BlackDiamond 12800 Series MSMs
BlackDiamond 12800 Series Switches Hardware Installation Guide 21
Redundant MSM Activity (BlackDiamond 12804 Switch)
The BlackDiamond 12804 switch can operate with a single MSM installed, providing full bandwidth
with this single MSM. When you install a second MSM, one of the MSMs operates as the primary, and
the other becomes the secondary or backup.
The primary MSM is responsible for upper-layer protocol processing and system management
functions. The MSMs in the BlackDiamond 12804 switch are not load sharing. MSM(A) or MSM(B)
handles packets while the other MSM is idle.
When you save the switch configuration, it is saved to all MSMs.
Selection of the primary MSM occurs automatically. The following examples describe the selection
process:
●When a BlackDiamond 12804 switch boots with two MSMs installed, the MSM in slot 3/A becomes
the primary.
If a switch is operating with one MSM and a second MSM is added to the switch after it has been
powered up, the added MSM becomes the secondary. MSMs that operate as secondary, or backup,
MSMs can be inserted and removed without disrupting network services.
●If you remove the primary MSM while the switch is operating, the secondary MSM performs a soft
reset and then becomes the primary MSM.
For example, if you have a BlackDiamond 12804 switch with a primary MSM in slot 3/A and a
secondary MSM in slot 4/B, and you remove the primary MSM from slot 3/A, the secondary, or
backup, MSM in slot 4/B becomes the primary.
MSM LEDs
Tabl e 5 describes the LED activity on the BlackDiamond 12800 series MSMs.

Table 5: BlackDiamond 12800 Series MSM LEDs

LED Color Meaning
SYS Green blinking
Amber blinking
Normal operation.
Diagnostic tests are running on the module. The LED resets if the
diagnostics are terminated. The LED returns to blinking amber if
another diagnostic test is started.
Amber steady Diagnostic failure has occurred.
Off Switch is not receiving power.
MSTR Green steady Module is operating as primary MSM.
Amber Module is operating as secondary, or backup, MSM.
Green blinking Power-on self-test (POST) is running.
Off Normal operation for diagnostics.
ERR Amber A critical software error has been logged since power-up.
Off Normal operation.
ENV Green Environment (temperature, fan, power supply) is operating properly.
Amber Environmental failure has occurred.