G A L A X Y ® A U R O U R A C O N F I G U R A T I O N A N D S Y S T E M I N T E G R A T I O N G U I D E
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Section 4 Troubleshooting Guide
going in or out. The lenses can occasionally get misaligned or move during the
glue’s curing process. Everything surrounding the lenses (just about) is plastic.
Two mechanical problems which can occur are because of this plastic: It’s
possible that a cable may be misassembled by putting the wrong lens on the
wrong conduit, flipping one end of the cable upside-down. The way to tell if this
is occurring is to plug the cable into an operating Fibre channel device, and
compare the other end to what it is plugging into – if the laser on what it is
plugging into is coming from the same side as the laser coming from the cable,
the cable is defective. The other mechanical problem – the plastic portion of
the plugs can be broken easily, so care must be used when inserting or
especially when removing the cables. Now the cable itself is made of
fiberglass, which is essentially plastic. If you took a clear semi-thick piece of
plastic and bent it, you would find that where it bends, it turns opaque (white),
and you can’t see through that part. It is similar with the fibre itself – you don’t
want to bend it if possible – I’d say you don’t want to go around a bend with an
equivalent diameter less than a 3 inch circle. If it is bent too far, although you
won’t be able to see it, the cable inside will turn opaque, preventing the beam
from passing through properly. If this happens, the cable is useless. When the
Fibre cables or cards are shipped, they have protective covers. The cover on
the card is mainly to keep dust out (If dust gets in-between the emitter/detector
and the lens, it might impair data transmission). However the covers on the
cable are for a different reason – to protect the lenses from getting scratched.
If the lenses on the cable become scratched, they will also impair the ability for
the cable to carry the light from the laser.
4.17
Troubleshooting Aurora’s Client Related Problems
Fibre Based Clients
Assuming there are no problems on the array, in order for a client to be able to
see a LUN, there is a certain chain of items which must be present as in the
following diagram:
