[smokeping-users] High packet loss on graphs... for no reason

[George Tasioulis]

Hello,

I installed smokeping for the first time, couple of days ago on a CentOS 4.0 box.

Installation completed without any problems, and soon the first RRD files where generated and I could see them in my website ( http://ns1.cns.net.gr/smokeping/smokeping.cgi )

After a few minutes, I saw that I was getting strange packet loss results on the graphs (they are still there if you look in my website above. Eg on ISPs -> Forthnet this is my main ISP so 90,39% packet loss can't be true...)

I then tested my network by pinging from the same machine to the same hosts that are configured in the smokeping config with fping (from command line) and I wasn't getting any packet loss at all.

Here's a test fping pinging to 4 of my hosts:

[...]
85.196.16.134 : [19], 84 bytes, 2.27 ms (3.79 avg, 0% loss)
85.196.16.138 : [19], 84 bytes, 3.88 ms (3.91 avg, 0% loss)
85.196.17.110 : [19], 84 bytes, 2.49 ms (2.95 avg, 0% loss)
212.251.31.9  : [19], 84 bytes, 20.8 ms (21.6 avg, 0% loss)

85.196.16.134 : xmt/rcv/%loss = 20/20/0%, min/avg/max = 2.17/3.79/27.6
85.196.16.138 : xmt/rcv/%loss = 20/20/0%, min/avg/max = 3.83/3.91/4.01
85.196.17.110 : xmt/rcv/%loss = 20/20/0%, min/avg/max = 2.33/2.95/12.0
212.251.31.9  : xmt/rcv/%loss = 20/20/0%, min/avg/max = 18.5/21.6/30.1

       4 targets
       4 alive
       0 unreachable
       0 unknown addresses

       0 timeouts (waiting for response)
      80 ICMP Echos sent
      80 ICMP Echo Replies received
       0 other ICMP received

 2.17 ms (min round trip time)
 8.07 ms (avg round trip time)
 30.1 ms (max round trip time)
       19.734 sec (elapsed real time)

In sum I'm pinging 11 hosts, so I don't think that there's a timeout problem. Also all hosts are max 500km away, so ping times are very low.

My version of Fping is: 

[root at ns1 bin]# /usr/local/sbin/fping -v
/usr/local/sbin/fping: Version 2.4b2_to $Date: 2001/01/25 11:25:04 $
/usr/local/sbin/fping: comments to noc at zerohype.com

My next move was to lower the step/pings setting from 300/20 to 300/10 then 300/5 and finally 120/5 (of course every time I deleted the imgcache and datadir folder contents)

Well, things got better... but I still get a lot of packet loss without any reason really.

I use a Cisco 3725 on a 4Mbps leased line, with only 2% avg CPU load, and all interfaces have 0 errors, 0 CRCs etc.

I also tried pinging a host in which I get large amounts of packet loss in smokeping with regular ping from the same PC for about an hour and there was not even one packet that didn't returned.

I see people pinging 300... 400 hosts at a time with no problems at all and I can't figure out what I'm doing wrong here.

I also upgraded to v2 rc5, which has a new FPing.pm but the packet loss keeps coming.

Any ideas?  

Thank you very much in advance,

Tasioulis George
Network & Support Operations Manager
CNS - Computer & Network Solutions
Irakleous Filonos 3, GR-34100 Chalkida, Greece
E: g.tasioulis at cns.gr
W: http://www.cns.gr
 

--
Unsubscribe mailto:smokeping-users-request at list.ee.ethz.ch?subject=unsubscribe
Help        mailto:smokeping-users-request at list.ee.ethz.ch?subject=help
Archive     http://lists.ee.ethz.ch/smokeping-users
WebAdmin    http://lists.ee.ethz.ch/lsg2.cgi