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-*- nroff -*-
Copyright 1999 by David S. Miller. All Rights Reserved.
Portions Copyright 2001 Sun Microsystems
Portions Copyright 2007, 2009 Free Software Foundation, Inc.
This file may be copied under the terms of the GNU Public License.

There must be no text lines before .TH. Use '.' for vertical spacing.

.An - list of n alternative values as in "flav vanilla|strawberry"

\\\$1\|\\\$2\ .. \\\$1\ \\\$2\|\\\$3\ .. \\\$1\ \\\$2\|\\\$3\|\\\$4\ .. \\\$1\ \\\$2\|\\\$3\|\\\$4\|\\\$5\ ..
.Bn - same as above but framed by square brackets

[\\\$1\|\\\$2\] .. [\\\$1\ \\\$2\|\\\$3\] .. [\\\$1\ \\\$2\|\\\$3\|\\\$4\] .. [\\\$1\ \\\$2\|\\\$3\|\\\$4\|\\\$5\] ..
.BN - value with a numeric input as in "[value N]"

[\\\$1\ \N\] ..
.BM - same as above but has a mask field for format "[value N [m N]]"

[\\\$1\ \N\ [\m\ \N\]] ..
\(*MA - mac address


\(*PA - IP address


\(*WO - wol flags


\(*FL - flow type values


\(*HO - hash options


\(*SD - Self-diag test values


\(*NC - Network Classifier type values

..
Start URL.
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. ie \\n(mH \{\ . br . di . ev . . \" Has there been one or more input lines for the link text? . ie \\n(dn \{\ . do HTML-NS "<a href=""\\*(m1"">" . \" Yes, strip off final newline of diversion and emit it. . do chop URL-div . do URL-div \c . do HTML-NS </a> . \} . el \ . do HTML-NS "<a href=""\\*(m1"">\\*(m1</a>" \\$*\" . \} . el \ \\*(la\\*(m1\\*(ra\\$*\" . . hy \\n(HY .. .
ETHTOOL 8 "September 2019" "Ethtool version @VERSION@"
NAME
ethtool - query or control network driver and hardware settings .
SYNOPSIS
Do not adjust lines (i.e. left justification) and do not hyphenate.

ethtool devname

ethtool -h|--help

ethtool --version

ethtool -a|--show-pause devname

ethtool -A|--pause devname 2 autoneg on off 2 rx on off 2 tx on off

ethtool -c|--show-coalesce devname

ethtool -C|--coalesce devname 2 adaptive-rx on off 2 adaptive-tx on off N rx-usecs N rx-frames N rx-usecs-irq N rx-frames-irq N tx-usecs N tx-frames N tx-usecs-irq N tx-frames-irq N stats-block-usecs N pkt-rate-low N rx-usecs-low N rx-frames-low N tx-usecs-low N tx-frames-low N pkt-rate-high N rx-usecs-high N rx-frames-high N tx-usecs-high N tx-frames-high N sample-interval

ethtool -g|--show-ring devname

ethtool -G|--set-ring devname N rx N rx-mini N rx-jumbo N tx

ethtool -i|--driver devname

ethtool -d|--register-dump devname 2 raw on off 2 hex on off [ file name ]

ethtool -e|--eeprom-dump devname 2 raw on off N offset N length

ethtool -E|--change-eeprom devname N magic N offset N length N value

ethtool -k|--show-features|--show-offload devname

ethtool -K|--features|--offload devname feature .A1 on off ...

ethtool -p|--identify devname [ N ]

ethtool -P|--show-permaddr devname

ethtool -r|--negotiate devname

ethtool -S|--statistics devname

ethtool --phy-statistics devname

ethtool -t|--test devname [\*(SD]

ethtool -s devname N speed 2 duplex half full 4 port tp aui bnc mii fibre 3 mdix auto on off 2 autoneg on off N advertise N phyad 2 xcvr internal external [ wol \*(WO] [ sopass \*(MA] [ msglvl N | msglvl type .A1 on off ...]

ethtool -n|-u|--show-nfc|--show-ntuple devname [ rx-flow-hash \*(FL |

rule N ]

ethtool -N|-U|--config-nfc|--config-ntuple devname rx-flow-hash \*(FL \: \*(HO |

flow-type \*(NC [ src \*(MA [ m \*(MA]] [ dst \*(MA [ m \*(MA]] M proto [ src-ip \*(PA [ m \*(PA]] [ dst-ip \*(PA [ m \*(PA]] M tos M tclass M l4proto M src-port M dst-port M spi M l4data M vlan-etype M vlan M user-def [ dst-mac \*(MA [ m \*(MA]] N action N context N loc |

delete N

ethtool -w|--get-dump devname [ data filename ]

ethtool -W|--set-dump devname N

ethtool -T|--show-time-stamping devname

ethtool -x|--show-rxfh-indir|--show-rxfh devname

ethtool -X|--set-rxfh-indir|--rxfh devname [ hkey \*(MA:\...] [ start N ] [ equal N | weight W0 W1 ... | default ] [ hfunc FUNC ] [ context CTX | new ] [ delete ]

ethtool -f|--flash devname file [ N ]

ethtool -l|--show-channels devname

ethtool -L|--set-channels devname N rx N tx N other N combined

ethtool -m|--dump-module-eeprom|--module-info devname 2 raw on off 2 hex on off N offset N length

ethtool --show-priv-flags devname

ethtool --set-priv-flags devname flag .A1 on off ...

ethtool --show-eee devname

ethtool --set-eee devname 2 eee on off 2 tx-lpi on off N tx-timer N advertise

ethtool --set-phy-tunable devname [ downshift .A1 on off N count ] [ fast-link-down .A1 on off N msecs ] [ energy-detect-power-down .A1 on off N msecs ]

ethtool --get-phy-tunable devname [ downshift ] [ fast-link-down ] [ energy-detect-power-down ]

ethtool --reset devname N flags [ mgmt ] [ mgmt-shared ] [ irq ] [ irq-shared ] [ dma ] [ dma-shared ] [ filter ] [ filter-shared ] [ offload ] [ offload-shared ] [ mac ] [ mac-shared ] [ phy ] [ phy-shared ] [ ram ] [ ram-shared ] [ ap ] [ ap-shared ] [ dedicated ] [ all ]

ethtool --show-fec devname

ethtool --set-fec devname encoding auto | off | rs | baser [...]

ethtool -Q|--per-queue devname [ queue_mask %x ] sub_command ... . . Adjust lines (i.e. full justification) and hyphenate.

DESCRIPTION
ethtool is used to query and control network device driver and hardware settings, particularly for wired Ethernet devices. devname is the name of the network device on which ethtool should operate.
OPTIONS
ethtool with a single argument specifying the device name prints current settings of the specified device.

-h --help Shows a short help message.

--version Shows the ethtool version number.

-a --show-pause Queries the specified Ethernet device for pause parameter information.

-A --pause Changes the pause parameters of the specified Ethernet device.

.A2 autoneg on off Specifies whether pause autonegotiation should be enabled.

.A2 rx on off Specifies whether RX pause should be enabled.

.A2 tx on off Specifies whether TX pause should be enabled.

-c --show-coalesce Queries the specified network device for coalescing information.

-C --coalesce Changes the coalescing settings of the specified network device.

-g --show-ring Queries the specified network device for rx/tx ring parameter information.

-G --set-ring Changes the rx/tx ring parameters of the specified network device.

rx N Changes the number of ring entries for the Rx ring.

rx-mini N Changes the number of ring entries for the Rx Mini ring.

rx-jumbo N Changes the number of ring entries for the Rx Jumbo ring.

tx N Changes the number of ring entries for the Tx ring.

-i --driver Queries the specified network device for associated driver information.

-d --register-dump Retrieves and prints a register dump for the specified network device. The register format for some devices is known and decoded others are printed in hex. When raw is enabled, then ethtool dumps the raw register data to stdout. If file is specified, then use contents of previous raw register dump, rather than reading from the device.

-e --eeprom-dump Retrieves and prints an EEPROM dump for the specified network device. When raw is enabled, then it dumps the raw EEPROM data to stdout. The length and offset parameters allow dumping certain portions of the EEPROM. Default is to dump the entire EEPROM.

raw on|off

offset N

length N

-E --change-eeprom If value is specified, changes EEPROM byte for the specified network device. offset and value specify which byte and it's new value. If value is not specified, stdin is read and written to the EEPROM. The length and offset parameters allow writing to certain portions of the EEPROM. Because of the persistent nature of writing to the EEPROM, a device-specific magic key must be specified to prevent the accidental writing to the EEPROM.

-k --show-features --show-offload Queries the specified network device for the state of protocol offload and other features.

-K --features --offload Changes the offload parameters and other features of the specified network device. The following feature names are built-in and others may be defined by the kernel.

.A2 rx on off Specifies whether RX checksumming should be enabled.

.A2 tx on off Specifies whether TX checksumming should be enabled.

.A2 sg on off Specifies whether scatter-gather should be enabled.

.A2 tso on off Specifies whether TCP segmentation offload should be enabled.

.A2 ufo on off Specifies whether UDP fragmentation offload should be enabled

.A2 gso on off Specifies whether generic segmentation offload should be enabled

.A2 gro on off Specifies whether generic receive offload should be enabled

.A2 lro on off Specifies whether large receive offload should be enabled

.A2 rxvlan on off Specifies whether RX VLAN acceleration should be enabled

.A2 txvlan on off Specifies whether TX VLAN acceleration should be enabled

.A2 ntuple on off Specifies whether Rx ntuple filters and actions should be enabled

.A2 rxhash on off Specifies whether receive hashing offload should be enabled

-p --identify Initiates adapter-specific action intended to enable an operator to easily identify the adapter by sight. Typically this involves blinking one or more LEDs on the specific network port.

N Length of time to perform phys-id, in seconds.

-P --show-permaddr Queries the specified network device for permanent hardware address.

-r --negotiate Restarts auto-negotiation on the specified Ethernet device, if auto-negotiation is enabled.

-S --statistics Queries the specified network device for NIC- and driver-specific statistics.

--phy-statistics Queries the specified network device for PHY specific statistics.

-t --test Executes adapter selftest on the specified network device. Possible test modes are:

offline Perform full set of tests, possibly interrupting normal operation during the tests,

online Perform limited set of tests, not interrupting normal operation,

external_lb Perform full set of tests, as for offline, and additionally an external-loopback test.

-s --change Allows changing some or all settings of the specified network device. All following options only apply if -s was specified.

speed N Set speed in Mb/s. ethtool with just the device name as an argument will show you the supported device speeds.

.A2 duplex half full Sets full or half duplex mode.

.A4 port tp aui bnc mii fibre Selects device port.

.A3 mdix auto on off Selects MDI-X mode for port. May be used to override the automatic detection feature of most adapters. An argument of auto means automatic detection of MDI status, on forces MDI-X (crossover) mode, while off means MDI (straight through) mode. The driver should guarantee that this command takes effect immediately, and if necessary may reset the link to cause the change to take effect.

.A2 autoneg on off Specifies whether autonegotiation should be enabled. Autonegotiation is enabled by default, but in some network devices may have trouble with it, so you can disable it if really necessary.

advertise N Sets the speed and duplex advertised by autonegotiation. The argument is a hexadecimal value using one or a combination of the following values:

0x001 10baseT Half
0x002 10baseT Full
0x004 100baseT Half
0x008 100baseT Full
0x80000000000000000 100baseT1 Full
0x010 1000baseT Half (not supported by IEEE standards)
0x020 1000baseT Full
0x100000000000000000 1000baseT1 Full
0x20000 1000baseKX Full
0x20000000000 1000baseX Full
0x800000000000 2500baseT Full
0x8000 2500baseX Full (not supported by IEEE standards)
0x1000000000000 5000baseT Full
0x1000 10000baseT Full
0x40000 10000baseKX4 Full
0x80000 10000baseKR Full
0x100000 10000baseR_FEC
0x40000000000 10000baseCR Full
0x80000000000 10000baseSR Full
0x100000000000 10000baseLR Full
0x200000000000 10000baseLRM Full
0x400000000000 10000baseER Full
0x200000 20000baseMLD2 Full (not supported by IEEE standards)
0x400000 20000baseKR2 Full (not supported by IEEE standards)
0x80000000 25000baseCR Full
0x100000000 25000baseKR Full
0x200000000 25000baseSR Full
0x800000 40000baseKR4 Full
0x1000000 40000baseCR4 Full
0x2000000 40000baseSR4 Full
0x4000000 40000baseLR4 Full
0x400000000 50000baseCR2 Full
0x800000000 50000baseKR2 Full
0x10000000000 50000baseSR2 Full
0x10000000000000 50000baseKR Full
0x20000000000000 50000baseSR Full
0x40000000000000 50000baseCR Full
0x80000000000000 50000baseLR_ER_FR Full
0x100000000000000 50000baseDR Full
0x8000000 56000baseKR4 Full
0x10000000 56000baseCR4 Full
0x20000000 56000baseSR4 Full
0x40000000 56000baseLR4 Full
0x1000000000 100000baseKR4 Full
0x2000000000 100000baseSR4 Full
0x4000000000 100000baseCR4 Full
0x8000000000 100000baseLR4_ER4 Full
0x200000000000000 100000baseKR2 Full
0x400000000000000 100000baseSR2 Full
0x800000000000000 100000baseCR2 Full
0x1000000000000000 100000baseLR2_ER2_FR2 Full
0x2000000000000000 100000baseDR2 Full
0x4000000000000000 200000baseKR4 Full
0x8000000000000000 200000baseSR4 Full
0x10000000000000000 200000baseLR4_ER4_FR4 Full
0x20000000000000000 200000baseDR4 Full
0x40000000000000000 200000baseCR4 Full

phyad N PHY address.

.A2 xcvr internal external Selects transceiver type. Currently only internal and external can be specified, in the future further types might be added.

wol \*(WO Sets Wake-on-LAN options. Not all devices support this. The argument to this option is a string of characters specifying which options to enable.

p Wake on PHY activity
u Wake on unicast messages
m Wake on multicast messages
b Wake on broadcast messages
a Wake on ARP
g Wake on MagicPacket\[tm]
s Enable SecureOn\[tm] password for MagicPacket\[tm]
f Wake on filter(s)
d
Disable (wake on nothing). This option clears all previous options.

sopass \*(MA Sets the SecureOn\[tm] password. The argument to this option must be 6 bytes in Ethernet MAC hex format (\*(MA).

msglvl N

msglvl type .A1 on off ...

Sets the driver message type flags by name or number. type names the type of message to enable or disable; N specifies the new flags numerically. The defined type names and numbers are:

drv 0x0001 General driver status
probe 0x0002 Hardware probing
link 0x0004 Link state
timer 0x0008 Periodic status check
ifdown 0x0010 Interface being brought down
ifup 0x0020 Interface being brought up
rx_err 0x0040 Receive error
tx_err 0x0080 Transmit error
tx_queued 0x0100 Transmit queueing
intr 0x0200 Interrupt handling
tx_done 0x0400 Transmit completion
rx_status 0x0800 Receive completion
pktdata 0x1000 Packet contents
hw 0x2000 Hardware status
wol 0x4000 Wake-on-LAN status

The precise meanings of these type flags differ between drivers.

-n -u --show-nfc --show-ntuple Retrieves receive network flow classification options or rules.

rx-flow-hash \*(FL Retrieves the hash options for the specified flow type.

tcp4 TCP over IPv4
udp4 UDP over IPv4
ah4 IPSEC AH over IPv4
esp4 IPSEC ESP over IPv4
sctp4 SCTP over IPv4
tcp6 TCP over IPv6
udp6 UDP over IPv6
ah6 IPSEC AH over IPv6
esp6 IPSEC ESP over IPv6
sctp6 SCTP over IPv6

rule N Retrieves the RX classification rule with the given ID.

-N -U --config-nfc --config-ntuple Configures receive network flow classification options or rules.

rx-flow-hash \*(FL \: \*(HO Configures the hash options for the specified flow type.

m Hash on the Layer 2 destination address of the rx packet.
v Hash on the VLAN tag of the rx packet.
t Hash on the Layer 3 protocol field of the rx packet.
s Hash on the IP source address of the rx packet.
d Hash on the IP destination address of the rx packet.
f Hash on bytes 0 and 1 of the Layer 4 header of the rx packet.
n Hash on bytes 2 and 3 of the Layer 4 header of the rx packet.
r
Discard all packets of this flow type. When this option is set, all
other options are ignored.

flow-type \*(NC Inserts or updates a classification rule for the specified flow type.

ether Ethernet
ip4 Raw IPv4
tcp4 TCP over IPv4
udp4 UDP over IPv4
sctp4 SCTP over IPv4
ah4 IPSEC AH over IPv4
esp4 IPSEC ESP over IPv4
ip6 Raw IPv6
tcp6 TCP over IPv6
udp6 UDP over IPv6
sctp6 SCTP over IPv6
ah6 IPSEC AH over IPv6
esp6 IPSEC ESP over IPv6

For all fields that allow both a value and a mask to be specified, the mask may be specified immediately after the value using the m keyword, or separately using the field name keyword with -mask appended, e.g. src-mask.

src \*(MA [ m \*(MA] Includes the source MAC address, specified as 6 bytes in hexadecimal separated by colons, along with an optional mask. Valid only for flow-type ether.

dst \*(MA [ m \*(MA] Includes the destination MAC address, specified as 6 bytes in hexadecimal separated by colons, along with an optional mask. Valid only for flow-type ether.

proto N \ [\m N \]\ Includes the Ethernet protocol number (ethertype) and an optional mask. Valid only for flow-type ether.

src-ip \*(PA [ m \*(PA] Specify the source IP address of the incoming packet to match along with an optional mask. Valid for all IP based flow-types.

dst-ip \*(PA [ m \*(PA] Specify the destination IP address of the incoming packet to match along with an optional mask. Valid for all IP based flow-types.

tos N \ [\m N \]\ Specify the value of the Type of Service field in the incoming packet to match along with an optional mask. Applies to all IPv4 based flow-types.

tclass N \ [\m N \]\ Specify the value of the Traffic Class field in the incoming packet to match along with an optional mask. Applies to all IPv6 based flow-types.

l4proto N \ [\m N \]\ Includes the layer 4 protocol number and optional mask. Valid only for flow-types ip4 and ip6.

src-port N \ [\m N \]\ Specify the value of the source port field (applicable to TCP/UDP packets) in the incoming packet to match along with an optional mask. Valid for flow-types ip4, tcp4, udp4, and sctp4 and their IPv6 equivalents.

dst-port N \ [\m N \]\ Specify the value of the destination port field (applicable to TCP/UDP packets)in the incoming packet to match along with an optional mask. Valid for flow-types ip4, tcp4, udp4, and sctp4 and their IPv6 equivalents.

spi N \ [\m N \]\ Specify the value of the security parameter index field (applicable to AH/ESP packets)in the incoming packet to match along with an optional mask. Valid for flow-types ip4, ah4, and esp4 and their IPv6 equivalents.

l4data N \ [\m N \]\ Specify the value of the first 4 Bytes of Layer 4 in the incoming packet to match along with an optional mask. Valid for ip4 and ip6 flow-types.

vlan-etype N \ [\m N \]\ Includes the VLAN tag Ethertype and an optional mask.

vlan N \ [\m N \]\ Includes the VLAN tag and an optional mask.

user-def N \ [\m N \]\ Includes 64-bits of user-specific data and an optional mask.

dst-mac \*(MA [ m \*(MA] Includes the destination MAC address, specified as 6 bytes in hexadecimal separated by colons, along with an optional mask. Valid for all IP based flow-types.

action N Specifies the Rx queue to send packets to, or some other action.

-1 Drop the matched flow
-2 Use the matched flow as a Wake-on-LAN filter
0 or higher Rx queue to route the flow

context N Specifies the RSS context to spread packets over multiple queues; either 0 for the default RSS context, or a value returned by ethtool -X ... context new .

vf N Specifies the Virtual Function the filter applies to. Not compatible with action.

queue N Specifies the Rx queue to send packets to. Not compatible with action.

loc N Specify the location/ID to insert the rule. This will overwrite any rule present in that location and will not go through any of the rule ordering process.

delete N Deletes the RX classification rule with the given ID.

-w --get-dump Retrieves and prints firmware dump for the specified network device. By default, it prints out the dump flag, version and length of the dump data. When data is indicated, then ethtool fetches the dump data and directs it to a file.

-W --set-dump Sets the dump flag for the device.

-T --show-time-stamping Show the device's time stamping capabilities and associated PTP hardware clock.

-x --show-rxfh-indir --show-rxfh Retrieves the receive flow hash indirection table and/or RSS hash key.

-X --set-rxfh-indir --rxfh Configures the receive flow hash indirection table and/or RSS hash key.

hkey Sets RSS hash key of the specified network device. RSS hash key should be of device supported length. Hash key format must be in xx:yy:zz:aa:bb:cc format meaning both the nibbles of a byte should be mentioned even if a nibble is zero.

hfunc Sets RSS hash function of the specified network device. List of RSS hash functions which kernel supports is shown as a part of the --show-rxfh command output.

start N For the equal and weight options, sets the starting receive queue for spreading flows to N.

equal N Sets the receive flow hash indirection table to spread flows evenly between the first N receive queues.

weight W0 W1 ... Sets the receive flow hash indirection table to spread flows between receive queues according to the given weights. The sum of the weights must be non-zero and must not exceed the size of the indirection table.

default Sets the receive flow hash indirection table to its default value.

context CTX | new Specifies an RSS context to act on; either new to allocate a new RSS context, or CTX , a value returned by a previous ... context new .

delete Delete the specified RSS context. May only be used in conjunction with context and a non-zero CTX value.

-f --flash Write a firmware image to flash or other non-volatile memory on the device.

file Specifies the filename of the firmware image. The firmware must first be installed in one of the directories where the kernel firmware loader or firmware agent will look, such as /lib/firmware.

N If the device stores multiple firmware images in separate regions of non-volatile memory, this parameter may be used to specify which region is to be written. The default is 0, requesting that all regions are written. All other values are driver-dependent.

-l --show-channels Queries the specified network device for the numbers of channels it has. A channel is an IRQ and the set of queues that can trigger that IRQ.

-L --set-channels Changes the numbers of channels of the specified network device.

rx N Changes the number of channels with only receive queues.

tx N Changes the number of channels with only transmit queues.

other N Changes the number of channels used only for other purposes e.g. link interrupts or SR-IOV co-ordination.

combined N Changes the number of multi-purpose channels.

-m --dump-module-eeprom --module-info Retrieves and if possible decodes the EEPROM from plugin modules, e.g SFP+, QSFP. If the driver and module support it, the optical diagnostic information is also read and decoded.

--show-priv-flags Queries the specified network device for its private flags. The names and meanings of private flags (if any) are defined by each network device driver.

--set-priv-flags Sets the device's private flags as specified.

flag .A1 on off Sets the state of the named private flag.

--show-eee Queries the specified network device for its support of Energy-Efficient Ethernet (according to the IEEE 802.3az specifications)

--set-eee Sets the device EEE behaviour.

.A2 eee on off Enables/disables the device support of EEE.

.A2 tx-lpi on off Determines whether the device should assert its Tx LPI.

advertise N Sets the speeds for which the device should advertise EEE capabilities. Values are as for --change advertise

tx-timer N Sets the amount of time the device should stay in idle mode prior to asserting its Tx LPI (in microseconds). This has meaning only when Tx LPI is enabled.

--set-phy-tunable Sets the PHY tunable parameters.

.A2 downshift on off Specifies whether downshift should be enabled.

count N Sets the PHY downshift re-tries count. .TE

.A2 fast-link-down on off Specifies whether Fast Link Down should be enabled and time until link down (if supported).

msecs N Sets the period after which the link is reported as down. Note that the PHY may choose the closest supported value. Only on reading back the tunable do you get the actual value. .TE

.A2 energy-detect-power-down on off Specifies whether Energy Detect Power Down (EDPD) should be enabled (if supported). This will put the RX and TX circuit blocks into a low power mode, and the PHY will wake up periodically to send link pulses to avoid any lock-up situation with a peer PHY that may also have EDPD enabled. By default, this setting will also enable the periodic transmission of TX pulses.

msecs N Some PHYs support configuration of the wake-up interval to send TX pulses. This setting allows the control of this interval, and 0 disables TX pulses if the PHY supports this. Disabling TX pulses can create a lock-up situation where neither of the PHYs wakes the other one. If unspecified the default value (in milliseconds) will be used by the PHY. .TE

--get-phy-tunable Gets the PHY tunable parameters.

downshift For operation in cabling environments that are incompatible with 1000BASE-T, PHY device provides an automatic link speed downshift operation. Link speed downshift after N failed 1000BASE-T auto-negotiation attempts. Downshift is useful where cable does not have the 4 pairs instance. Gets the PHY downshift count/status.

fast-link-down Depending on the mode it may take 0.5s - 1s until a broken link is reported as down. In certain use cases a link-down event needs to be reported as soon as possible. Some PHYs support a Fast Link Down Feature and may allow configuration of the delay before a broken link is reported as being down. Gets the PHY Fast Link Down status / period.

energy-detect-power-down Gets the current configured setting for Energy Detect Power Down (if supported).

--reset Reset hardware components specified by flags and components listed below

flags N Resets the components based on direct flags mask

mgmt Management processor

irq Interrupt requester

dma DMA engine

filter Filtering/flow direction

offload Protocol offload

mac Media access controller

phy Transceiver/PHY

ram RAM shared between multiple components ap Application Processor

dedicated All components dedicated to this interface

all All components used by this interface, even if shared

--show-fec Queries the specified network device for its support of Forward Error Correction.

--set-fec Configures Forward Error Correction for the specified network device. Forward Error Correction modes selected by a user are expected to be persisted after any hotplug events. If a module is swapped that does not support the current FEC mode, the driver or firmware must take the link down administratively and report the problem in the system logs for users to correct.

encoding auto | off | rs | baser [...] Sets the FEC encoding for the device. Combinations of options are specified as e.g. encoding auto rs ; the semantics of such combinations vary between drivers.

auto Use the driver's default encoding
off Turn off FEC
RS Force RS-FEC encoding
BaseR Force BaseR encoding

-Q|--per-queue Applies provided sub command to specific queues.

queue_mask %x Sets the specific queues which the sub command is applied to. If queue_mask is not set, the sub command will be applied to all queues.

sub_command Sub command to apply. The supported sub commands include --show-coalesce and --coalesce.

BUGS
Not supported (in part or whole) on all network drivers.
AUTHOR
ethtool was written by David Miller. Modifications by Jeff Garzik, Tim Hockin, Jakub Jelinek, Andre Majorel, Eli Kupermann, Scott Feldman, Andi Kleen, Alexander Duyck, Sucheta Chakraborty, Jesse Brandeburg, Ben Hutchings, Scott Branden.
AVAILABILITY
ethtool is available from R http://www.kernel.org/pub/software/network/ethtool/ E