3Com CoreBuilder 9000, User Manual

Page: 420 / 468

420 C
HAPTER
18: S
WITCH
R
EDUNDANCY
Identifying the
Active Switch Fabric
Module
While the CoreBuilder ® 9000 ATM Enterprise Switch boots, the ATM
Switch Fabric Module that is installed in slot 8 (of a 16-slot chassis) is
assigned as the Active Switch and the Switch Fabric Module that is
installed in slot 9 is designated as the Standby or Redundant Switch. After
the unit has booted, you can confirm that the Switch in slot 8 is the active
switch fabric module by the LMA command (1) SYS\(4) SWM\(1) DSS
or
by the Module Status LED as follows:
Active Switch: Active LED is lighted.
Redundant Switch: Stby (Standby) LED is lighted.
Conditions for
Switch-over to
Redundant Module
The switch-over to the redundant module occurs in the following
situations:
Removal of the active ATM Switch Fabric Module from the chassis.
Malfunction of the active ATM Switch Fabric Module.
Reboot of the active ATM Switch Fabric Module.
During the switch-over, the Redundant Switch becomes the active one.
All SVC connections fail during the switch-over. The connections must be
reestablished by the end station. The PVCS will be reestablished
immediately. (The approximate time of takeover is one minute.)
Access to the Redundant Switch is via the serial port only.
Switch Fabric
Module
Configuration
Database
Each switch fabric module contains a configuration database where the
switch configuration data is stored. For the Redundant Switch fabric
module to be ready to assume the role of the active switch, its
configuration database is updated from the active switch. This occurs in
the following situations:
When the standby switch is booted.
When the active switch configuration is changed.