Viewing the current IPv6 addressing configuration

Use these commands to view the status of the IPv6 configuration on the switch.

Syntax:

show ipv6

Lists the current, global IPv6 settings, and per-VLAN IPv6 addressing on the switch.

IPv6 Routing : Global setting and is not configured per-VLAN.

Default Gateway : Lists the IPv4 default gateway, if any, configured on the switch.It is a globally configured router gateway address and is not configured per-VLAN.

ND DAD : Indicates whether DAD is enabled (the default) or disabled. Using ipv6 nd dad-attempts 0 disables ND.

DAD Attempts : Indicates the number of neighbor solicitations the switch transmits per-address for duplicate (IPv6) address detection. Implemented when a new address is configured or when an interface with configured addresses (such as after a reboot). Default: 3; Range: 0–255 ms. A setting of “0” disables duplicate address detection. See Duplicate Address Detection (DAD).

VLAN Name : Lists the name of a VLAN statically configured on the switch.

IPv6 Status : For the indicated VLAN, shows whether IPv6 is disabled (the default) or enabled. See Configuring IPv6 addressing.

Address Origin :

Autoconfig : The address was configured using stateless address autoconfiguration (SLAAC). In this case, the interface identifier for global unicast addresses copied from the current link-local unicast address.

DHCP : The address is assigned by a DHCPv6 server. Addresses having a DHCP origin are listed with a 128-bit prefix length.

Manual : The address was statically configured on the VLAN.

IPv6 Address/Prefix Length : Lists each IPv6 address and prefix length configured on the indicated VLAN.

Address Status :

Tentative: DAD has not yet confirmed the address as unique, and it is not usable for sending and receiving traffic.

Preferred : The address has been confirmed as unique by DAD and usable for sending and receiving traffic. The Expiry time shown for this address by the show ipv6 vlan <vid> command output is the preferred lifetime assigned to the address. See Address lifetimes.

Deprecated : The preferred lifetime for the address has been exceeded, but there is time remaining in the valid lifetime.

Duplicate : Indicates a statically configured IPv6 address that is a duplicate of another IPv6 address that exists on another device belonging to the same VLAN interface. A duplicate address is not used.

The display below shows the output for a switch having IPv6 enabled on one VLAN. 

Switch# show ipv6

Internet (IPv6) Service

  IPv6 Routing    : Enabled
  Default Gateway : fe80::213:c4ff:fedd:14b0
  ND DAD          : Enabled
  DAD Attempts    : 3

  Vlan Name       : DEFAULT_VLAN
  IPv6 Status     : Disabled

  Vlan Name       : VLAN10
  IPv6 Status     : Enabled
  
  Address    |                                    Address
  Origin     | IPv6 Address/Prefix Length         Status
  –––––––––– + –––––––––––––––––––––––––––––––––– –––––––––
  dhcp       | 2001:db8:a03:e102::1:101/64        preferred
  manual     | fe80::1:101/64                     preferred

Switch(config)# show ipv6

Internet (IPv6) Service

  IPv6 Routing    : Disabled
  Default Gateway : 10.0.9.80
  ND DAD          : Enabled
  DAD Attempts    : 3

  Vlan Name       : DEFAULT_VLAN
  IPv6 Status     : Disabled

  Vlan Name       : VLAN10
  IPv6 Status     : Enabled
  
  Address    |                                        Address
  Origin     | IPv6 Address/Prefix Length             Status
  –––––––––– + –––––––––––––––––––––––––––---–––––-–– –––––––––
  autoconfig | 2930:0:a03:e102::127/64                preferred
  dhcp       | 2930:0:a03:e102:212:79ff:fe88:a100/64  preferred
  manual     | fe80::127/64                           preferred

Syntax:

show ipv6 nd

Displays the current IPv6 ND settings on the configured VLAN interfaces.

For example, the display below shows the output for a switch having IPv6 enabled on VLANs 1 and 22. 
Switch# show ipv6 nd

IPV6 Neighbor Discovery Configuration
  
  VLAN ID   DAD       RCH Time   NS Interval
            Attempts  (msecs)    (msecs)
  ––––––––– ––––––––– –––––––––– –––––––––––
  1         3         30000      1000
  22        3         30000      1000

Syntax:

show ipv6 vlan <vid>

Displays IPv6 addresses and IPv6 global configuration settings, the IPv6 status for the specified VLAN, the IPv6 addresses (with prefix lengths) configured on the specified VLAN, and the expiration data (Expiry) for each address.

  • ipv6 routing

    (See Router access and default router selection.)

  • default gateway

    Lists the IPv4 default gateway, if any, configured on the switch.It is a globally configured router gateway address and is not configured per-VLAN

  • nd dad

    Shows whether ND is enabled. The default setting is Enabled. Using ipv6 nd dad- attempts 0 disables ND.

  • DAD Attempts

    Indicates the number of neighbor solicitations the switch transmits per-address for duplicate (IPv6) address detection. Implemented when a new address is configured or when an interface with configured addresses (such as after a reboot).Default: 3; Range: 0–255 ms. A setting of “0” disables duplicate address detection. See Duplicate Address Detection (DAD).

  • VLAN Name

    Lists the name of a VLAN statically configured on the switch.

  • IPv6 Status

    For the indicated VLAN, shows whether IPv6 is disabled (the default) or enabled. See Configuring IPv6 addressing.

  • IPv6 Address/Prefix Length

    Lists each IPv6 address and prefix length configured on the indicated VLAN.

  • Expiry
    Lists the lifetime status of each IPv6 address listed for a VLAN:
    • Permanent

      The address will not time out and need renewal or replacement.

    • date/time

      The date and time that the address expires. Expiration date and time are specified in the RA used to create the prefix for automatically configured, global unicast addresses. The Address Status field in the show ipv6 command output indicates whether this date/time is for the “preferred” or “valid” lifetime assigned to the corresponding address. 

    Switch(config)# show ipv6 vlan 10

Internet (IPv6) Service

  IPv6 Routing    : Disabled
  Default Gateway : fe80::213:c4ff:fedd:14b0%vlan10
  ND DAD          : Enabled
  DAD Attempts    : 3

  Vlan Name       : VLAN10
  IPv6 Status     : Enabled

  IPv6 Address/Prefixlength         Expiry
  ––––––––––––––––––––––––––––––––– ––––––––––––––––––––––––
  2001:db8:a03:e102::1:101/64       Fri May 19 11:51:15 2014
  fe80::1:101/64                    permanent

Syntax:

show run

Along with the other elements of the current configuration, this command lists the statically configured, global unicast IPv6 addressing and the current IPv6 configuration per-VLAN. The listing may include one or more of the following, depending on what other IPv6 options are configured on the VLAN. Any SLAAC commands in the configuration are also listed in the output, but the actual addresses resulting from these commands are not included in the output.
  • ipv6 enable
  • ipv6 address fe80::<interface-id> link-local
  • ipv6 address <prefix>:<interface-id>/<prefix-length>
  • ipv6 address autoconfig
  • ipv6 address dhcp full [rapid–commit]
  • ipv6 <global–unicast–address>/<prefix> 
Switch(config)# show run

Running configuration:
. . .
vlan 10
   name "VLAN10"
   untagged 1–12
   ipv6 address fe80::1:101 link-local
   ipv6 address dhcp full rapid–commit
. . .

Statically configured IPv6 addresses appear in the show run output.

Commands for automatic IPv6 address configuration appear in the show run output, but the addresses resulting from these commands do not appear in the output.