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Having trouble with ntp on 3 of 4 host servers in a cluster
When executing /usr/sbin/ntpq -p on on host, I get a delay in response (obviously it is trying) then:
localhost: timed out, nothing received
On two other hosts, when executing /usr/sbin/ntpq -p, it immediately returns
/usr/sbin/ntpq: read: Connection refused
the fourth host returns data from all registered time servers in /etc/ntp.conf
The servers are running OEL Linux.
Any guidance appreciated. I don't have elevated privileges on the host servers, so anything I get back will have to be passed onto the Linux administrator.
forgive my ignorance. Command nc is new to me; while I read up on it, when I executed it, I substituted both IP address and hostname for <server_IP>. Then it just stalled. apparently listening on port 123? Ctrl-C terminated the state of nc.
Long story short; I cannot tell if servers are listening on the 3 hosts where ntp apparently not working. The fourth host where ntp is working and ntpq returns results gives me the same result from the nc command.
If remote host is listening, this is what you will see, in this example, I am using "0.centos.pool.ntp.org" as NTP server:
Code:
$ nc -vu 0.centos.pool.ntp.org 123
Ncat: Version 7.50 ( https://nmap.org/ncat )
Ncat: Connected to 192.241.146.233:123.
nc (netcat) is what I use to determine if remote host is listening to a perticular UDP port. In this case of NTP, it should listen on port 123/UDP.
OK. Then apparently it is not listening as I am not getting anything back. At this point I have submitted a trouble ticket request to our linux administrators to review the problem and ( hopefully ) repair the issue.
OK. Then apparently it is not listening as I am not getting anything back. At this point I have submitted a trouble ticket request to our linux administrators to review the problem and ( hopefully ) repair the issue.
dc.901 - problem was with /etc/ntp.conf, parameter "restrict default ignore" commented off, then service ntp restart cleared the problem. Thank you for your effort!
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