Dell S4820T Configuration Manual page 398

• Automatic and Manual RPM Failover
• Support for RPM Redundancy by Dell Networking OS Version
• RPM Synchronization
Boot the Chassis with a Single RPM
You can boot the chassis with one RPM and later add a second RPM, which automatically becomes the
standby RPM.
Dell Networking OS displays the following message when the standby RPM is online.
%RPM-2-MSG:CP0 %POLLMGR-2-ALT_RPM_STATE: Alternate RPM is present
%IRC-6-IRC_COMMUP: Link to peer RPM is up
%RAM-6-RAM_TASK: RPM1 is in Standby State.
Boot the Chassis with Dual RPMs
When you boot the system with two RPMs installed, the RPM in slot R0 is the primary RPM by default.
Both RPMs must be running the same version of Dell Networking OS.
To configure either RPM to be the primary after the next chassis reboot, use the redundancy primary
command from CONFIGURATION mode.
Version Compatibility Between RPMs
In general, the two RPMs should have the same Dell Networking OS version. However, Dell Networking
OS tolerates some degree of difference between the two versions, as described in the following table. To
view the configuration loaded on each RPM, use the show redundancy command, as shown in the
example in Automatic and Manual RPM
Table 30. Mismatch Condition Behaviors
Mismatch Condition
Different Dell Networking OS
versions with only the first two
digits matching.
Different Dell Networking OS
versions with the first two digits
not matching.
Different Dell Networking OS
versions with only the first three
digits matching.
Example of Dell Networking OS Version Incompatibility Error
************************************************
*
398
Failover.
Example
Primary: 7.4.2.0
Standby: 7.4.1.0
Primary: 7.6.1.0
Standby: 7.5.1.0
Primary: 7.4.2.0
Standby: 7.4.2.1
Behavior
The link to the standby RPM is up
and Dell Networking OS block
syncs only the startup-config.
The failover type is warm
upgrade. Dell Networking OS
displays the following message.
The link to the standby RPM is
down and the standby RPM is in a
boot loop. Dell Networking OS
displays the second message and
a boot fail prompt.
The link to the peer RPM is up
and Dell Networking OS
performs a complete block sync.
The failover type is hot failover.
Dell Networking OS displays the
following message.
High Availability (HA)