Table of Contents
Advertisement
JunosE 11.3.x Service Availability Configuration Guide
Related
Documentation
Stateful SRP Switchover States
38
When stateful SRP switchover is enabled, an SRP switchover keeps line modules up and
forwarding data, and the newly active SRP module continues from the point of switchover.
By using transaction-based mirroring instead of file synchronization, high availability
mode keeps the standby SRP module synchronized with the active SRP module. Mirroring
occurs from memory on the active SRP module to memory on the standby SRP module
by way of transactions. When a transaction is committed on the active SRP module, the
data associated with the transaction is sent to the standby SRP module.
In high availability mode:
The contents of the NVS in the primary and standby SRP modules remain synchronized.
NOTE: Configuration files are always synchronized. Nonconfiguration files
are synchronized when the disable-autosync command has not been
configured; this is the default case. When the disable-autosync command
has been configured, nonconfiguration files are not synchronized.
If a switchover occurs:
The standby SRP module warm-restarts using the mirrored data to restore itself to
the state of the system before the switchover.
During the warm restart:
User connections remain active, and forwarding continues through the chassis.
New user connection attempts during switchover are denied until switchover is
complete.
New configuration changes are prevented until switchover is complete (or after
5 minutes).
NOTE: If the switchover does not finish within 5 minutes, the SRP
module cancels the operation and reenables CLI configuration.
Stateful SRP Switchover States on page 38
disable-autosync
redundancy
mode
The SRP progresses through various high availability states. These states are illustrated
in Figure 4 on page 39.
Copyright © 2010, Juniper Networks, Inc.
Advertisement
Table of Contents
