This article provides the steps for configuring the NTP service on an ESX/ESXi 4.0 host to allow remote queries. This allows external clients to use
ntpdc to retrieve server status information, including information on upstream NTP servers that are used for time synchronization. This information may be useful while troubleshooting NTP time synchronization.
These steps are not necessary for other versions of ESX/ESXi, such as 4.1, as those versions permit remote queries by default.
The NTP client tools
ntpdc may be installed by default on Linux distributions as part of the NTP package. If these command line utilities are not available, see your Linux distribution's documentation.
To configure the ESX/ESXi 4.0 host's NTP daemon to permit remote status queries:
/etc/ntp.confin a text editor. For more information, see Editing configuration files in VMware ESX (1017022).
restrict default kod nomodify notrap noquery nopeerAllow remote queries of the ESX/ESXi NTP daemon's status, by removing the
noqueryoption from that entry. The edited version of the entry looks like this:
restrict default kod nomodify notrap nopeer
ntpqto connected to and remotely query your ESX/ESXi host's NTP server. For more information, see Troubleshooting NTP on ESX and ESXi (1005092).