KB.15.15

Prefix Advertised

Lists the prefix and prefix size (number of leftmost bits in an address) originating

with the indicated router.

Valid Lifetime

The total time the address is available, including the preferred lifetime and the

additional time (if any) allowed for the address to exist in the deprecated state.

See “Valid lifetime” (page 28).

Preferred Lifetime

The length of time during which the address can be used freely as both a source

and a destination address for traffic exchanges with other devices. See

“Preferred lifetime” (page 28).

On/Off Link

Indicates whether the entry source is on the same VLAN as is indicated in the

Interface field.

Example 11 (page 28) indicates that the switch is receiving router advertisements from a single

router that exists on VLAN 10.

Example 11 show IPv6 routers output

HP Switch(config)# show ipv6 routers

IPv6 Router Table Entries

Router Address : fe80::213:c4ff:fedd:14b0

Preference : Medium

Interface : VLAN10

MTU : 1500

Hop Limit : 64

Valid Preferred On/Off

Prefix Advertised Lifetime(s) Lifetime(s) Link

-------------------------- ------------ ------------ -------

2001:db8:a03:e102::/64 864000 604800 Onlink

Address lifetimes

Every configured IPv6 unicast address has a lifetime setting that determines how long the address

can be used before it must be refreshed or replaced. Some addresses are set as "permanent" and

do not expire. Others have both a "preferred" and a "valid" lifetime that specify the duration of

their use and availability.

Preferred lifetime

This is the length of time during which the address can be used freely as both a source and a

destination address for traffic exchanges with other devices. This time span is equal to or less than

the valid lifetime also assigned to the address. If this time expires without the address being

refreshed, the address becomes deprecated and should be replaced with a new, preferred address.

In the deprecated state, an address can continue to be used as a destination for existing

communication exchanges but is not used for new exchanges or as a source for traffic sent from

the interface. A new, preferred address and its deprecated counterpart both appear in the show

ipv6 vlan vid output as long as the deprecated address is within its valid lifetime.

Valid lifetime

The valid lifetime, which is the total time the address is available, is equal to or greater than the

preferred lifetime. The valid lifetime enables communication to continue for transactions that began

28 IPv6 Addressing Configuration