LINKSTAT(1)LINKSTAT(1)NAMElinkstat - a Craylink monitoring tool
SYNOPSISlinkstat [-e|-x][-c] -a | -h | -r | hwgraph_filename
DESCRIPTIONlinkstat reports on router link performance and error rates. It also
reports error rates on the Hub chip Craylink network interface (NI) and
I/O Interface (II) links.
OPTIONS-c Report information continuously every five seconds.
-e Only report error rates, not performance information. This option is
exclusive with -x.
-x Only report router ports or hub devices that have non-zero error
rates. This option is exclusive with -e and only useful when used
with -a, -h or -r.
-a Report on all links in the system.
-h Report only on hub devices.
-r Report only on router devices.
EXAMPLES
To get information about a particular link, you might try something like
# linkstat /hw/module/1/slot/n1/node/hub/mon
Hub: /hw/module/1/slot/n1/node/hub/mon
NI: Retries 0 (0/Min), SN errs 0 (0/Min), CB errs 0 (0/Min)
II: SN errs 0 (0/Min), CB errs 0 (0/Min)
SN errs refers to sequence number errors. Some number of these is
normal. Do not be alarmed by SN error counts. CB errs refers to
checkbit errors. None of these errors are fatal, but high checkbit error
or retry counts may indicate a problem.
# linkstat /hw/module/1/slot/r2/router/mon
Router: /hw/module/1/slot/r2/router/mon
Port 3: Utilization: bypass 0% receive 2% send 2%
Retries 71847 (6/Min), SN errs 116395 (19/Min), CB errs 31196
(2/Min)
Port 5: Utilization: bypass 9% receive 13% send 20%
Retries 25087 (2/Min), SN errs 497298 (38/Min), CB errs 30417650
(2914/Min)
Port 6: Utilization: bypass 0% receive 4% send 3%
Retries 46394 (4/Min), SN errs 6252865 (599/Min), CB errs 5557
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LINKSTAT(1)LINKSTAT(1)
(0/Min)
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This example is from a sick system. The checkbit errors on port 5 are
excessive. All of the other numbers are within spec. Send and receive
utilizations indicate how much of a port's peak bandwith is being used.
Bypass indicates what percentage of traffic is able to use the latency-
reducing bypass feature of the router chip.
# linkstat-a
This example would display information about all of the links on the
system.
RESTRICTIONS
If there are no routers present, the linkstat-a output will include a
message like this one:
Cannot access /hw/module/*/slot/r*/router/mon:
No such file or directory
Do not be alarmed.
SEE ALSOxbstat(1m), nstats(1), sn(1), hwgraph(4).
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