1The following instructions are applicable to Tru64 UNIX 
2(formerly Digital UNIX (formerly DEC OSF/1)) version 4.0, and
3probably to later versions as well; at least some options apply to
4Digital UNIX 3.2 - perhaps all do.
5
6In order to use kernel packet filtering on this system, you have
7to configure it in such a way:
8
9Kernel configuration
10--------------------
11
12The packet filtering kernel option must be enabled at kernel
13installation.  If it was not the case, you can rebuild the kernel with
14"doconfig -c" after adding the following line in the kernel
15configuration file (/sys/conf/<HOSTNAME>):
16
17	option PACKETFILTER
18
19or use "doconfig" without any arguments to add the packet filter driver
20option via the kernel option menu (see the system administration
21documentation for information on how to do this).
22
23Device configuration
24--------------------
25
26Devices used for packet filtering must be created thanks to
27the following command (executed in the /dev directory):
28
29	./MAKEDEV pfilt
30
31Interface configuration
32-----------------------
33
34In order to capture all packets on a network, you may want to allow
35applications to put the interface on that network into "local copy"
36mode, so that tcpdump can see packets sent by the host on which it's
37running as well as packets received by that host, and to put the
38interface into "promiscuous" mode, so that tcpdump can see packets on
39the network segment not sent to the host on which it's running, by using
40the pfconfig(1) command:
41
42	pfconfig +c +p <network_device>
43
44or allow application to put any interface into "local copy" or
45"promiscuous" mode by using the command:
46
47	pfconfig +c +p -a
48
49Note: all instructions given require root privileges.
50