User guide

Galaxy 55 User Guide
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Standard DB9 FC-AL cables are used to link the Tx connector on one enclosure to the Tx/Rx connector of the next
and so on for the required number of enclosures in the chain, as shown in Figure 2–14. The loop is completed by
linking the Tx connector on the last enclosure in the chain back to the host computer
Note If the host connections are via a single connector a splitter must be used to separate the Tx and Rx signals.
Important Loss of power to any enclosure within such a loop will cause the loop to fail. The use of a FC-AL
hub (Figure 2–15) to connect to each enclosure will allow the removal of any enclosure (through
physical removal or power loss) without loss of the entire FC-AL loop.
2.7.2 Connecting Multiple Enclosures (2x6-FC-DC-IO Module)
You may use either one of each pair of HSSDC connectors to connect to another device or enclosure within the loop
LED indicators are fitted for each pair of connectors.
• If a Single connection is made the LED will illuminate Amber.
• If Both connections have a valid FC_AL signal the LED will illuminate Green.
2.7.3 Connecting Multiple Enclosures (2x6-FC-DC-IO Module) Expansion to Galaxy
The following rules apply when you are attaching Galaxy 55 enclosures to an Galaxy RAID enclosure:
• Each enclosure should use “hard addressing”. To ensure that this is the case, Set the ID (AL_PA) thumbwheel
switch on each expansion enclosure to a different setting 1 to 7).
Important Do not use a setting of 0 as this is the RAID enclosure ID range.
Figure 2–14 Daisy Chaining Multiple Enclosures
Figure 2–15 FC-AL Hub