[collectd] Unable to run collectd under OpenVZ

[Robert Brockway]

Hi all.  I've started using collected recently and I love it.  I've tried 
a lot of perf monitoring tools and finally I've found a perf monitoring 
tool that makes sens (IMHO) :)

I've run in to an interesting problem though.

At work we have several Linux boxes running OpenVZ.  I'd like to monitor 
the hardware nodes (HNs) and the virtual environments (VEs) using 
collectd.  I know I can use the openvz plugin to do this but...

I'd like to store all the data (CSV and/or RRD) on a VE and have all HNs 
send the reports.

I can have all the HNs report fine when they send to a HN but when I send 
to a VE it failed.  I have tried this at two different physical locations 
and got exactly the same problems.  The hardware at the two different 
sites is completely different but all HNs are running Debian 5.0.4 (Lenny) 
with kernel 2.6.26-2-openvz-amd64.

I used tshark to examine the connection today and saw something quite 
unusual.  I'be RTFMed on this but with no luck.  In the output below 
192.168.10.192 is the VE and 192.168.10.19 is the HN.  The VE is running 
on a seperate HN.

In general apps don't know or care they are running on a VE so I was 
surprised to have problems.  OTOH I suppose we rarely if ever use UDP 
services with VEs.  I may be posting to the OpenVZ lists too.  If this 
problem was common to UDP on VEs I'd expect to have found reports about it 
but I didn't.

This appears to have for every packet sent:

# tshark udp port 25826

0.000000 192.168.10.19 -> 192.168.10.192 IP Bogus IP header length (0,
must be at least 20)
2.038417 192.168.10.19 -> 192.168.10.192 IP Bogus IP header length (0,
must be at least 20)
2.040255 192.168.10.19 -> 192.168.10.192 IP Bogus IP header length (0,
must be at least 20)
2.040416 192.168.10.19 -> 192.168.10.192 IP Bogus IP header length (0,
must be at least 20)
2.090841 192.168.10.19 -> 192.168.10.192 IP Bogus IP header length (0,
must be at least 20)
62.036655 192.168.10.19 -> 192.168.10.192 IP Bogus IP header length (0,
must be at least 20)
62.036794 192.168.10.19 -> 192.168.10.192 IP Bogus IP header length (0,
must be at least 20)
62.038321 192.168.10.19 -> 192.168.10.192 IP Bogus IP header length (0,
must be at least 20)
62.038844 192.168.10.19 -> 192.168.10.192 IP Bogus IP header length (0,
must be at least 20)
122.035030 192.168.10.19 -> 192.168.10.192 IP Bogus IP header length (0,
must be at least 20)
122.035150 192.168.10.19 -> 192.168.10.192 IP Bogus IP header length (0,
must be at least 20)

Cheers,

Rob

-- 
Email: robert at timetraveller.org
IRC: Solver
Web: http://www.practicalsysadmin.com
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