Contents

Configuring graceful insertion and removal 1

About graceful insertion and removal 1

Restrictions and guidelines: GIR configuration· 1

Placing the device in maintenance mode· 2

Changing the device back to normal mode· 3

Display and maintenance commands for GIR· 3

Configuring graceful insertion and removal

About graceful insertion and removal

Graceful insertion and removal (GIR) enables you to gracefully isolate the device from the network for device maintenance or upgrade. GIR minimizes service interruption by instructing the affected protocols (for example, routing protocols) to isolate the device and switch over to the redundant path. You do not need to configure graceful switchover protocol by protocol.

GIR modes

The device can operate in either of the following GIR modes:

·     Normal mode—The device can forward traffic.

·     Maintenance mode—The device is gracefully placed out of service for maintenance or upgrade purposes. In this mode, the device cannot forward traffic.

How GIR works

After you place the device in maintenance mode, GIR instructs each affected protocol (for example, BGP) to remove the device from the traffic path. Then, each protocol takes action as instructed to isolate the device and switch over to the redundant path.

To record the configuration before and after a GIR operation, GIR takes a snapshot of protocol data when the device enters maintenance mode and when the device changes back to normal mode. You can compare the snapshots to verify configuration data consistency for each protocol.

GIR supports the following protocols:

·     LACP.

·     BGP.

·     IS-IS.

·     OSPF.

·     OSPFv3.

For more information about how each protocol isolates the device, see its configuration guide.

GIR snapshots

GIR snapshots record the state and running data of the device in NETCONF format.

When the device enters maintenance mode, it generates a GIR snapshot named before_maintenance before each protocol switches over to the redundant path.

When the device returns to normal mode, it generates a GIR snapshot named after_maintenance immediately after all protocols insert the device back into the traffic path.

The device stores only the snapshots for the most recent GIR operation.

You can identify the configuration differences of the device before and after a GIR operation by comparing the two snapshots.

Restrictions and guidelines: GIR configuration

The device supports isolating routing and DRNI services but cannot ensure zero packet loss for DRNI services.

Placing the device in maintenance mode

About this task

Perform this task before you maintain or upgrade the device.

The device enters maintenance mode regardless of whether a protocol has failed in switchover. The failure of one protocol in switchover does not affect other protocols.

Restrictions and guidelines

To maintain configuration data consistency, do not modify the configuration for any affect protocols after you place the device in maintenance mode. If you modify the configuration of a protocol, the new configuration will overwrite the original configuration after the device changes back to normal mode.

Prerequisites

If the device is comparing snapshots, you must wait the comparison to end before you can change the GIR mode.

Procedure

1.     Verify that the system is stable.

display system stable state

The system is stable if the System State field displays Stable. For a successful GIR operation, you must make sure the system is stable.

2.     Enter system view.

system-view

3.     Place the device in maintenance mode.

gir system-mode maintenance

4.     If a protocol fails in switchover, use the following methods to identify and remove the issue:

¡     Remove the issue based on the error message.

¡     Compare the snapshots to identify configuration inconsistencies that might cause the issue.

Identify snapshot information:

display gir snapshot

Compare the snapshots:

display gir snapshot compare snapshot1-name snapshot2-name [ verbose ]

5.     Verify that no traffic traverses the device before you maintain or upgrade the device.

display counters

This command is available in any view. This step prevents the packet loss that might occur because a protocol is slow or fails in switchover.

Changing the device back to normal mode

About this task

Perform this task after you maintain or upgrade the device.

The device changes back to normal mode regardless of whether a protocol has failed in switchover. The failure of one protocol in switchover does not affect other protocols.

Prerequisites

If the device is comparing snapshots, you must wait the comparison to end before you can change the GIR mode.

Before you change a DRNI system back to normal mode, execute the display drni mad verbose command to verify that no network interfaces are in DRNI MAD DOWN state. For more information about DRNI, see Layer 2—LAN Switching Configuration Guide.

Procedure

1.     Verify that the system is stable.

display system stable state

The system is stable if the System State field displays Stable.

2.     Enter system view.

system-view

3.     Change the device back to normal mode.

undo gir system-mode maintenance

4.     If a protocol fails in switchover, use the following methods to identify and remove the issue:

¡     Remove the issue based on the error message.

¡     Compare the snapshots to identify configuration inconsistencies that might cause the issue.

Identify the snapshot names:

display gir snapshot

Compare the snapshots:

display gir snapshot compare snapshot1-name snapshot2-name [ verbose ]

Display and maintenance commands for GIR

Execute display commands in any view.

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