Wednesday, October 31, 2007

Figuring out your NIC's speed and duplex on Solaris

Here's another one admins and users have to do all time. If there's ever an issue with networking, you need to be able to confidently say that your NIC is up at 1Gb full duplex (or whatever your network admin insists).

The way to check this has changed somewhat in Solaris 10, but the old way to check is still available; although not totally reliable.

For instance, you can use "ndd" in all flavors of Solaris (at least from 2.6 up) to get information from /dev/hme (or whatever your NIC's device driver is). Generally, you would look at the speed and duplex settings using the following commands (slight variation depending on NIC's - e.g. 100Mb hme's don't have values for the 1000 Mb queries)

The following commands are pretty useful, and non-destructive, for any device driver, even though you'll get errors for all the stuff that isn't supported:

/usr/sbin/ndd -set /dev/ce instance 0
/usr/sbin/ndd -get /dev/ce adv_1000fdx_cap
/usr/sbin/ndd -get /dev/ce adv_1000hdx_cap
/usr/sbin/ndd -get /dev/ce adv_100fdx_cap
/usr/sbin/ndd -get /dev/ce adv_100hdx_cap
/usr/sbin/ndd -get /dev/ce adv_10fdx_cap
/usr/sbin/ndd -get /dev/ce adv_10hdx_cap
/usr/sbin/ndd -get /dev/ce adv_autoneg_cap


Of course, replace the "/dev/ce" with your particular driver. The only downside to this hack-and-slash method is that you may see 1's (indicating that the parameter is set) rather than 0's (indicating that the paramet is not set) in more than one place (like in adv_1000fdx_cap , adv_100hdx_cap and adv_autoneg_cap all at once ???)

The best way to do it, in my experience is to use either "netstat -k" (In Solaris up to, and including, version 9) or "kstat -p."

In Solaris 9, assuming the same NIC driver and instance "ce0," you can do the following to find out the status of your NIC:

netstat -k ce|grep 0|egrep 'link_speed|link_dupl'

On Solaris 10, you'd do this:

kstat -p|grep ce0|egrep 'speed|dupl'

Basically, the speed should be 1000 for Gb, 100 for 100Mb, etc. Your duplex is represented numerically as either 0, 1 or 2.

0 = No Duplex (or Down)
1 = Half Duplex
2 = Full Duplex


This output is great to show anyone who doubts your conviction ;)

Take care,

, Mike