Verifications Of Requirements; Upgrade Setup - Juniper SERVICE AVAILABILITY - CONFIGURATION GUIDE V 11.1.X Configuration Manual

JUNOSe 11.1.x Service Availability Configuration Guide
Table 13: Router Response to Undesirable Events During the Upgrade
Phase (continued)

Verifications of Requirements

Because some time may have passed since unified ISSU verified the requirements
for the upgrade during the initialization phase, unified ISSU reverifies all the same
conditions.
Unified ISSU also verifies that no CLI configuration sessions are open, that no scripts
or macros are running, and that any SNMP requests or CLI commands in progress
complete within 5 seconds.
If any of the required conditions are not met, the CLI either exits the command with
an error message or provides an informative message and prompts you to proceed
or halt.
When all the conditions are met, the CLI prompts you to proceed. If you continue,
then you can subsequently halt the upgrade only by reloading the router. If you exit
the command, the router remains in the unified ISSU initialized state.

Upgrade Setup

At this stage all the preconditions have been met. The unified ISSU process shuts
down all management interfaces to the router in order to prevent changes in the
configuration.
Final preparation for the upgrade phase includes the following actions:
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Unified ISSU Upgrade Phase Overview
Event Router Action
An application that This event can take place only before the issu start command is
does not support issued, because that command disables CLI configuration commands.
unified ISSU is When you issue the issu start command, after configuring such an
configured. application, the command exits and generates an error message.
SNMP The SNMP agent generates a juniSystemIssuStateChange trap with
juniSystemIssuState set to upgrading to indicate that the final phase of the
operation has begun. When the trap is issued with this state value, the SNMP
agent stops accepting any new SNMP gets or sets and does not issue any further
traps.
CLI Most CLI commands are disabled. Only reload, show issu, and show
version commands are available to you until the service restoration phase
completes. These commands are available on the console and are not available
to Telnet sessions.
External events Externally created events from sources other than the CLI are
ignored. These events typically come from user connections, RADIUS servers,
SRC software and SDX software, and SNMP, and include login requests, COA
requests, multicast join requests, packet mirroring requests, and so on. Logout
requests are cached and processed at a later stage.