FRCONFIG(8) BSD System Manager's Manual FRCONFIG(8)NAMEfrconfig - configure frame relay parameters
SYNOPSISfrconfig interface [command ...] [...]
DESCRIPTION
This utility may change dramatically in future releases.
The frconfig utility allows the setting and retrieving of the frame relay
parameters. The interface must be configured to the fr linktype prior to
using frconfig. This is done with the ifconfig(8) command:
ifconfig interface linktype fr
Once configured for frame relay, 3 types of information may be retrieved:
configuration parameters, static DLCI (Data Link Connection Identifier)
maps, and dynamic DLCI maps. Calling frconfig with just the interface
will display the first two types of information. The information is dis-
play is in format that allows it to be replayed to frconfig. (e.g.,
``frconfig ntwo0 $(frconfig ntwo0)'' is a no-op.) Calling frconfig with
the command -map will cause it to display the dynamic DLCI map.
When first configured, the output of frconfig interface will be:
interface
type DTE
lmi ANSI
N391 6
N392 3
N393 4
T391 10
maxframe 4000
fecn unused
becn unused
niarps 3
discard 0
mode P2P
default 0
Aside from the interface, the parameters, which are also the list of com-
mands to frconfig are:
type Either DTE (Data Terminal Equipment) or DCE (Date Computer
Equipment). DCE mode is used when mimicking a switch. DTE
mode is almost always the correct setting.
lmi One of ORIG, ANSI, or CCITT. This determines the format of
the LMI (Local Management Interface) messages.
T391 Link integrity verification polling timer. This value, in
seconds, is how often to send LMI status request messages.
N391 Polling cycles for full status of all PVCs. Every T391 sec-
onds a status message is sent. Every N391th message requests
a full reporting of DLCIs. New DLCIs are only discovered
when a full status message is requested.
N392 Number of errors occurring during N393 monitored events that
cause the link to become unreliable. Must be no greater than
N393.
N393 Monitored events counter. Number of events used when looking
for errors.
maxframe Maximum frame size, in bytes.
fecn Forward Explicit Congestion Notification. Currently ignored
by the system.
becn Backward Explicit Congestion Notification. Currently ignored
by the system.
niarps Number of IARP requests allowed per T391 seconds.
discard Determine setting of the discard eligibility bit. Currently
the only meaningful values are 0 (never set DE) and 1 (set DE
for IP packets, but not LMI packets).
mode Either P2P (Point-To-Point) or MDNB (Multiple Destination No
Broadcast). When set to P2P ifconfig must be called with a
local and remote address:
ifconfig interface local-addr remote-addr
When set to MDNB the ifconfig command should contain a local
address and netmask:
ifconfig interface local-addr/netmask
Where netmask is the number of bits in the network mask
(e.g., 24). When MDNB mode is used all the IP addresses as-
sociated with the frame relay network must be within the same
subnet. MDNB is recommended when more than a single DLCI is
to be used.
default The DLCI to use when no DLCI is associated with the destina-
tion IP address of the packet. This is most useful in MDNB
mode.
To receive a usage message about any individual command use:
frconfig interface command
In normal circumstances, the only steps needed in setting up a Frame Re-
lay link are:
ifconfig interface linktype fr
frconfig interface ...
ifconfig local-address ...
At this point LMI messages will be sent out and as new PVCs (Permanent
Virtual Circuits) are discovered IARP (Inverse Address Resolution Proto-
col) packets are sent to the associated DLCI to determine the IP address
at the remote side. (The ifconfig(8) command only affects routing, it
does not determine DLCI to IP address mapping). If the remote side does
not support IARP, or if it reports incorrect information, static DLCI
mapping may be used. To statically map an IP address to a DLCI use the
following syntax:
frconfig interface dlci index remote-address
This will cause packets destined for the IP address remote-address to be
sent to DLCI index. The mapping may be removed by the command:
frconfig interface -dlci index remote-address
Multiple mappings may be made for a single DLCI. To remove all mappings
use a remote-address of 0. When a new PVC is discovered with a DLCI that
is statically mapped, no IARP packet is sent, only the static mapping is
used.
Dynamic DLCI maps are the ones actually used by the system. These maps
are dynamically created by the results of IARP queries or taken from
static DLCI maps. Dynamic DLCI maps are read-only and reflect all the
active DLCIs that have associated IP addresses. Unlike static DLCI maps,
only active DLCIs are reported. Static DLCI maps may be made for any DL-
CI, real or imaginary (or even impossible).
DCE MODE
When in DCE mode all DLCIs must have static maps. The DCE determines
what PVCs/DLCIs are available. The driver currently is not smart about
this and will relate all DLCIs to all DTEs, even the DLCI that others use
to contact that DTE. Conversely, a DLCI will be advertised even if the
associated client is not active.
SEE ALSOifconfig(8)BSDI BSD/OS August 4, 1997 3