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A frame that contains the back-end switches can still house up to 12 or 16 drives (based on TS3500 or TS4500). FC 4879 supplies the mounting hardware for the back-end switches and a pair of dressed eight fiber cable trunks to connect the back-end switches to the associated back-end drives in the frame. 

Only eight pairs are supplied in the trunks because the preferred practice for TS7770T/TS7760T drive placement states that the drives should be split evenly between two frames. Drives that do not attach to the back-end switches must be cabled directly to the drives because the patch panel was removed. 

Note:  The TS7770T/TS7760T does not support 4 Gbps and 8 Gbps fiber switches for connection to the back-end drives. Currently, a TS7770T/TS7760T must use the 16 Gbps fiber switch to connect to the back-end drives. 

The feasible combination of TS7700, TSx500, and the necessary switches are listed in Table 7-1. 

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a. TS3500 top rack required due to size of switches 

