linkloop - verify LAN connectivity with link-level loopback
linkloop [-i PPA] [-n count] [-r rif] [-s size] [-t timeout]
[-v] linkaddr ...
The linkloop command uses IEEE 802.2 link-level test frames to check
connectivity within a local area network (LAN).
linkaddr is the hardware station address of a remote node. Several
addresses can be specified at one time.
linkloop tests the connectivity of the local node and the remote node
specified by each hardware station address. The hardware station
address of a remote node can be found by executing lanscan on the
remote node. This hardware station address is usually represented as
a hexadecimal string prefixed with 0x. It can also be represented as
a octal string prefixed with 0 or as a decimal string. The hardware
station address must not be a multicast or broadcast address.
linkloop recognizes the following options:
-i PPA Specify the PPA to use. If this option is
omitted, linkloop uses the first PPA it
encounters in an internal data structure.
-n count Set the number of frames to transmit. If
count is 0, linkloop transfers frames
indefinitely until an interrupt signal
(defined by the user shell) is received. The
default value for count is 1.
-r rif Specify the particular bridge route over
which token ring packets should be delivered.
rif is the routing information field used for
token-ring networks. Its value is given as
an even number of hexadecimal bytes separated
by colons, up to a maximum of 16 bytes.
-s size Set the size in bytes of the data message to
send. The maximum data size is dependent on
the type of LAN link being used. The default
value is the maximum data byte count that can
be used for the particular link.
-t timeout Set the amount of time in seconds to wait for
a reply from the remote node before aborting.
If timeout is 0, linkloop waits indefinitely
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for a reply. The default value is 2 seconds.
-v Set the verbose option. In addition to the
regular summary of test results, this option
displays more extensive error information.
If there are header or length errors,
appropriate messages are displayed. All
verbose output is preceded by the number of
replies accepted before an error occurred.
Connectivity Test Results
linkloop aborts upon receipt of an interrupt signal. If aborted, the
current results are printed.
linkloop prints the result of the link-level connectivity test. If
the test fails, it prints a summary of the test and indicates the type
of error. The possible messages are:
address has bad format
An incorrect hardware station address was entered on the command
address is not individual
The station address entered on the command line is either a
multicast or broadcast address.
Total number of frames sent.
frames received correctly
Total number of frames received without errors.
frames with length error
Received frame length does not match transmitted frame length.
If the verbose option is set, the length received is printed.
frames with data error
Received frame does not match transmitted frame.
frames with header error
Number of frames received containing unexpected frame header
information. Either the source address does not match the remote
address, the destination address does not match the local
address, or the control field is not the TEST frame control
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field. These frames are ignored. linkloop continues to try to
receive the reply frame until the read operation times out.
reads that timed out
Count of how many read operations timed out before the reply was
illegal count parameter
The count specified in the -n option is a negative integer, or
the number specified is too large for the local computer.
illegal timeout parameter
The timeout specified in the -t option is a negative integer, or
the value specified multiplied by 1000 is too large for the local
illegal size parameter
The size specified in the -s option is not in the range from 0 to
the maximum link data size. Remember that the maximum link data
size can vary in value for different LAN connection types. The
current MTU can be obtained with the linkloop command.
No valid interface associated with PPA
The PPA specified in the -i option is not a valid PPA.
Unable to open device file /dev/dlpi
Device file /dev/dlpi does not exist.
invalid rif parameter
The rif value in the -r option is invalid.
rif parameter too long
The number of bytes in rif in the -r option exceeded 16, which is
the maximum allowed.
rif parameter length must be even
The number of bytes in rif in the -r option is odd. The number
of bytes must be even.
linkloop was developed by HP.
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lanadmin(1M), lanscan(1M), lan(7).
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