Brocade Network OS Administrator’s Guide v4.1.1 - Manual (Page 59)

Management modules
Two management modules (MMs) provide redundancy and act as the main controller on the Brocade
VDX 8770-4 and VDX 8770-8 chassis. The management modules host the distributed Network OS that
provides the overall control plane management for the chassis. You can install a redundant
management module in slot M1 or M2 in any of the Brocade VDX 8770 chassis. By default, the system
considers the module in slot M1 the active management module and the module in slot M2 the
redundant, or standby, management module. If the active module becomes unavailable, the standby
module automatically takes over management of the system.
Each management module maintains its own copy of the configuration database. The startup
configuration is automatically synchronized with the other management module.
Brocade recommends that each management module (primary and secondary partition) should
maintain the same firmware version. For more information on maintaining firmware, refer to
Installing
and Maintaining Firmware on page 111.
Each management module has two Ethernet interfaces, Eth0 and Eth2. Eth0 is the management
interface and can be configured with an IP address. For more information on configuring the
management interface, refer to
Connecting to a switch on page 47.
HA failover
Warm-recovery HA failover is supported for both fabric cluster mode and logical chassis cluster mode.
Warm recovery includes the following behaviors:
• No data path disruption results for Layer 2 and FCoE traffic.
• All Layer 2 control protocol states are retained.
• The topology state and interface state are retained.
• All running configuration is retained (including the last accepted user configuration just before HA
failover).
• HA Management Module failover may result in data path and control path disruption for the Layer 3
protocol.
• Layer 3 configuration is replayed post-failover.
• During a warm recovery, the principal switch in a logical chassis cluster remains the principal switch.
After warm recovery, the principal switch reestablishes cluster management layer connection with
other switches and reforms the cluster.
• A secondary switch in a logical chassis cluster reestablishes cluster management layer connection
with the principal switch and rejoins the cluster after warm recovery.
• If you run a reload command on an active MM, the principal switch in a logical chassis cluster goes
into cold recovery and comes back up as a secondary switch.
• HA behavior during In-service software upgrades (ISSUs) is the same as for warm-recovery failover.
Support for In-service software upgrades
In-service software upgrades (ISSUs) are supported in Network OS 4.0.0 and later. An ISSU allows a
dual management module system to be upgraded non-disruptively and is invoked by entering the
firmware download command from the active management module.
ISSUs are supported in both fabric cluster mode and logical chassis cluster mode for the following
Network OS upgrade paths:
• 4.0.0 to 4.0.1
• 4.0.0 to 4.1.0
• 4.0.1 to 4.1.0
Management modules
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