User's Manual

Installing and Setting Up the CMC 41
The CMC is connected to the management network. All external access to
the CMC and iDRACs is accomplished through the CMC. Access to the
managed servers, conversely, is accomplished through network connections to
I/O modules (IOMs). This allows the application network to be isolated from
the management network.
If you have one chassis, connect the CMC, and the standby CMC if present,
to the management network. If you have more than one chassis, you can
choose between the basic connection, where each CMC is connected to the
management network, or a daisy-chained chassis connection, where the
chassis are connected in series and only one is connected to the management
network. The basic connection type uses more ports on the management
network and provides greater redundancy. The daisy-chain connection type
uses fewer ports on the management network but introduces dependencies
between CMCs, reducing the redundancy of the system.
Basic CMC Network Connection
For the highest degree of redundancy, connect each CMC to your
management network. If a chassis has just one CMC, make one connection
on the management network. If the chassis has a redundant CMC in the
secondary CMC slot, make two connections to the management network.
Each CMC has two RJ-45 Ethernet ports, labeled GB1 (the uplink port) and
STK (the stacking port). With basic cabling, you connect the GB1 port to the
management network and leave the STK port unused.
Daisy-chain CMC Network Connection
If you have multiple chassis in a rack, you can reduce the number of
connections to the management network by daisy-chaining up to four chassis
together. If each of four chassis contains a redundant CMC, by daisy-chaining
you reduce the number of management network connections required from
eight to two. If each chassis has only one CMC, you reduce the connections
required from four to one.
When daisy-chaining chassis together, GB1 is the uplink port and STK is the
stacking port. A GB1 port must connect to the management network or to the
STK port of the CMC in a chassis that is closer to network. The STK port
must only receive a connection from a GB1 port further from the chain or
network.