How to check NIC speed in Unix

Fast Ethernet connection is essential for some operations to work properly.
backup, oracle RAC all require fast Ethernet connection.

Different OS provides different commands to check the network speed currently running.

In Linux, we can run mii-tool or ethtool to check the network speed. Both commands require root access

[root@localhost eth0]# mii-tool eth0
eth0: no autonegotiation, 100baseTx-FD, link ok

[root@localhost eth0]# ethtool eth0
Settings for eth0:
        Supported ports: [ TP ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Speed: 1000Mb/s
        Duplex: Full
        Port: Twisted Pair
        PHYAD: 0
        Transceiver: internal
        Auto-negotiation: on
        MDI-X: Unknown
        Supports Wake-on: umbg
        Wake-on: d
        Current message level: 0x00000007 (7)
        Link detected: yes

In Solaris, we can run kstat or dladm to check the network speed

$ kstat -m igb -i 0 | egrep 'link_autoneg|link_speed|link_duplex'
        link_autoneg                    1
        link_duplex                     2
        link_speed                      100

The output shows that, igb0 is running autonegotiation, 100 Mbps full-duplex

if we have root access, we can run dladm or ndd to check the network speed.

In AIX, we can run entstat to check network speed.
if we want to check the speed of en0

$ entstat -d en0 | egrep '^Device|^Media'
Device Type: 2-Port 10/100/1000 Base-TX PCI-X Adapter (14108902)
Media Speed Selected: Auto negotiation
Media Speed Running: 100 Mbps Full Duplex

We can see that en0 supports upto 1000 Mbps, but it's running 100 Mbps Full Duplex.

In HP-UX, we can run lanadmin or nwmgr to check the network speed.
lanadmin output is shorter

$ /usr/sbin/lanadmin -x 0
Speed = 1000 Full-Duplex.
Autonegotiation = On.

we can also use nwmgr to get detailed information

$ /usr/sbin/nwmgr --get --stats -C lan -I 0

***          lan0 64 bit MIB statistics:
Interface Name               = lan0
PPA Number                   = 0
Description                  = lan0 HP PCI 1000Base-T Release B.11.31.0809.01
Interface Type               = 1000Base-T
MTU Size                     = 1500
Speed                        = 1 Gbps
Station Address              = 0x0A527E583C90
Administration Status        = UP
Operation Status             = UP
Last Change                  = Wed Mar 20 05:58:50 2013
Inbound Octets               = 166627219743
Inbound Unicast Packets      = 975967141
Inbound Multicast Packets    = 1124454
Inbound Broadcast Packets    = 6566058
Inbound Discards             = 1821280
Inbound Errors               = 0
Inbound Unknown Protocols    = 1124769
Outbound Octets              = 185484791114
Outbound Unicast Packets     = 968101273
Outbound Multicast Packets   = 0
Outbound Broadcast Packets   = 1618
Outbound Discards            = 0
Outbound Errors              = 0
Counter Discontinuity Time   = Wed Mar 20 05:58:50 2013
Physical Promiscuous Mode    = FALSE
Physical Connector Present   = TRUE
Interface Alias              =
Link Up/Down Trap Enable     = Enabled