Ethtool was updated and picked up a bunch of new command line switches in Gaia kernel 3.10. From expert mode try ethtool -m (interfacename). Under kernel 2.6.18 ethtool does not have the -m option available, but try mii-diag -g (interfacename). On Gaia 3.10 you should see something like this with ethtool -m:
Identifier : 0x03 (SFP)
Extended identifier : 0x04 (GBIC/SFP defined by 2-wire interface ID)
Connector : 0x07 (LC)
Transceiver codes : 0x00 0x00 0x00 0x01 0x20 0x40 0x0c 0x05
Transceiver type : Ethernet: 1000BASE-SX
Transceiver type : FC: intermediate distance (I)
Transceiver type : FC: Shortwave laser w/o OFC (SN)
Transceiver type : FC: Multimode, 62.5um (M6)
Transceiver type : FC: Multimode, 50um (M5)
Transceiver type : FC: 200 MBytes/sec
Transceiver type : FC: 100 MBytes/sec
Encoding : 0x01 (8B/10B)
BR, Nominal : 2100MBd
Rate identifier : 0x00 (unspecified)
Length (SMF,km) : 0km
Length (SMF) : 0m
Length (50um) : 300m
Length (62.5um) : 150m
Length (Copper) : 0m
Length (OM3) : 0m
Laser wavelength : 850nm
Vendor name : JDSU
Vendor OUI : 00:01:9c
Vendor PN : PLRXPL-VI-S24-22
Vendor rev : 1
Optical diagnostics support : Yes
Laser bias current : 21.348 mA
Laser output power : 0.3186 mW / -4.97 dBm
Receiver signal average optical power : 0.3195 mW / -4.96 dBm
Module temperature : 41.70 degrees C / 107.05 degrees F
Module voltage : 3.2947 V
Alarm/warning flags implemented : Yes
Laser bias current high alarm : Off
Laser bias current low alarm : Off
Laser bias current high warning : Off
Laser bias current low warning : Off
Laser output power high alarm : Off
Laser output power low alarm : Off
Laser output power high warning : Off
Laser output power low warning : Off
Module temperature high alarm : Off
Module temperature low alarm : Off
Module temperature high warning : Off
Module temperature low warning : Off
Module voltage high alarm : Off
Module voltage low alarm : Off
Module voltage high warning : Off
Module voltage low warning : Off
Laser rx power high alarm : Off
Laser rx power low alarm : Off
Laser rx power high warning : Off
Laser rx power low warning : Off
Laser bias current high alarm threshold : 10.000 mA
Laser bias current low alarm threshold : 1.000 mA
Laser bias current high warning threshold : 9.000 mA
Laser bias current low warning threshold : 2.000 mA
Laser output power high alarm threshold : 0.8000 mW / -0.97 dBm
Laser output power low alarm threshold : 0.1000 mW / -10.00 dBm
Laser output power high warning threshold : 0.6000 mW / -2.22 dBm
Laser output power low warning threshold : 0.2000 mW / -6.99 dBm
Module temperature high alarm threshold : 90.00 degrees C / 194.00 degrees F
Module temperature low alarm threshold : -40.00 degrees C / -40.00 degrees F
Module temperature high warning threshold : 85.00 degrees C / 185.00 degrees F
Module temperature low warning threshold : -40.00 degrees C / -40.00 degrees F
Module voltage high alarm threshold : 4.0000 V
Module voltage low alarm threshold : 0.0000 V
Module voltage high warning threshold : 3.6450 V
Module voltage low warning threshold : 2.9550 V
Laser rx power high alarm threshold : 1.6000 mW / 2.04 dBm
Laser rx power low alarm threshold : 0.0100 mW / -20.00 dBm
Laser rx power high warning threshold : 1.0000 mW / 0.00 dBm
Laser rx power low warning threshold : 0.0200 mW / -16.99 dBm
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