Installing QFX3008-I Interconnect Device Mounting Hardware on Two-Post Racks

Before you install the QFX3008-I Interconnect device in a two-post rack, you must first install mounting hardware on the rack (see Figure 1). The spacer bars are not needed for this mounting option; however, you can leave them attached to the front-mounting brackets.

Note: In a rack, the device uses 21 U. You can mount two QFX3008-I Interconnect devices on a 42 U rack provided that the racks meet the strength requirements to support the combined weight of the devices. If you are mounting two QFX3008-I Interconnect devices on a rack, mount the first device on the bottom of the rack.

Figure 1: Installing the Mounting Hardware for a Two-Post Rack

For a two-post rack, Table 1 specifies the holes in which you insert mounting screws (an X indicates a mounting hole location), and cage nuts if needed. The hole distances are relative to one of the standard “U” divisions on the rack. For reference, the bottom of all mounting shelves is at 0.04 in. (0.02 U) above a U division.

Table 1: Two-Post Rack Mounting Hole Locations

Hole	Distance Above “U” Division		Large Shelf	Small Shelf
30	17.26 in. (43.8 cm)	9.86 U	X
27	15.51 in. (39.4 cm)	8.86 U	X
24	13.76 in. (34.9 cm)	7.86 U	X
21	12.01 in. (30.5 cm)	6.86 U	X
18	10.26 in. (26.0 cm)	5.86 U	X
15	8.51 in. (21.6 cm)	4.86 U	X
12	6.76 in. (17.1 cm)	3.86 U	X
9	5.01 in. (12.7 cm)	2.86 U	X
6	3.26 in. (8.3 cm)	1.86 U	X
3	1.51 in. (3.8 cm)	0.86 U	X	X
2	0.88 in. (2.2 cm)	0.50 U	X	X
1	0.25 in. (0.6 cm)	0.14 U		X

This topic describes these tasks:

1. Installing Cage Nuts for QFX3008-I Interconnect Device Two-Post Rack Mounting
2. Installing the Small Mounting Shelf for QFX3008-I Interconnect Device Two-Post Rack Mounting
3. Installing the Large Mounting Shelf for QFX3008-I Interconnect Device Two-Post Rack Mounting

Installing Cage Nuts for QFX3008-I Interconnect Device Two-Post Rack Mounting

For racks without threaded holes, you must install cage nuts on the rack rails in the locations specified in Table 1 (an X indicates a mounting hole location). The hole distances are relative to one of the standard “U” divisions on the rack rails. The bottom of all mounting shelves is at 0.04 in. (0.02 U) above a U division.

Before you begin, ensure that you have 28 cage nuts appropriate for your rack.

1. On the front rack rail, install cage nuts in the holes specified in Table 1 for the small shelf.
2. On the front rack rail, install cage nuts for the center-mounting brackets. The center-mounting brackets have holes for rack-mounting screws, spaced at 3.5 in. (8.89 cm).
3. On the rear rack rail, install cage nuts in the holes specified in Table 1 for the large shelf.

Installing the Small Mounting Shelf for QFX3008-I Interconnect Device Two-Post Rack Mounting

To mount the chassis on a two-post rack, you must first install the mounting shelves on the rack.

• A Phillips (+) screwdriver, number 2 or 3, depending on the size of your rack mounting screws
• Six mounting screws appropriate for your rack to attach the small mounting shelf to the rack

1. On the front of each rack rail, partially insert a mounting screw into the lowest hole specified in Table 1 for the small shelf.
2. Install the small shelf on the rack. Rest the bottom slot of each ear on a mounting screw. The small shelf installs on the front of the rails, extending away from the rack. The bottom of the small shelf should align with the bottom of the large shelf
3. Partially insert screws into the open holes in the ears of the small shelf.
4. Tighten all the screws completely.

Installing the Large Mounting Shelf for QFX3008-I Interconnect Device Two-Post Rack Mounting

To mount the chassis on a two-post rack, you must first install the mounting shelves on the rack.

• A Phillips (+) screwdriver, number 2 or 3, depending on the size of your rack mounting screws
• 22 mounting screws appropriate for your rack to attach the large mounting shelf to the rack

1. On the rear of each rack rail, partially insert a mounting screw into the lowest hole specified in Table 1 for the large shelf.
2. Install the large shelf on the rack. Rest the bottom slot of each ear on a mounting screw.
3. Partially insert screws into the open holes in the ears of the large shelf.
4. Tighten all the screws completely.