IP(1) XR32 REFERENCE MANUAL 19/1/2013
COMMAND
IP -- Display / Change IP routing parameters.
SYNOPSIS
IP QUIET [level]
IP ROUTES
IP ROUTE ADD <host>[/len] <gateway> <port> [mode [metric]]
IP ROUTE ADDPRIVATE <host/bits> encap <gateway>
IP ROUTE CMD [0-1]
IP ROUTE DROP <host> <len>
IP ROUTE DEFAULT <port> [gateway [mode]]
IP ROUTE LOAD
IP ROUTE LOOKUP <host>
IP TTL [ttl]
AVAILABILITY
The IP ROUTES command is available to all, providing it
hasn't been disabled by sysop. The remaining commands are
sysop-only.
DESCRIPTION
The IP commands are used to display and alter some of the IP
parameters, and the contents of the table responsible for
routing of IP datagrams.
The arguments are as follows:
<host> Target hostname or IP address. IP address is
preferred, as it is more efficient. Route default
must always be an IP address.
<len> No. of bits to be matched (from left) 0-32
<gateway> Destination gateway IP address in dotted quad.
<port> Port number on which to route the datagram.
For encapsulated modes (e,i,u), Netrom and reject
modes (r and s) this is ignored and should be 0.
For IPUDP, this can optionally specify the UDP
service number to use (default=94).
<mode> How the datagram is routed, as follows..
d = Datagram (direct)
e = Encap (ip-over-ip protocol 4)
i = IPIP (ip-over-ip protocol 94)
n = Netrom (ip-over-netrom)
r = Reject
s = Silent discard
u = IPUDP (ip-over-UDP)
v = Virtual circuit (ip-over-ax25)
w = Winsock
The usual mode is "datagram". However, on less
than perfect RF links, better performance can be
obtained by using Virtual Circuit mode. Netrom
mode is inefficient, but can "tunnel" datagrams
across non-ip parts of the network.
Encap, IPIP and IPUDP are used for tunneling
amateur IP across the public internet.
Reject and Silent discard are used to suppress
bouncing and looping.
Winsock mode is a dummy mode. It tells XR32 to use
Windows' IP stack for anything matching the entry,
but see Caveats below.
OPTIONS
The QUIET subcommand is used to display or set XR32's
"stealth" level, i.e. how it responds to ICMP echo requests
and TCP port probes. If the level is zero, XR32 behaves
normally. If a non-zero argument is supplied, XR32 becomes
stealthy. The stealth level is specified by adding the
following values:
1 Suppress ICMP echo replies.
2 Suppress Protocol unreachable
4 Suppress TCP refusals
8 Suppress all ICMP errors
ROUTE CMD is used to allow / disallow the IP ROUTES and
IPR[outes] commands from being used by non-sysops. On amateur
networks however, it is considered bad practice to hide IP
routing.
The ROUTE DEFAULT subcommand sets up a default route which is
used when no other route is found. If no gateway is
specified, the target will be assumed to be a direct
neighbour. If not specified, the mode defaults to datagram.
The ROUTE ADD subcommand adds an entry to the routing table.
The first argument is the target host IP address, with optional
mask. e.g. 44.131.90.1/32 means "match all 32 bits", whereas
44.131.90.0/24 means "match the most significant 24 bits", and
would route all 256 addresses from 44.131.90.0 to
44.131.90.255.
The second argument is the "gateway" address, i.e. the address
of the system which can handle the datagram.
The third argument is the port to route the datagram on, and
the last argument is the mode (see above).
The ROUTE ADDPRIVATE subcommand is the same as ROUTE ADD,
except that it marks the route "private", hiding it from
non-sysops. The regular form has the same syntax as ROUTE ADD
and can accept any mode, whereas the shortened form is
provided for backward compatibility with "encap.txt", and can
only accept mode "encap".
The ROUTE DROP subcommand removes an entry from the table.
Both the target host and the mask must match.
The ROUTE LOAD subcommand clears the existing IP parameters
and tables, and reloads them from IPROUTE.SYS.
The ROUTE LOOKUP subcommand displays the gateway and port
which XR32 will use to reach a given destination.
The TTL subcommand specifies the default "Time To Live" for
datagrams originating at this host.
EXAMPLES
IP ROUTE DEFAULT 3 44.131.90.6 v
IP ROUTE ADD 44.131.95.0/24 44.131.95.240 9 d
IP ROUTE DROP 44.131.97.1 32
IP ROUTE LOOKUP bbc.co.uk
FILES
The IP commands may be used in IPROUTE.SYS and BOOTCMDS.SYS
but the only ones that have any meaning in those locations
are IP ROUTE ADD, IP ROUTE DEFAULT, IP TTL and IP QUIET. It
is usual to define IP routing in IPROUTE.SYS.
When XR32 boots, it first reads IPROUTE.SYS, then ENCAP.TXT,
then finally BOOTCMDS.SYS.
CAVEATS
Mode "w" should be used with caution. It means "Use Windows
TCP/IP services to reach this destination", and is intended
only as a last resort, e.g. when the NdisXpkt driver is not
being used.
For "security reasons" Windows does not allow applications
to route raw IP traffic through it's stack. It actively
blocks IP protocol 4 (IPEncap), and puts severe restrictions
on TCP and UDP traffic.
Windows allows XR32 to originate and terminate TCP, UDP,
IPIP, ICMP and AXIP, but not to *route* those protocols.
Therefore you may Telnet and Ping from XR32, but you are not
allowed to route 3rd party traffic, e.g. from RF to Internet.
NOTES
The IP routing table is necessary only for IP, and does not
take any part in normal ax25 and Netrom activities. See the
full manual for details on how to set up the IP system.
Please do not over-use ADDPRIVATE, as it hinders the
diagnosis of networking problems, and many consider it to
be contrary to the spitit of Ham Radio.
SEE ALSO
IP-PRIMER -- IP Addressing / Routing Primer.
IPROUTE(1) -- Display IP Routes
IP(1) END OF DOCUMENT
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