4.13) How can I use full-duplex ethernet?

Sun's hme and later fast ethernet adaptors support full-duplex ethernet.

There are several ways of changing the default settings and force full-duplex mode; you may need to alter your switch settings as well. The problem with changing this setting is that it disables auto negotiation. Usually, this causes switches to fall back to half-duplex mode unless they are also configured to use full duplex mode.

It is usual best to leave the settings alone and have both switch and Sun auto-negotiate unless problems arise.

Setting through /etc/system

		set hme:hme_adv_autoneg_cap=0
		set hme:hme_adv_100hdx_cap=0
		set hme:hme_adv_100fdx_cap=1

Setting with ndd

		ndd -set /dev/hme adv_100hdx_cap 0
		ndd -set /dev/hme adv_100fdx_cap 1
		ndd -set /dev/hme adv_autoneg_cap 0

In case you have multiple instances, you need to select the specific hme instance first, e.g., use the following to select hme1:

		ndd -set /dev/hme instance 1

If you need to query the device, you can interrogate various variables such as ``link_status'', ``link_speed'', etc.

Setting "adv_autoneg_cap", not necessarily changing it, will cause re-negotiating of link speed/duplex settings.

The dfme device cannot configured using /etc/system but are configured either with ndd (but on per-device nodes /dev/dfme0, dev/dfme1) or by editing dfme.conf.