DHCP Operation
Clients lease the IPv configuration information a client receives from the server for an administratively defined period, typically anywhere from 24 hours to a week or more.
What is a lease?
The Cisco router server that assigns and manages IPv4 addresses from specified address pools configured on the router to automatically distributed to clients.
DHCP
A method in which a device can obtain an IPv6 global unicast address without the services of a DHCPv6 server.
What is Stateless Address Autoconfiguration (SLAAC)?
•If DHCPv4 is working correctly when the client is on the same subnet or VLAN what could be configured incorrectly on the router to cause the problem?
•What is the DHCP relay agent?
Network administrators assign ______ addresses to network devices whose locations (physical and logical) are not likely to change.
What is static IPv4?
A client starts with the first step in the four-step process to obtain a lease. The packet contains the client's own MAC address to discover available DHCPv4 servers.
What is a DHCP Discover (DHCPDISCOVER)?
The Cisco IOS command used to exclude specific addresses IPv4 addresses that should not be assigned to other devices.
What is ip dhcp excluded-address?
The messages that are sent by routers to provide addressing information to clients configured to obtain their IPv6 addresses automatically.
What is Router Advertisement (RA) message ?
•The command to confirm that the router interface acting as the default gateway for the client is operational. Not show run!
•What is the show interfaces (interface) command?
The client has no valid IPv4 information at bootup, it uses Layer 2 and Layer 3 broadcast addresses in this type of DHCP packet to communicate with the server.
What is a DHCPDISCOVER?
The DHCPDISCOVER is an IPv4 ________ message with a destination IPv4 address of 255.255.255.255.
What is broadcast?
This solution enables a router to forward DHCPv4 broadcasts to the DHCPv4 server.
What is a helper address?
•Messages originating from the DHCPv4 server are sent as unicasts directly to the client.
•What are DHCPOFFER and DHCPACK?
•The server uses the __________ command to detect clients. The client uses ____________ to detect conflicts. If an address conflict is detected, the address is removed from the pool and not assigned until an administrator resolves the conflict.
•What is ping and Address Resolution Protocol (ARP)?
•The router is receiving DHCP requests from the client. The source IP address is _____________ because the client does not yet have an IP address. The destination is __________ because the DHCP discovery message from the client is sent as a broadcast.
•What is 0.0.0.0 (source) and 255.255.255.255 (destination)?
DHCPv4 messages are encapsulated within the UDP transport protocol. Name the two port numbers.
What is 67 and 68?
Three steps to configuring DHCPv4 server on a router.
What is:
1. Excluding IPv4 Addresses
2.Configuring a DHCPv4 Pool
3. Configuring Specific Tasks
•Using SLAAC Operation there are two ways a PC can create its own unique 64-bit Interface ID (IID) to create a global unicast address.
•What are:
•EUI-64 - Using the EUI-64 process, PC1 will create an IID using its 48-bit MAC address.
•Randomly generated - The 64-bit IID can be a random number generated by the client operating system.
•This command disables all DHCP server and relay functionality on the router.
•What is no service DHCP?
•Dynamically assigns, or leases, an IPv4 address from a pool of addresses for a limited period of time, as configured on the server, or until the client no longer needs the address.
•DHCP
Name the DHCP lease origination steps in order.
What is
1. Discover
2. Offer
3. Request
4. ACK
By default, the ip helper-address command forwards the eight UDP services: Name four.
•There are two methods available for the dynamic configuration of IPv6 global unicast addresses.
What are:
•Stateless Address Autoconfiguration (SLAAC)
•Dynamic Host Configuration Protocol for IPv6 (Stateful DHCPv6)
•The five troubleshooting issues with DHCPv4 and DHCPv6 involve the same tasks. List 3 of them.
•Resolve Address Conflicts
•Verify Physical Connectivity
•Test Connectivity using a Static IP Address
•Verify Switch Port Configuration
•Test Operation on the Same Subnet or VLAN
The command that displays all address conflicts recorded by the DHCPv4 server. The server uses the ping command to detect clients. The client uses Address Resolution Protocol (ARP) to detect conflicts.
What is the show ip dhcp conflict?