Module 8 Flashcards
What does SLAAC stand for?
Stateless Address Autoconfiguration
SLAAC is a method used by IPv6 devices to automatically configure their own IP addresses.
What is a Global Unicast Address (GUA)?
An IPv6 address that is globally routable and reachable on the Internet
GUAs are unique across the entire Internet.
What is a Link Local Address (LLA)?
An IPv6 address that is valid only within the local network segment
LLAs are used for communication within a single network segment and are not routable.
What is the purpose of the Router Solicitation (RS) message?
To request Router Advertisement (RA) messages from routers
This is part of the process for devices to discover routers and obtain network configuration information.
What does the Address Autoconfiguration Flag indicate?
It indicates whether a device should use SLAAC to create an IPv6 GUA
This flag is part of the RA message sent by routers.
What command enables IPv6 routing on a router?
ipv6 unicast-routing
This command must be executed in global configuration mode.
What command is used to define a DHCPv6 pool name?
ipv6 dhcp pool POOL-NAME
Replace POOL-NAME with the desired name for the DHCPv6 pool.
What is Duplicate Address Detection (DAD)?
A process used to ensure that an IPv6 address is unique on the network
DAD is implemented using ICMPv6 to prevent address conflicts.
What does the M flag indicate in Router Advertisements?
Whether to use a stateful DHCPv6 server to obtain an IPv6 GUA
If the M flag is set to 1, the client is instructed to contact a DHCPv6 server.
Fill in the blank: The command to configure a DHCPv6 server on an interface is _______.
ipv6 dhcp server POOL-NAME
This command binds the interface to the specified DHCPv6 pool.
What does the O flag indicate in Router Advertisements?
Whether to use a stateless DHCPv6 server for additional configuration parameters
If the O flag is set to 1, clients can request additional configuration from a DHCPv6 server.
What command is used to verify the DHCPv6 pool and its parameters?
show ipv6 dhcp pool
This command displays details about the configured DHCPv6 pool.
True or False: A Cisco IOS router can function as a DHCPv6 server, client, or relay agent.
True
Cisco IOS routers are versatile and can take on multiple roles in DHCPv6 configurations.
What is the purpose of the DHCPv6 Relay Agent?
To forward DHCPv6 messages between clients and servers on different networks
This is necessary when clients and servers are not on the same subnet.
What command is used to enable Stateless DHCPv6 on an interface?
ipv6 nd other-config-flag
This command sets the O flag to 1, allowing clients to obtain additional configuration from a DHCPv6 server.
What is the default behavior when SLAAC is enabled?
Hosts automatically create their own IPv6 GUA based on RA messages
SLAAC allows devices to generate their own addresses without needing a DHCPv6 server.
What command is used to verify if a router is enabled to send RA messages?
show ipv6 interface
This command checks the status of IPv6 on the router’s interfaces.
What is the primary function of the Neighbor Solicitation (NS) message?
To determine the link-layer address of a neighbor or to perform DAD
NS messages are essential for address resolution in IPv6.
What is the function of the DHCPv6 SOLICIT message?
To initiate communication with a DHCPv6 server and request configuration information
This message is sent by clients seeking IPv6 address and configuration details.
What command is used to configure the DHCPv6 relay destination?
ipv6 dhcp relay destination ipv6-address [interface-type interface-number]
This command specifies the address of the DHCPv6 server and the interface to use.
What is the role of the DHCPv6 Client?
To acquire an IPv6 configuration from a DHCPv6 server
A DHCPv6 client requests addressing and configuration parameters.
What is the significance of the prefix length in an IPv6 address?
It indicates the number of bits used for the network portion of the address
The prefix length is essential for routing and subnetting.
What does the command ‘ipv6 enable’ do on an interface?
Enables IPv6 processing on that interface
This command is necessary to allow the interface to participate in IPv6 networking.
What is the function of the DHCPv6 ADVERTISE message?
To respond to a client’s SOLICIT message and provide available options
This message is part of the DHCPv6 communication process.
What does the command ‘show ipv6 dhcp binding’ display?
It shows the binding of IPv6 addresses assigned to clients by the DHCPv6 server
This information is crucial for tracking address allocations.
Fill in the blank: The command to verify that the DHCPv6 relay agent is operational is _______.
show ipv6 dhcp interface
This command checks the status of the DHCP relay agent’s interface.
What is the purpose of Neighbor Advertisement (NA) messages?
To respond to Neighbor Solicitation messages and provide information about the sender
NA messages are part of the Neighbor Discovery Protocol in IPv6.
What are the main objectives of the module on SLAAC and DHCPv6?
Configure dynamic address allocation in IPv6 networks
The objectives include explaining how an IPv6 host can acquire its IPv6 configuration through SLAAC and DHCPv6.
What does SLAAC stand for?
Stateless Address Autoconfiguration
SLAAC enables hosts to create their own unique IPv6 global unicast address without needing a DHCPv6 server.
What is the function of a DHCPv6 relay agent?
To forward DHCPv6 messages between clients and a DHCPv6 server on a different network
The relay agent configuration is similar to that of an IPv4 router as a DHCPv4 relay.
What command is used to verify the operational status of a DHCPv6 relay agent?
show ipv6 dhcp interface
This command allows you to check the status of the DHCPv6 relay agent.
What are the three flags included in an ICMPv6 Router Advertisement (RA) message?
A flag, O flag, M flag
These flags inform the host of the dynamic options available for IPv6 address configuration.
What does the A flag in an RA message signify?
Use Stateless Address Autoconfiguration (SLAAC) to create an IPv6 GUA
This flag indicates that the host can create its own IPv6 address.
What is the purpose of the O flag in an RA message?
Indicates that additional information is available from a stateless DHCPv6 server
This allows the host to seek further configuration parameters.
What does the M flag in an RA message signify?
Use a stateful DHCPv6 server to obtain an IPv6 GUA
This flag tells the host to rely on a DHCPv6 server for address assignment.
True or False: Stateful DHCPv6 requires SLAAC.
False
Stateful DHCPv6 does not depend on SLAAC; it can operate independently.
What message does a host send to request an RA when using SLAAC?
Router Solicitation (RS) message
This message is sent to the IPv6 all-routers multicast address of ff02::2.
What does a host do after receiving a Router Advertisement (RA) message?
It creates a unique IPv6 GUA using the provided network prefix
The host uses the information in the RA to configure its IPv6 address.
Fill in the blank: The DHCPv6 server does not maintain a list of _______.
IPv6 address bindings
This characteristic defines the stateless nature of DHCPv6.
What is the purpose of Duplicate Address Detection (DAD) in SLAAC?
To ensure that the IPv6 GUA is unique
DAD uses an ICMPv6 Neighbor Solicitation (NS) message to check for address conflicts.
What is the default multicast address for all IPv6 routers?
ff02::2
This address is used by hosts to send RS messages to request RAs.
What command is used to manually configure an IPv6 global unicast address on a router?
ipv6 address ipv6-address/prefix-length interface configuration command
This command is essential for setting up IPv6 addresses on router interfaces.
How often does a router send ICMPv6 RA messages by default?
Every 200 seconds
Routers send RA messages periodically to assist hosts in autoconfiguring their IPv6 addresses.
What is the role of a Stateless DHCPv6 server?
To provide configuration parameters without maintaining address bindings
It is used in conjunction with SLAAC to give additional information.
What is the significance of the link-local address in IPv6?
It is automatically created by the host when it boots and the interface is active
The link-local address is used for local communication within the same network segment.
What is the IPv6 address format for a link-local address?
fe80::/10
Link-local addresses begin with the prefix fe80::.
How can a Windows host dynamically acquire an IPv6 GUA?
Through SLAAC or DHCPv6
Most Windows hosts are configured to dynamically obtain IPv6 addresses.
What does the command ‘ipconfig /all’ do?
Displays all IPv6 addressing information for Windows hosts
This command helps verify what IPv6 configurations have been assigned.
What does the term ‘Global Unicast Address (GUA)’ refer to?
An IPv6 address that is globally routable and unique
GUAs are essential for communication across the internet.
What is the purpose of the ‘show ipv6 interface’ command?
To verify that a router has joined the IPv6 all-routers group
This command checks the router’s participation in the multicast group.
What is the primary function of the DHCPv6 server?
To assign IPv6 addresses and provide configuration parameters to clients
DHCPv6 can operate in both stateful and stateless modes.
What happens if a host receives a Neighbor Advertisement (NA) message during DAD?
The address is not unique, and the host must generate a new interface ID
This process ensures that each address used on the network is unique.
