Reloading The Secondary Line Module In Response To Failures; Disabling The Primary And Secondary Line Module Slots; Reloading The Router When Line Modules Enabled For Ha Are Installed; Removing Ioas Without Powering Down From Line Modules - Juniper JUNOSE SOFTWARE FOR E SERIES 11.3.X - SERVICE AVAILABILITY CONFIGURATION GUIDE 2010-10-08 Configuration Manual

JunosE 11.3.x Service Availability Configuration Guide

Reloading the Secondary Line Module in Response to Failures

Disabling the Primary and Secondary Line Module Slots

Reloading the Router When Line Modules Enabled for HA Are Installed

Removing IOAs Without Powering Down from Line Modules

Cold and Warm Switchovers of Line Modules In a High Availability Pair

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secondary line module takes over by recovering all the applications running on the primary
module to a stable state. After the secondary module takes over, traffic starts flowing
through the secondary module. The FC and IOAs on the faulty line module are cold booted
along with the IC. When you use the slot disable command for a slot that contains a line
module, you disable only the line module; you do not disable the line module and IOAs
associated with it.
When a software fault occurs on the secondary line module or if you enter the slot disable
or reload slot commands for the slot in which the secondary line module is installed, the
secondary line module undergoes a cold boot. After the secondary module becomes
operational, the reloaded module continues to function as the secondary line module.
Any core dumps that are generated on the faulty line module are sent to the SRP module,
which is the same behavior as the one that occurs when a line module that is not
configured for HA resets. When you use the slot disable command for a slot that contains
a line module, you disable only the line module; you do not disable the line module and
IOAs associated with it.
If you specify the slot erase command on the primary line module to delete the
configuration of the module in the selected slot before you install a different type of
module, both the primary and secondary line modules are cold booted and line module
high availability is disabled after the modules become operational again. If you enter the
slot erase command on the secondary line module, only that module is cold booted and
line module high availability is disabled.
If you enter the reload command on the router to restart the device with the currently
available configuration, the previously configured roles of the primary and secondary line
modules are preserved. SRP modules reload all line modules and restart form saved
configuration files. However, any failure of the primary line module to become operational
after the prescribed timeout duration causes the secondary module to take over as the
primary.
Removal of an IOA from the primary line module without powering down the IOA does
not trigger line module switchover. Removal of an IOA from the secondary line module
does not cause the module to be cold started. In both such scenarios, we recommend
that you perform a hot-swap of the IOA in a managed environment when high availability
is configured on the line module pair.
Cold switchover of the line module results in the same behavior as the system operations
that are witnessed with line module redundancy configured on a router. With both these
features, all the existing subscriber sessions are lost during the switchover.
When a warm switchover of the line module in a high availability pair occurs, subscriber
sessions are not lost during the switchover.
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