Juniper JUNOS, Руководство по эксплуатации сети

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Manually Configuring Master and Backup Routing Engines
! 479
Chapter 36: Host Redundancy Overview
Step 3: Log In To Backup Routing Engine If graceful-switchover is Configured
If graceful-switchover is configured, the CLI command prompt will look as follows:
{backup}
user@host-re0>
{master}
user@host-re1>
With RE1 as master and RE0 as backup.
Action
If you are logged in to the master Routing Engine, log in to the backup Routing
Engine by using the following CLI command:
user@host> request routing-engine login other-routing-engine
Sample Output
user@host> request routing-engine login other-routing-engine
€Password: ########
{backup}
user@host-re0>
What It Means
You are now logged in to the backup Routing Engine in slot
RE0
.
Manually Configuring Master and Backup Routing Engines
For routers with two Routing Engines, you can configure which Routing Engine is
the master and which is the backup. By default, the Routing Engine in slot 0 is the
master (RE0) and the one in slot 1 is the backup (RE1).
To modify the default configuration, include the routing-engine statement at the [edit
chassis redundancy] hierarchy level:
[edit chassis redundancy]
routing-engine
slot-number
(master | backup | disabled);
slot-number
can be 0 or 1. To configure the Routing Engine to be the master, specify
the master option. To configure it to be the backup, specify the backup option. To
switch between the master and the backup Routing Engines, you must modify the
configuration and then activate it by issuing the
commit command.
The running state of a Routing Engine (master, backup, or disabled) is determined
by mastership election upon system boot.
! Master—If a Routing Engine is configured as master, it has full functionality. It
receives and transmits routing information, builds and maintains routing tables,
communicates with interfaces and Packet Forwarding Engine components, and
has full control over the chassis. Once a Routing Engine becomes master, it
resets the switch plane (SSB, SCB, and SFM) and downloads its current version
of the microkernel to the Packet Forwarding Engine components, guaranteeing
software compatibility.