IPv6Privileged EXEC

show ipv6 dhcp binding

Shows all active DHCPv6 leases including client identifiers and expiry times.

Syntax·Privileged EXEC

show ipv6 dhcp binding [ipv6-address]

When to Use This Command

Verifying that clients are successfully obtaining addresses from DHCPv6.
Troubleshooting DHCPv6 assignment failures.
Auditing which clients are using which IPv6 addresses.
Finding stale bindings that need to be cleared after address conflicts.

Command Examples

Show all active DHCPv6 bindings

R1# show ipv6 dhcp binding

Client: FE80::A8BB:CCFF:FEA1:1234 
  DUID: 00030001AABBCCA11234
  Username : unassigned
  IA NA: IA ID 0x00070001, T1 43200, T2 69120
    Address: 2001:DB8:1::A
            preferred lifetime 86400, valid lifetime 86400
            expires at Jun 10 2026 03:14:07 (86282 seconds)

One active binding. The client's link-local address (FE80::...) identifies the client. DUID is the unique device identifier. The assigned address is 2001:DB8:1::A with 86400s valid lifetime. T1/T2 are renew/rebind times.

No bindings — DHCPv6 server has no active leases

R1# show ipv6 dhcp binding

Empty output means either no clients have received addresses, or bindings have expired. Check 'show ipv6 dhcp pool' to confirm the pool is configured and has addresses available.

Understanding the Output

Key fields: Client link-local = identifies who the client is on that segment. DUID = permanent unique ID from the client's NIC (like a MAC address for DHCPv6). IA NA = Identity Association for Non-temporary Address — the address block. T1 = renew timer (usually 50% of valid lifetime); T2 = rebind timer (usually 80%). Address lifetime = how long the address is valid.

CCNA Exam Tips

CCNA exam tip: DHCPv6 uses DUIDs instead of MAC addresses for client identification — a fundamental difference from DHCPv4.

CCNA exam tip: 'show ipv6 dhcp binding' is the IPv6 equivalent of 'show ip dhcp binding'.

CCNA exam tip: Empty output doesn't mean DHCPv6 is broken — verify that clients are configured to use DHCPv6 (M or O flag).

CCNA exam tip: Use 'clear ipv6 dhcp binding *' to remove stale entries (like 'no ip dhcp conflict address' equivalent).

Common Mistakes

Mistake 1: Expecting a MAC address in the binding output — DHCPv6 uses DUIDs (64-bit or longer identifiers), not MAC addresses.

Mistake 2: Confusing 'show ipv6 dhcp binding' (leases) with 'show ipv6 dhcp pool' (pool config and statistics).

Mistake 3: Thinking empty binding output means DHCPv6 is broken — clients using SLAAC won't appear here.

Related Commands

ipv6 dhcp pool [name]

Creates a DHCPv6 server pool and enters DHCPv6 pool configuration mode. Used to configure stateful DHCPv6, where the server assigns IPv6 addresses and provides DNS/domain information to clients.

ipv6 dhcp server [pool-name]

Enables a DHCPv6 server on an interface and links it to a named DHCPv6 pool. Clients on that interface receive IPv6 addresses and parameters from the specified pool.

ipv6 nd managed-config-flag

Sets the Managed (M) flag in IPv6 Router Advertisement (RA) messages sent from this interface. When M=1, clients are instructed to obtain their IPv6 address from a DHCPv6 server (stateful DHCPv6) rather than using SLAAC.

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