Dell POWERVAULT MD3620F - Manual (Page 38)

38 Appendix—Hardware Cabling Best Practices
NOTE: If Remote Replication is activated, host port 3 on each RAID controller
module is dedicated for the communication that occurs between the two
storage arrays (primary and secondary virtual disks). If the Remote Replication
premium feature is not being used, these host ports are available for ordinary
host connections.
Cabling for Performance
Data transfer performance is enhanced by maximizing bandwidth, which is
the ability to process more I/O across more channels. Therefore, a
configuration that maximizes the number of host channels and the number
of drive channels available to process I/O maximizes performance. Faster
processing speeds also maximize performance.
In addition to planning a topology that provides maximum performance,
choose a RAID level that suits the planned applications.
Single-Controller and Dual-Controller Topologies
While creating a topology for a RAID enclosure that contains only one RAID
controller module, attach expansion enclosures that contain only one single
environmental services monitor (ESM). Do not attach an expansion
enclosure that contains two ESMs to a single-controller RAID enclosure.
Labeling Cables
Cabling is an important part of creating a robust storage array. Labeling the
cables identifies system components and drive channels. System
maintenance is easier when the cables are correctly identified. Label both
ends of each cable. You can use adhesive office labels that are folded in half
over the ends of each cable. Mark the labels with the port identifiers to which
the cable is connected. Additional information can be provided by using
color-coded cable straps (or ties) to group all cables associated with one
component or drive channel.
If a component fails, the cables must be disconnected, the failed component
replaced, and the cables reattached. Detailed labeling of the cables simplifies
the component replacement process.
If you are adding a new expansion enclosure to an existing configuration,
correctly labeled cables helps identify where to connect the new enclosure.
book.book Page 38 Friday, September 9, 2011 11:26 PM