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Support for RPM Redundancy by Dell EMC Networking OS Version
Dell EMC Networking OS supports increasing levels of RPM redundancy (warm and hot) as described in the table below.
Table 36. Support for RPM Redundancy by Dell EMC Networking OS Version
Platform Failover Type Failover Behavior
S4820T Hot Failover Only the failed RPM reboots. All the
line cards and SFMs remain online. All
application tasks are spawned on the
secondary RPM before failover. The
running configuration is synchronized
at runtime so it does not need to be
reapplied during failover.
Synchronization between Management and Standby Units
Data between the Management and Standby units is synchronized immediately after bootup.
After the Management and Standby units have done an initial full synchronization (block sync), Dell EMC Networking OS only
updates changed data (incremental sync). The data that is synchronized consists of configuration data, operational data, state
and status, and statistics depending on the Dell EMC Networking OS version.
Configuring RPM Redundancy
To select a primary RPM, use the following command. The RPM in slot 0 is the primary RPM by default.
● Manually select the primary RPM.
CONFIGURATION mode
redundancy primary
Dell#show running-config redundancy
!
redundancy auto-failover-limit count 3 period 60
redundancy auto-synchronize full
redundancy primary rpm0
Dell#
To view which RPM is the primary, use the show running-config redundancy command from EXEC Privilege mode, as
shown in the example in the Forcing an RPM Failover.
Forcing a Stack Unit Failover
To force a Stack unit failover, use the following command.
Use this feature when you are replacing a stack unit and when you are performing a warm upgrade.
● To trigger a stack unit failover.
EXEC Privilege mode
redundancy force-failover stack-unit
Dell#redundancy force-failover stack-unit
System configuration has been modified. Save? [yes/no]: yes
Proceed with Stack-unit hot failover [confirm yes/no]:yes
Dell#
High Availability (HA)
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