NTP Flashcards
Network Time Protocol
What is the purpose of NTP
Synchronizing internal clocks across all devices on a network
What is the command to view the time in Cisco IOS
sh clock
What is the default timezone for Cisco devices
UTC
What is the command to view the time source on Cisco devices
sh clock detail
What is the default time source for Cisco devices
Hardware calendar
T/F: Hardware calendar is considered an authoritative source
F
Internal hardware clock of a device will drift over time, so it is not the ideal source
What does an asterisk in front of the output of sh clock mean?
The time is not considered authoritative
What is the most important reason to have an accurate time on a device?
Accurate log keeping for troubleshooting purposes
What is the command to view a device’s logs
sh logging
What is the command to manually configure the time on a Cisco device
clock set
What config mode do you need to be in for clock commands
Priviledged EXEC mode
What is the command to manually configure the hardware clock (aka calendar)
calendar set
T/F: You never want the calendar and the clock on a device synchronized
F
It is always a good idea for the calendar and the clock to be synchronized
What is the command to view a device’s hardware clock
sh calendar
What is the command to sync a device’s calendar to its clock time
clock update-calendar
What is the command to sync a device’s clock to the calendar time
clock read-calendar
What is the command to configure the time zone on a Cisco device
clock timezone
T/F: Timezone must be configured from global config mode since it is part of the device’s running config
T
T/F: Timezone must be configured from priviledged EXEC mode since it is not part of the device’s running config
F
Timezone is part of the running config and therefore has to be changed in global config mode
What is the command to enable daylight savings time automatic adjustment
clock summer-time (timezone) recurring (day to switch) (day to switch back)
NTP prevents us from having to manually configure _____
time on devices connected to the network
T/F: NTP doesn’t prevent device clocks from drifting and becoming out of sync
F
Part of NTP’s purpose is to provide clock synchronization across multiple devices
T/F: It is possible for a device to become an NTP server and an NTP client at the same time
T