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What is restrict in NTP?
By default, all the clients (any IPv4 or IPv6 addresses of any network) except localhost are restricted to access the NTP server. You can use the system ntp restrict default-v4 command to allow access for all IPv4 addresses to your NTP server and to configure NTP access restriction options for IPv4 addresses.
Where is the NTP configuration file?
/etc/ directory
conf file is a text file with configuration information for the NTP daemon, ntpd . On Unix-like systems it is commonly located in the /etc/ directory, on Windows system in the directory C:\Program files (x86)\NTP\etc\ or C:\Program files\NTP\etc\ .
How to configure NTP access restrictions global configuration?
♦ query-only—Allows only NTP control queries. ♦ serve-only—Allows only time requests. ♦ serve—Allows time requests and NTP control queries, but does not allow the switch to synchronize to the remote device. ♦ peer—Allows time requests and NTP control queries and allows the switch to synchronize to the remote device.
Where do I find the NTP configuration file?
The default location for the file is /etc/ntp.conf and you can view the file by entering the following command: ~]$ less /etc/ntp.conf. The configuration commands are explained briefly later in this chapter, see Section 22.16, “Configure NTP”, and more verbosely in the ntp.conf (5) man page.
How is time synchronization performed in a NTP setup?
In a large NTP setup (NTP servers at stratum 1 in the internet, with servers that source time at different strata) with servers/clients at multiple strata, NTP synchronization topology should be organized in order to produce the highest accuracy, but must never be allowed to form a time sync loop.
How to remove access control to NTP services?
To remove access control to the switch NTP services, use the no ntp access-group {query-only | serve-only | serve | peer} global configuration command. This example shows how to configure the switch to allow itself to synchronize to a peer from access list 99.