Juniper MX2010, Hardware Manual

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MX2010 Component Redundancy
A fully configured router is designed so that no single point of failure can cause the entire system to fail.
Only a fully configured router provides complete redundancy. All other configurations provide partial
redundancy. The following major hardware components are redundant:
•
Host subsystem—The host subsystem consists of a combined Control Board and Routing Engine (CB-RE)
functioning together. The router can have one or two host subsystems. If two host subsystems are
installed, one functions as the master and the other functions as the backup. If the master host subsystem
(or either of its components) fails, the backup can take over as the master.
•
DC power system—The MX2010 DC power system is made up of three components: nine power supply
modules (PSMs), two power distribution modules (PDMs), and a power midplane (PMP). The power
system distributes power from a pool of 22.5 KW (20 KW for PSM non-redundant and 2.5 KW reserved
for PSM redundancy). This pool provides power to ten line-card slots, four fan trays and critical FRUs.
These critical FRUs consist of two CB-REs and eight SFBs located in the top portion of the chassis.
•
DC power feed redundancy—The MX2010 router power system is feed redundant. Each PSM can be
connected to two separate feeds from different sources that are used to provide feed redundancy. There
are two PDMs per power subsystem that carry nine feeds each. Users should connect feeds from one
power source to one PDM and feeds from the other power source to the second PDM of the power
subsystem (see Figure 5 on page 14 ).
Figure 5: DC Power System Feed Redundancy
g007087
PDM 0
(feed A)
PDM 1
(feed B)
PSM
0
PSM
1
PSM
8
Each PSM has a set of two DIP switches located on the faceplate. These DIP switches are used to indicate
whether a user wants to connect one feed to the power system, two feeds, or none. These DIP switches
provide critical information to the power management system to help generate alarms in case of a feed
failure or a wrong connection. Each PDM has an LED per feed indicating whether the feed is active or
not, or whether the feed is connected properly. See “MX2010 DC Power Supply Module (-48 V)
Description” on page 116 .
•
AC power system—The MX2010 supports connection of a three-phase AC power system. There are
two types of three-phase power systems: the three-phase delta and three-phase wye. The AC power
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