CentOS：

0.centos.pool.ntp.org

1.centos.pool.ntp.org

2.centos.pool.ntp.org

国内可用的

ntp.fudan.edu.cn 复旦

210.72.145.44 国家守势中心服务器

亚洲地区的ntp服务器

Bangladesh — bd.pool.ntp.org (0)

China — cn.pool.ntp.org (3)

Hong Kong — hk.pool.ntp.org (1)

India — in.pool.ntp.org (2)

Indonesia — id.pool.ntp.org (2)

Iran — ir.pool.ntp.org (0)

Israel — il.pool.ntp.org (3)

Japan — jp.pool.ntp.org (5)

Korea — kr.pool.ntp.org (4)

Malaysia — my.pool.ntp.org (3)

Philippines — ph.pool.ntp.org (0)

Singapore — sg.pool.ntp.org (3)

Taiwan — tw.pool.ntp.org (7)

Thailand — th.pool.ntp.org (1)

Turkey — tr.pool.ntp.org (1)

United Arab Emirates — ae.pool.ntp.org (0)

国外的：

time.nist.gov  美国

time-a.nist.gov

time-b.nist.gov

time-nw.nist.gov