Chap2er 7-9 Flashcards
yeah
DHCP messages that are broadcasts
discover, request
DCHP messages that are unicasts
offer, acknowledgment
Order of DHCPV4 messages
DISCOVER, OFFER, REQUEST, PACK (ACKNOWLEDGE)
T/F: A client configured to use DHCP sends out a discover message on boot
TRUE
T/F: A DCHPREQUEST message is unicast
FALSE
What are the MAC and IPs in DHCPDISCOVER
FF-FF-FF-FF-FF-FF and 255.255.255.255
What IP does a PC use when requesting an IP
255.255.255.255
What DHCP message is sent by a server to let the client know it can use an IP
DHCPACK
T/F: All messages in DHCP lease renewal are unicast
TRUE
What protocol assigns IPs, and what port does it use
DHCP, 67
What is a result when DHCP is not working
hosts are assigned IP in the 169.254.0.0/16 network
What is the effect of ip dhcp exclude-address
IPs from to will not be assigned
What is the subnet mask equivalent of /23
255.255.254.0
Command to show all MAC addresses for IPs in DHCP
show ip dhcp binding
Ports used for DHCP traffic
67, 68
Why do ISPs assign DHCP addresses to routers
easy address management
What is typically used to configure connection to ISP
set WAN connection to DHCP
Advantage of configuring Cisco router as relay agent
provides relay services for multiple UDP connections
If a company uses SLAAC to config IPV6 addresses, what is used as the default gateway for hosts
link-local address of router interface attached to the network
How do hosts verify IPV6 is unique
sends neighbor solicitation message and makes sure there’s no router advertisement
DHCP IPV6 steps
solicit, advertise, request, reply (SARRy)
Command to enable O flag
ipv6 nd other-config-flag
What happens when PC tries to configure DHCP (M flag is 0, O flag is 1)
uses info contained in RA message and contacts DHCP server for more info
What needs to be enabled on a router to receive prefix and prefix length on hosts
ipv6 unicast-routing
Exhibit where 0 DHCP clients. Why?
state is not maintained by DHCP server
What conclusion can be drawn from DHCP configuration exhibit
router is configured for stateless DHCPv6
What IPV6 addressing is configured by the o flag
stateless DHCPv6
Exhibit: what should be done to give PC-A an automatically assigned IP
add DHCP relay
Exhibit: why are clients not getting DNS server
router is configured for SLAAC
T/F: The M flag is stateful DHCP
TRUE
T/F: ip address autoconfig is stateless DHCP
TRUE
T/F: HSRP is an open standard protocol
FALSE
Cisco proprietary protocol that provides redundancy through the use of an active device and standby device
HSRP
Open standard protocol that provides redundancy through virtual master router and backups
VRRP
Cisco proprietary protocol for load sharing
GLBP
Nonproprietary IPv4 election-only protocol with limited scalability
VRRPv2
Cisco proprietary protocol for IPV6 load balancing
GLBP for IPV6
Cisco proprietary protocol for IPV4 load balancing
GLBP
Nonproprietary protocol for ICMP for IPV4 redundancy
IRDP
Cisco proprietary protocol that only permits one router in a group to forward IPV6 packets
HSRP for IPV6
Nonproprietary FHRP implementation that’s IPV4, election only, and has one master router per group
VRRPv2
How often do HSRP routers send hello packets to each other by default
3 seconds
What happens over HSRP failover process
Forwarding router fails, standby router stops receiving hello messages, standby router assumes role of forwarding router, new forwarding router assumes MAC and IP of virtual router
Which MAC is used by a host connected to two L3 switches (and a virtual router)
the MAC of the virtual router
Using active and standby routers is a feature of _____
HSRP
Which default gateway should be set on a host connected to a FHRP network
the IP of the virtual router
