/class/net/<iface>/ifindex 158Date: April 2005 159KernelVersion: 2.6.12 160Contact: netdev@vger.kernel.org 161Description: 162 Indicates the system-wide interface unique index identifier as a 163 decimal number. This attribute is used for mapping an interface 164 identifier to an interface name. It is used throughout the 165 networking stack for specifying the interface specific 166 requests/events. 167 168What: /sys/class/net/<iface>/iflink 169Date: April 2005 170KernelVersion: 2.6.12 171Contact: netdev@vger.kernel.org 172Description: 173 Indicates the system-wide interface unique index identifier a 174 the interface is linked to. Format is decimal. This attribute is 175 used to resolve interfaces chaining, linking and stacking. 176 Physical interfaces have the same 'ifindex' and 'iflink' values. 177 178What: /sys/class/net/<iface>/link_mode 179Date: March 2006 180KernelVersion: 2.6.17 181Contact: netdev@vger.kernel.org 182Description: 183 Indicates the interface link mode, as a decimal number. This 184 attribute should be used in conjunction with 'dormant' attribute 185 to determine the interface usability. Possible values: 186 0: default link mode 187 1: dormant link mode 188 189What: /sys/class/net/<iface>/mtu 190Date: April 2005 191KernelVersion: 2.6.12 192Contact: netdev@vger.kernel.org 193Description: 194 Indicates the interface currently configured MTU value, in 195 bytes, and in decimal format. Specific values depends on the 196 lower-level interface protocol used. Ethernet devices will show 197 a 'mtu' attribute value of 1500 unless changed. 198 199What: /sys/class/net/<iface>/netdev_group 200Date: January 2011 201KernelVersion: 2.6.39 202Contact: netdev@vger.kernel.org 203Description: 204 Indicates the interface network device group, as a decimal 205 integer. Default value is 0 which corresponds to the initial 206 network devices group. The group can be changed to affect 207 routing decisions (see: net/ipv4/fib_rules and 208 net/ipv6/fib6_rules.c). 209 210What: /sys/class/net/<iface>/operstate 211Date: March 2006 212KernelVersion: 2.6.17 213Contact: netdev@vger.kernel.org 214Description: 215 Indicates the interface RFC2863 operational state as a string. 216 Possible values are: 217 "unknown", "notpresent", "down", "lowerlayerdown", "testing", 218 "dormant", "up". 219 220What: /sys/class/net/<iface>/phys_port_id 221Date: July 2013 222KernelVersion: 3.12 223Contact: netdev@vger.kernel.org 224Description: 225 Indicates the interface unique physical port identifier within 226 the NIC, as a string. 227 228What: /sys/class/net/<iface>/phys_port_name 229Date: March 2015 230KernelVersion: 4.0 231Contact: netdev@vger.kernel.org 232Description: 233 Indicates the interface physical port name within the NIC, 234 as a string. 235 236What: /sys/class/net/<iface>/speed 237Date: October 2009 238KernelVersion: 2.6.33 239Contact: netdev@vger.kernel.org 240Description: 241 Indicates the interface latest or current speed value. Value is 242 an integer representing the link speed in Mbits/sec. 243 244 Note: this attribute is only valid for interfaces that implement 245 the ethtool get_link_ksettings method (mostly Ethernet). 246 247What: /sys/class/net/<iface>/tx_queue_len 248Date: April 2005 249KernelVersion: 2.6.12 250Contact: netdev@vger.kernel.org 251Description: 252 Indicates the interface transmit queue len in number of packets, 253 as an integer value. Value depend on the type of interface, 254 Ethernet network adapters have a default value of 1000 unless 255 configured otherwise 256 257What: /sys/class/net/<iface>/type 258Date: April 2005 259KernelVersion: 2.6.12 260Contact: netdev@vger.kernel.org 261Description: 262 Indicates the interface protocol type as a decimal value. See 263 include/uapi/linux/if_arp.h for all possible values. 264 265What: /sys/class/net/<iface>/phys_switch_id 266Date: November 2014 267KernelVersion: 3.19 268Contact: netdev@vger.kernel.org 269Description: 270 Indicates the unique physical switch identifier of a switch this 271 port belongs to, as a string. 272 273What: /sys/class/net/<iface>/phydev 274Date: May 2017 275KernelVersion: 4.13 276Contact: netdev@vger.kernel.org 277Description: 278 Symbolic link to the PHY device this network device is attached 279 to. 280 281What: /sys/class/net/<iface>/carrier_changes 282Date: Mar 2014 283KernelVersion: 3.15 284Contact: netdev@vger.kernel.org 285Description: 286 32-bit unsigned integer counting the number of times the link has 287 seen a change from UP to DOWN and vice versa 288 289What: /sys/class/net/<iface>/carrier_up_count 290Date: Jan 2018 291KernelVersion: 4.16 292Contact: netdev@vger.kernel.org 293Description: 294 32-bit unsigned integer counting the number of times the link has 295 been up 296 297What: /sys/class/net/<iface>/carrier_down_count 298Date: Jan 2018 299KernelVersion: 4.16 300Contact: netdev@vger.kernel.org 301Description: 302 32-bit unsigned integer counting the number of times the link has 303 been down 304