Cisco 2901-2811 Rack Mount Kit ACS-2901-RM-19. For rack installation of Cisco 2901-2811 in 19 inches rack, the rack kit includes screws.
Rack-Mounting the Chassis
Cisco 2900 series and 3900 series routers can be installed in 19-inch (48.26-cm) EIA and 23-inch (58.42-cm) Southwestern Bell Corporation (SBC) racks. The Cisco 3900 series routers can also be mounted in a 600-mm ETSI rack. Use the standard brackets shipped with the router for mounting the chassis in a 19-inch EIA rack; you can order optional larger brackets for mounting the chassis in a 19-inch SBC rack.
You can mount the router in the following ways:
- Center-front mounting—Brackets attached in the center front of the chassis with only the front panel facing forward.
- Center-back mounting—Brackets attached in the center back of the chassis with only the back panel facing forward.
- Front mounting—Brackets attached at the front of the chassis with the front panel facing forward.
- Back mounting—Brackets attached at the back of the chassis with the back panel facing forward.
Attaching Rack-Mount Brackets to Cisco 2901 Routers
For the Cisco 2900 series routers use four of the supplied number-8 Phillips flat-head screws to attach the long side of each bracket to the router. For the Cisco 3900 series routers use four of the supplied number-6 Phillips flat-head screws to attach the long side of each bracket to the router.
shows how to attach the brackets to the sides of the router with the front panel forward.
Figure 3-1 Bracket Installation for Front Mounting

Bracket Installation for Back Mounting shows how to attach the brackets to the sides of the router with the back panel forward.
Figure 3-2 Bracket Installation for Back Mounting

Bracket Installation for Center Mounting shows how to attach the brackets to the sides of the router with center mounting.
Figure 3-3 Bracket Installation for Center Mounting

Rack-Mounting the Chassis
If you are planning to rack-mount the router, do so before making network and power connections. If you need to install network modules or interface cards, you can do so either before or after rack-mounting the router. Ideally, you would install modules and interface cards when you have the best access to the rear panel of the router. Internal modules, such as advanced integration modules (AIMs) or packet voice data modules (PVDMs), should be installed prior to rack-mounting.
Cisco 2811, Cisco 2821, and Cisco 2851 routers can be installed in 19 (48.26-cm)- and 23-inch (58.42-cm) racks. Cisco 2801 routers can be installed only in 19-inch racks, and cannot be center mounted. Use the standard brackets shipped with the router for mounting the chassis in a 19-inch rack; you can order optional larger brackets for mounting the chassis in a 23-inch rack.

Note Brackets for 23-inch (58.42-cm) equipment racks are not available for Cisco 2801 routers.
You can mount the router in the following ways:
•Center mounting—Brackets attached in the center of the chassis with only the front panel facing forward. (This option is not available on Cisco 2801 routers.)
•Front mounting—Brackets attached at the front of the chassis with the front panel facing forward.
•Rear mounting—Brackets attached at the rear of the chassis with the rear panel facing forward.
The brackets are shown in Figure 5, Figure 6, and Figure 7.
Figure 6 Rack-Mounting Brackets for Cisco 2811 Routers

Attaching Rack-Mount Brackets to Cisco 2811, Cisco 2821, and Cisco 2851 Routers
Attach the mounting brackets to the router chassis as shown in Figure 9 through Figure 11, using the screws provided.

Caution

Attach the second bracket to the opposite side of the chassis. Use a number 2 Phillips screwdriver to install the bracket screws.

Caution

Figure 9 Bracket Installation for Front Mounting

Figure 10 Bracket Installation for Rear Mounting

Figure 11 Bracket Installation for Center Mounting with Front Panel Forward

Installing the Router in a Rack
After you have attached the brackets to the router chassis, use the screws provided with the rack to install the chassis in the rack. (See Figure 12.)

Tip Start the lower pair of screws first, and rest the brackets on the lower screws while you insert the upper pair of screws.

Tip The screw slots in the brackets are spaced to line up with every second pair of screw holes in the rack. When the correct screw holes are used, the small threaded holes in the brackets line up with unused screw holes in the rack. If the small holes do not line up with the rack holes, you must raise or lower the brackets to the next rack hole.
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Caution

Figure 12 Mounting the Chassis in a Rack (Typical)

Attaching Optional Cable Management Bracket
The optional cable management bracket provides attachment points for organizing and routing cables. On brackets for the Cisco 2801 and Cisco 2811 routers, attach the cable management bracket to the left or right rack-mount bracket using the screw provided, as shown in Figure 13 and Figure 14. On brackets for 2-rack-unit-high Cisco 2821 and Cisco 2851 routers, you can attach the cable management bracket to either the upper or lower threaded hole on either the left or right rack-mount brackets using the
screw provided.
Figure 14 Attaching the Optional Cable Management Bracket to a Cisco 2811, 2821, or 2851 Router

Chassis Grounding
After the router is installed, you must connect the chassis to a reliable earth ground. For the chassis ground connection procedures, see the "Installing the Chassis Ground Connection" section.