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Home Documentation Junos OS Junos CLI Reference CLI Reference R

Junos CLI Reference

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Junos CLI Reference
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request chassis cb

date_range 16-Jan-25
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Syntax

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request chassis cb (offline | online) slot slot-number

Syntax (QFabric System)

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request chassis cb  (offline | online) interconnect-device name slot slot-number
<interconnect-device name slot slot-number (offline | online)>

Syntax (EX9253 Switches)

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request chassis cb  (offline | online) name slot slot-number

request chassis cb (PTX10008 Router)

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user@host> request chassis cb offline slot 1
Offline initiated, use "show chassis environment cb" to verify

Output

The following error message is displayed when you try to offine a slot when the related node is online.

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root@re0-re0> request chassis cb slot 1 offline

Error: CB offline is not allowed, when node is in online state.
Try to offline the node using "request node offline [node]"

Description

Control the operation of the Control Board (CB).

Options

offline

Take the Control Board offline.

Note:

On a QFabric system, to bring the backup Control Board on a QFX3008-I Interconnect device offline, issue the request chassis cb slot backup-slot-number offline command.

Note:

Only backup Control Board can be turned offline or online. To turn a Control Board offline or to bring it back online, the Routing Engine should be turned offline first.

online

Bring the Control Board online.

interconnect-device name

(QFabric systems only) (Optional) Bring the QFX3008-I Interconnect device Control Board either offline or online:

slot slot-number

The following options can be configured for CB slots:

  • offline —Take the CB slot offline.

  • online — Bring the CB slot online.

Control Board slot number:

  • M320 router—Replace slot-number with a value from 0 through 1.

  • MX480/MX240 routers—Replace slot-number with a value from 0 through 1.

  • MX960 router—Replace slot-number with a value from 0 through 2.

  • MX2020, MX2010, and MX2008 routers—Replace slot-number with 0 or 1.

  • EX8208 switch—Replace slot-number with a value from 0 through 2.

  • EX8216 switch—Replace slot-number with a value from 0 through 1.

  • QFabric System—Replace slot-number with a value from 0 through 1.

Required Privilege Level

maintenance

Output Fields

When you enter this command, you are provided feedback on the status of your request.

Sample Output

request chassis cb

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user@host> request chassis cb offline slot 1
 
Backup CB 1 cannot be set offline, backup RE is online

request chassis cb interconnect-device (QFabric System)

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user@switch> request chassis cb interconnect-device
interconnect1 offline slot 1
Backup CB 1 cannot be set offline, backup RE is online

request chassis cb (MX2020 Router)

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user@host> request chassis cb offline slot 1
Backup CB 1 cannot be set offline, backup RE is online

request chassis cb (MX2010 Router)

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user@host> request chassis cb offline slot 1
Backup CB 1 cannot be set offline, backup RE is online

request chassis cb (MX2008 Router)

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user@host>request chassis cb offline slot 1
Backup CB 1 cannot be set offline, backup RE is online

request chassis cb (MX10003 Router)

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user@host>request chassis cb online slot 1
CB 1 appears to be online already

request chassis cb (EX9253 Switch)

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user@switch>request chassis cb offline slot 1
Offline initiated, use "show chassis environment cb" to verify

request chassis cb (ACX7509)

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user@host>request chassis cb offline slot 1
Offline initiated
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user@host>request chassis cb online slot 1
Online initiated

Usage

When request chassis cb slot 1 offline, is configured before the node is made offline, the following error Error: CB offline is not allowed, when the node is online state. Try to offline the node using "request node offline node is displayed.

Platform-Specific request chassis cb Behavior

Use Feature Explorer to confirm platform, and release support for specific features.

Use the following table to review platform-specific behaviors for your platform:

Table 1:

Platform

Difference

Junos OS Evolved device with dual Routing and Control Boards (RCBs)

After initiating a node halt, you must wait 1 minute before doing Control Board (CB) offline. This delay ensures system stability. If you try to offline a CB within this period, the system displays the following error message:

request chassis cb slot 1 offline
Error: CB offline is not allowed now, Try after sometime

Release Information

Command introduced before Junos OS Release 7.4.

Related Documentation

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