Nagios Support Forum

Hi every one,

Hi,
I'm new to nagios. I have added a few servers in nagios monitoring . all pugins are working fine but when i add ntp service its shows like "NTP
UNKNOWN 01-02-2015 16:16:03 0d 16h 30m 27s 4/4 Invalid NTP response: 28 bytes read does not equal 12 plus 3584 data segment "
is it relavant to NTP service issue ?

Can you show the command and service definition you are using?

Have you tried running the plugin from the CLI?

What version of the plugins are you using?

Hi scottwilkerson ,

i am using check_ntp pluggin and am checked in CLI also results as : /usr/local/nagios/libexec/check_ntp -H localhost -w 0.5 -c 1 -j -1:100 -k -1:200
Invalid NTP response: 28 bytes read does not equal 12 plus 3584 data segment.

and plugins version is nagios-plugins-2.0.3

I might have to dig into the code I changed for this one, but can you try removing the -j and -k from your command first. Also what ntp server are you checking against? The particular error you are seeing is from a check against the ntp packet provided, that makes sure the size relayed by the device matches the actual packet size it sent, and that there is enough memory allocated to safely process the packet. In this case, your device seems to say the size is 12 + 3584 bytes, but it actually sent only 28. This might be an initialization packet of some sort, but it does seem a bit odd that it would claim to send so much data and instead send so little.

if i removing j & K it will working
check_ntp -H localhost -w 0.5 -c 1
no error provided.
i checked with different ntp servers like
server 2.in.pool.ntp.org
server 0.asia.pool.ntp.org
server 2.asia.pool.ntp.org
even checked above ntp servers same error occured.

using this command ./check_ntp -H localhost -w 0.5 -c 1 Result as

NTP OK: Offset -1.430511475e-06 secs|offset=-0.000001s;0.500000;1.000000;

let us know one thing what exactly usage of jitler (j)

pvkanna wrote:let us know one thing what exactly usage of jitler (j)

See: http://www.ntp.org/ntpfaq/NTP-s-sw-clocks-quality.htm