Extreme Networks BlackDiamond 8806, Hardware Installation Manual

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BlackDiamond 8800 Series Switches Hardware Installation Guide
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CAUTION
Do not attempt to combine modules from the BlackDiamond 8800 series and BlackDiamond 12800 series product
lines. When a BlackDiamond 8800 series switch is running, ExtremeXOS software will not recognize an installed
BlackDiamond 12800 series module.
Management Switch Modules (MSM)
The following MSMs are available for the BlackDiamond 8800 series switches:
●
8500-MSM24
●
8800 series MSMs
■
MSM-G8X
■
MSM-48
■
MSM-48c
●
8900-MSM128
The MSMs provide the active switching fabric and CPU control subsystem for the switch. One MSM is
required for switch operation; however, adding a second MSM to the chassis increases reliability and
throughput.
A compact flash slot allows you to insert an external compact flash memory card. (See “External
Compact Flash Memory Card” on page 14 for more information about Extreme Networks-supported
compact flash cards.)
Redundant MSM Activity
The BlackDiamond 8800 series switches can run with a single MSM installed. When you install an
additional MSM, one MSM operates as the primary MSM and the other becomes the backup
(secondary) MSM. The primary MSM is responsible for upper-layer protocol processing and system
management functions. Packet handling is distributed among the CPUs of all installed MSMs.
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 switch boots with two MSMs installed, the MSM in the lower-numbered slot becomes the
primary MSM. In the BlackDiamond 8810 switch this is slot 5; in the BlackDiamond 8806 switch, this
is slot 3.
●
When a switch boots with a single MSM (regardless of the slot position), it is selected as the primary
MSM.
If a second MSM is added to the switch after it has been powered up, the added MSM becomes the
backup MSM. MSMs that operate as backup MSMs can be inserted and removed without disrupting
network services.
●
If you remove the primary MSM while the switch is operating, the backup MSM performs a soft
reset and then becomes the primary MSM.
For example, in a BlackDiamond 8810 switch with a primary MSM in slot 5 and a backup MSM in
slot 6, if you remove the primary MSM from slot 5, the backup MSM in slot 6 becomes the primary
MSM.