root@vbox3:/tmp# svccfg <<EOM
select /system/identity:node
#listprop config
setprop config/nodename="newhost"
setprop config/loopback="newhost"
refresh
EOM
And this is how to permanently change your static IP-Address in Solaris 11, if you are not using NWAM:
root@vbox3:/tmp# svcs svc:/network/physical:nwam
STATE STIME FMRI
disabled Sep_22 svc:/network/physical:nwam
root@vbox3:/tmp# ipadm show-addr
ADDROBJ TYPE STATE ADDR
lo0/v4 static ok 127.0.0.1/8
net0/v4 static ok 192.168.3.17/24
lo0/v6 static ok ::1/128
net0/v6 addrconf ok fe80::a00:27ff:febd:7496/10
root@vbox3:/tmp# ipadm delete-addr net0/v4
root@vbox3:/tmp# ipadm create-addr -T static -a 192.168.3.18/24 net0/v4
root@vbox3:/tmp# ipadm show-addr
ADDROBJ TYPE STATE ADDR
lo0/v4 static ok 127.0.0.1/8
net0/v4 static ok 192.168.3.18/24
lo0/v6 static ok ::1/128
net0/v6 addrconf ok fe80::a00:27ff:febd:7496/10
root@vbox3:/tmp# exit