The NTP package contains ntp-wait, ntptrace, ntpd, ntpdate, ntpdc, ntpq, ntptime, tickadj and ntp-keygen. ntp-wait is useful at boot time, to delay the boot sequence until ntpd has set the time. ntptrace traces a chain of NTP servers back to the primary source. ntpd is a NTP daemon that runs in the background and keeps the date and time synchronized based on response from configured NTP servers. It also functions as a NTP server. ntpdate is a client program that sets the date and time based on the response from an NTP server. This command is deprecated. ntpdc is used to query the NTP daemon about its current state and to request changes in that state. ntpq is an utility program used to monitor ntpd operations and determine performance. ntptime reads and displays time-related kernel variables. tickadj reads, and optionally modifies, several timekeeping-related variables in older kernels that do not have support for precision timekeeping. ntp-keygen generates cryptographic data files used by the NTPv4 authentication and identification schemes.