Consult these guidelines when you plan the location of a control enclosure, and the expansion enclosures that are to be attached to it. A maximal configuration spans multiple racks, one of which contains the file modules. If multiple racks are required, locate the racks next to one another.
Each control enclosure contains two node canisters, forming an I/O group. The guidelines apply on an I/O group by I/O group basis.
The control enclosure requires two standard rack units of space in a rack. If you plan to add expansion enclosures in the future, follow the guidelines for a control enclosure plus one or more expansion enclosures.
If you have one or more expansion enclosures, position the control enclosure in the center of the rack to make cabling easier. Balance the number of expansion enclosures above and below the control enclosure.
Each enclosure requires two standard rack units of space in a rack. Identify the appropriate location for each enclosure by using the numbers on the front of the rack. When you add a single expansion enclosure to an existing network, it is preferable to add the enclosure directly below the control enclosure. When you add a second expansion enclosure, it is preferable to add the enclosure directly above the control enclosure. As more expansion enclosures are added, alternate adding them above and below the control enclosure.
Put the second set of enclosures above or below the first set of enclosures. You can also add the second set of enclosures in a different rack.