Configuring an IPv6 discovery prefix

Configure the discovery prefixes to send in router advertisement.

Before you begin

Change the VRF instance as required to configure an IPv6 discovery prefix on a specific VRF instance. Not all parameters are configurable on non-default VRFs.

About this task

Hosts on the link use router advertisements to perform IPv6 autoconfiguration. The discovery prefix controls what IPv6 addresses to autoconfigure and how long they are valid.

You can also configure an IPv6 interface for a brouter port through the Edit > Port > IPv6 navigation path, and for a VLAN through the VLAN > VLANs > Basic > IPv6 navigation path. This procedure uses the main IPv6 navigation path where you can configure both types of interfaces.

Procedure

In the navigation tree, expand the following folders: Configuration > IPv6.
Click IPv6.
Click the Discovery Prefix tab.
Click Insert.
Beside the Interface field, click Port or VLAN.
Select a port or VLAN.
Click OK.
Specify the prefix and prefix length.
Click Insert.
Click Apply.

Discovery Prefix Field Descriptions

Use the data in the following table to use the Discovery Prefix tab.


Name	Description
Interface	Shows a read-only value that indicates an IPv6 interface. For the brouter port, it is the ifindex of the port and, in the case of the VLAN, it is the ifindex of the VLAN.
Prefix	Configures the prefix to create an IPv6 prefix entry as either advertised or suppressed.
PrefixLen	Configures the mask to create an IPv6 address in the IPv6 interface table.
VLanId	Specifies the VLAN ID in the range of 1 to 4059. By default, VLAN IDs 1 to 4059 are configurable and the system reserves VLAN IDs 4060 to 4094 for internal use. On switches that support the vrf-scaling and spbm-config-mode boot configuration flags, if you enable these flags, the system also reserves VLAN IDs 3500 to 3998. VLAN ID 1 is the default VLAN and you cannot create or delete VLAN ID 1.
UseDefaultVal	Specifies one included value to use the default value, or use all bits to configure all options to their default value.
ValidLifetime	Configures the valid lifetime in seconds that indicates the length of time this prefix is advertised. The default is 2592000. A valid lifetime is the length of time of the preferred and depreciated state of an autoconfiguration address. The preferred lifetime value must be less than the valid lifetime value. If you must configure the valid lifetime value to a value lower than the current preferred lifetime, you must lower the preferred lifetime value first.
PreferedLifetime	Configures the preferred lifetime in seconds that indicates the length of time this prefix is advertised. The default value is 604800. The preferred lifetime is the length of time for the tentative, preferred, and depreciated state of an autoconfiguration address. The preferred lifetime value must be less than the valid lifetime value. If you must configure the valid lifetime value to a value lower than the current preferred lifetime, you must lower the preferred lifetime value first.
Infinite	Configures the prefix valid lifetime so it never expires. The default is false.
OnLinkFlag	Configures the prefix for use when determining if a node is online. This value is placed in the L-bit field in the prefix information option. It is a 1-bit flag. The default is true.
AutoFlag	Configures the prefix for use as the autonomous address configuration. This value is placed in the autoflag field in the prefix information option. It is a 1-bit flag. The default is true.
AddressEui	Configures the EUI address. Use an EUI-64 interface ID in the address field. If enabled, use EUI, or use EUI-64 and the complement Universal/Local (U/L) bit. This operation provides for both gloal and link-local addresses. After you create the entry, you cannot modify this value. This value is valid for use only when the PrefixLength is 64 or less. The default is eui-not-used. If you select eui-not-used, this configuration creates an IPv6 ND prefix but no associated IPv6 address on the router. IF you select either eui-used-with-ul-complement or eui-used-without-ul-complement, an associated IPv6 adress is created by concatenating the specified prefix with the EUI-64 interface ID.
NoAdvertise	Configures if the prefix is included in the router advertisement. Select true to not include the prefix in the router advertisement. The default is false.