System time on the ESXi host is not synchronized with the defined NTP servers

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

After adding multiple NTP servers within the VMware vSphere Web Client using the Time Configuration wizard, you experience these symptoms:

• The system time of the host is not successfully synchronized with the defined NTP servers.
• In the /etc/ntp.conf file on the hosts, you see an entry similar to:
  
  ...
  server nameserver1, nameserver2
  ...
  
  
• In the /var/log/syslog.log file on the host, you see the error:
  
  ntpd_intres[2461573]: host name not found: nameserver1, nameserver2

Cause

This issue occurs when multiple NTP servers are defined using a single comma with no space as a delimiter between the NTP server addresses. This generates an incorrect entry within the /etc/ntp.conf file on the host and therefore, the host interprets the defined value as one NTP server.

Resolution

This is a known issue affecting the VMware vSphere Web Client 5.1 and 5.5.

This issue is resolved in VMware vCenter Server 5.5 Update 2, available at VMware Downloads. For more information, see the Resolved Issues section in the vCenter Server 5.5 Update 2 Release Notes.

Currently, there is no resolution for ESXi 5.1.

To work around this issue, add a space after the comma when defining multiple NTP servers.

Example:

nameserver1, nameserver2