N Commands
This chapter describes the system management commands that begin with N.
ntp
To configure the Network Time Protocol (NTP) peers and servers for the switch, use the ntp command. To remove configured peers and servers, use the no form of this command.
ntp { peer hostname | server hostname } [ prefer ] [ use-vrf vrf-name ]
no ntp { peer hostname | server hostname }
Syntax Description
(Optional) Specifies this peer/server as the preferred peer/server. |
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(Optional) Specifies the virtual routing and forwarding (VRF) used to reach this peer/server. |
Command Default
Command Modes
Command History
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Usage Guidelines
Examples
This example shows how to form a server association with a server:
This example shows how to form a peer association with a peer:
This example shows how to delete an association with a peer:
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ntp abort
To discard the Network Time Protocol (NTP) Cisco Fabric Services (CFS) distribution session in progress, use the ntp abort command.
Syntax Description
Command Default
Command Modes
Command History
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Examples
This example shows how to discard the NTP CFS distribution session in progress:
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ntp authenticate
To prevent the system from synchronizing with unauthenticated, unconfigured network peers, use the ntp authenticate command. Use the no form of this command to allow synchronization with unauthenticated, unconfirmed network peers.
Syntax Description
Command Default
Command Modes
Global configuration mode (config)
network-admin
network-operator
vdc-admin
vdc-operator
Command History
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Usage Guidelines
If the system has been configured with the ntp passive, ntp broadcast client, or ntp multicast client commands, when NTP receives an incoming symmetric active, broadcast, or multicast packet, it can set up an ephemeral peer association in order to synchronize with the sender.
If ntp authenticate is specified, when a symmetric active, broadcast, or multicast packet is received, the system will not synchronize to the peer unless the packet carries one of the authentication keys specified in the ntp trusted-key global configuration command.
To prevent synchronization with unauthorized network hosts, ntp authenticate should be specified any time ntp passive, ntp broadcast client, or ntp multicast client has been specified unless other measures, such as the ntp access-group command, have been taken to prevent unauthorized hosts from communicating with the NTP service on the device.
Make sure that you are in the correct virtual device context (VDC). To change the VDC, use the switchto vdc command.
This command does not require a license.
Note
This command does not authenticate peer associations configured via the ntp server and ntp peer commands. To authenticate ntp server and ntp peer associations, specify the key keyword.
Examples
This example shows how to enable NTP authentication:
switch(config)# ntp authenticate
This example shows how to disable NTP authentication:
Related Commands
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Specifies one or more keys that a time source must provide in its NTP packets in order for the device to synchronize to it. |
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ntp commit
To apply the pending configuration pertaining to the Network Time Protocol (NTP) Cisco Fabric Services (CFS) distribution session in progress in the fabric, use the ntp commit command.
Syntax Description
Command Default
Command Modes
Command History
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Examples
This example shows how to commit changes to the active NTP configuration:
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ntp distribute
To enable Cisco Fabric Services (CFS) distribution for Network Time Protocol (NTP), use the ntp distribute command. To disable this feature, use the no form of this command.
Syntax Description
Command Default
Command Modes
Command History
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Usage Guidelines
Before distributing the Fibre Channel timer changes to the fabric, the temporary changes to the configuration must be committed to the active configuration using the ntp commit command.
Examples
This example shows how to distribute the active NTP configuration to the fabric:
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Commits the NTP configuration changes to the active configuration. |
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ntp sync-retry
To retry synchronization with the configured Network Time Protocol (NTP) servers, use the ntp sync-retry command.
Syntax Description
Command Default
Command Modes
Command History
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Examples
This example shows how to retry synchronization with the configured NTP servers:
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