NTP

[Qcheck]

My NTP daemon has been failing on my RHEL 5 server. We use 0.rhel.pool.ntp.org, 1.rhel.pool.ntp.org and 2.rhel.pool.ntp.org.

I can't ping the above or nslookup.

Are these public ntp servers working or something else is wrong on my server?

Thank you.

[Steven E. Protter]

Shalom,

http://www.ntp.org

There are better public servers available.

Best servers are maintained by the US Navy and Hewlett Packard.

Those servers default are not that good.

SEP

[Matti_Kurkela · Accepted solution]

If you can't even nslookup the *.rhel.pool.ntp.org hosts, then your DNS configuration may have problems. Maybe you don't have access to a DNS server, or the DNS server cannot/will not resolve names of hosts outside your organization.

All *.pool.ntp.org hostnames are mapped to multiple IP addresses for load balancing purposes. Specifically, each of the *.rhel.pool.ntp.org seems to map to (at least) three different IP addresses, each in a different network segment. If you have all three hostnames configured, you're trying to reach at least 9 NTP servers.

0.rhel.pool.ntp.org:
62.236.120.71, 81.22.244.161 and 193.65.86.11.

1.rhel.pool.ntp.org:
80.75.100.83, 83.145.237.222 and 93.174.192.21.

2.rhel.pool.ntp.org:
87.108.20.70, 193.65.58.57 and 194.100.206.70.

MK

[Qcheck]

MK, You are right. I flushed the DNS and is working fine now.

Thank you...

[Qcheck]

Flushed the DNS and resolved the issue.

Thank you.