[collectd] Server does not receive client data (network between both looks OK).

[Bruno Costacurta]

Hello,

I'm trying to setup a server / client collectd config.
The server is running and produces data as expected as shown via  
Apache website.
The client is also running and sending data but apparently server  
receives nothing. However a test using a telnet between client and  
server looks OK.

Here-after the config and tcpdump output.
Maybe my server config is missing something to act as a listener ?
Maybe a Interface setup ?
Thanks for your attention and clue.

##### server config:
Mode server
Hostname "YYYYY.lws-hosting.com"
BaseDir "/var/lib/collectd"
PIDFile "/var/collectd.pid"
PluginDir "/usr/lib/collectd"
TypesDB "/usr/share/collectd/types.db"

LoadPlugin logfile
<Plugin "logfile">
   LogLevel "debug"
   File "/var/log/collectd.log"
   Timestamp true
   PrintSeverity true
</Plugin>

LoadPlugin network
<Plugin "network">
   Listen "YYYYY.lws-hosting.com" "22061"
   Server "YYYYY.lws-hosting.com" "22061"
</Plugin>

LoadPlugin rrdtool
<Plugin "rrdtool">
   DataDir "/var/lib/collectd/rrd"
   CacheTimeout 900
   CacheFlush 120
   WritesPerSecond 50
</Plugin>

LoadPlugin cpu
LoadPlugin load

<LoadPlugin "perl">
   Globals true
</LoadPlugin>

<Plugin "perl">
   BaseName "Collectd::Plugins"
   LoadPlugin "OpenVZ"
</Plugin>


##### client config:
Mode client
Hostname "aspire4750"
BaseDir "/var/lib/collectd"
PluginDir "/usr/lib/collectd"
TypesDB "/usr/share/collectd/types.db"

LoadPlugin logfile
<Plugin logfile>
   LogLevel "debug"
   File "/var/log/collectd.log"
   Timestamp true
   PrintSeverity true
</Plugin>

LoadPlugin rrdtool
LoadPlugin cpu
LoadPlugin df
LoadPlugin disk
LoadPlugin entropy
LoadPlugin hddtemp
LoadPlugin load
LoadPlugin memory
LoadPlugin network

<Plugin "network">
   Server "vps622YYYYY.lws-hosting.com" "22061"
</Plugin>

LoadPlugin processes
LoadPlugin swap
..etc..
..etc..


##### IP packets send by the client to the server:
tcpdump -i wlan0 port 22061 and host YYYYY.lws-hosting.com
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on wlan0, link-type EN10MB (Ethernet), capture size 65535 bytes
18:17:19.480429 IP aspire4750.local.54746 > XXXXX.22061: UDP, length 881
18:17:29.476113 IP aspire4750.local.54746 > XXXXX.22061: UDP, length 912
18:17:39.476338 IP aspire4750.local.54746 > XXXXX.22061: UDP, length 871
18:17:39.476787 IP aspire4750.local.54746 > XXXXX.22061: UDP, length 883
18:17:49.472704 IP aspire4750.local.54746 > XXXXX.22061: UDP, length 913
18:17:49.473126 IP aspire4750.local.54746 > XXXXX.22061: UDP, length 908
..etc..
..etc..

##### telnet to test connection between client and server:

## client side:
  telnet XXXXX 22061
Trying 93.184.47.217...
telnet: Unable to connect to remote host: Connection refused (note :  
correct as no telnetd on server port 22061)

## server side:
/usr/sbin/tcpdump  port 22061 and host XXXXX
listening on venet0, link-type LINUX_SLL (Linux cooked), capture size  
65535 bytes
18:24:23.964418 IP YYYYY.lws-hosting.com.22061 >  
ip-78-141-130-18.dyn.luxdsl.pt.lu.44760: Flags [R.], seq 0, ack  
1528218477, win 0, length 0

-> so connection between client to server looks correct as server  
received the telnet try from client, correct ?

However the collectd log neither the Apache website shows data from  
client. The data from the server are shown correctly.

I suppose my server config is missing something to act as a listener ?
Thanks for your attention and clue.
Bye,
Bruno