IronPort - advanced configuration guide

Chapter 8 Centralized Management
Disconnect/Reconnect
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A machine may be disconnected from a cluster. Occasionally, you may intend to deliberately disconnect
the machine, for example, because you are upgrading the machine. A disconnect could also occur by
accident, for example, due to a power failure or other software or hardware error. A disconnect can also
occur if one appliance attempts to open more than the maximum number of SSH connections allowed in
a session. A machine that is disconnected from a cluster can still be accessed directly and configured;
however, any changes made will not be propagated to other machines within the cluster until the
disconnected machine becomes reconnected.
When a machine reconnects to the cluster, it tries to reconnect to all machines at once.
In theory, two machines in a cluster that are disconnected could commit a similar change to their local
databases at the same time. When the machines are reconnected to the cluster, an attempt will be made
to synchronize these changes. If there is a conflict, the most recent change is recorded (supersedes any
other changes).
During a commit, the appliance checks every variable that is being changed. The commit data includes
version information, sequence identification numbers, and other information that can be compared. If
the data you are about to change is found to be in conflict with previous changes, you will be given the
option to discard your changes. For example, you might see something like this:
(Machine mail3.example.com)> clustercheck
This command is restricted to "cluster" mode. Would you like to switch to "cluster"
mode? [Y]> y
Checking Listeners (including HAT, RAT, bounce profiles)...
Inconsistency found!
Listeners (including HAT, RAT, bounce profiles) at Cluster enterprise:
mail3.example.com was updated Mon Sep 12 10:59:17 2005 PDT by 'admin' on
mail3.example.com
test.example.com was updated Mon Sep 12 10:59:17 2005 PDT by 'admin' on
mail3.example.com
How do you want to resolve this inconsistency?
1. Force entire cluster to use test.example.com version.
2. Force entire cluster to use mail3.example.com version.
3. Ignore.
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Cisco IronPort AsyncOS 7.6 for Email Advanced Configuration Guide
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