Setting Solaris Network Tunable Parameters

To view the network tunable parameters on a Solaris machine, use the commands listed below:

bash-2.03# ndd -get /dev/hme ? | pg
? (read only)
transceiver_inuse (read only)
link_status (read only)
link_speed (read only)
link_mode (read only)
ipg1 (read and write)
ipg2 (read and write)
use_int_xcvr (read and write)
pace_size (read and write)
adv_autoneg_cap (read and write)
adv_100T4_cap (read and write)
adv_100fdx_cap (read and write)
adv_100hdx_cap (read and write)
adv_10fdx_cap (read and write)
adv_10hdx_cap (read and write)
autoneg_cap (read only)
100T4_cap (read only)
100fdx_cap (read only)
100hdx_cap (read only)
10fdx_cap (read only)
10hdx_cap (read only)
lp_autoneg_cap (read only)
lp_100T4_cap (read only)

output truncated

The (read and write) parameters can be changed on the system.

You should be root to change the parameters. These changes will be temporary.

The following is a common example:

# ndd -get /dev/hme link_speed

The example above specifies that the link_speed (Ethernet) is 100Mbps. To change that to 10Mbps, we can do the following:

# ndd -get /dev/hme link_speed ( present condition)
# ndd -set /dev/hme instance 0 ( if there is only one nic then no issues )
# ndd -set /dev/hme link_speed 0
# ndd -get /dev/hme link_speed

Other interesting parameters that can be changed are the ip_forwarding feature. These were normally carried out on firewalls. Now, this is done by the firewalls during installation.

The command is as follows:

#ndd -set /dev/ip hme0:ip_forwarding 0
#ndd -get /dev/ip hme0:ip_forwarding

A value of 0 specifies a disabled condition.

Interesting Modules are listed below:


To make the changes permenant, make entries in the /etc/system file.

The Conversation

Follow the reactions below and share your own thoughts.

  • Real_lmd

    No way, not at all ndd tunables acceptable in /etc/system. To do that you must use service script to set up TCP/IP stack tunables during startup.