undefined symbol

[Oussama-drici]

when using json-output libjson-output.so plugin for ipfixcol2 is unable to find the symbol ipx_msg_ipfix_get_drec.

ipfixcol2 -c udp2json.xml
ERROR: Configurator: Collector failed to start: Failed to load a plugin from '/usr/local/lib/ipfixcol2/libjson-output.so': /usr/local/lib/ipfixcol2/libjson-output.so: undefined symbol: ipx_msg_ipfix_get_drec

[johncena336]

Hello, I'm seeing the same issue. How was this resolved? Thank you

[sedmicha]

Hello, I'm seeing the same issue. How was this resolved? Thank you

Hello, are you running the latest master or one of the tagged release versions? Also make sure that libfds is built and installed properly (see https://github.com/CESNET/ipfixcol2#how-to-build).

If you still can't get it to work please provide the exact error message, your configuration, the exact version you're running, and which system and version you're running into the issue on.

Cheers, Michal

[johncena336]

Hi Michal, thank you for your reply. I am running the latest master release on a fresh Ubuntu 26.04 LTS install and I think I need a little help. I need to implement a simple collector with udp2json functionality. I have used your default configuration example. I have followed all the steps listed in the documentation, including for libfds, but the error is still present.

ERROR: Configurator: Collector failed to start: Failed to load a plugin from '/usr/local/lib/ipfixcol2/libjson-output.so': /usr/local/lib/ipfixcol2/libjson-output.so: undefined symbol: ipx_msg_ipfix_get_drec

The output plugin is listed as present:

• Name : json
  Description: Conversion of IPFIX data into JSON format
  Path: /usr/local/lib/ipfixcol2/libjson-output.so
  Version: 2.2.0

2$ ls -l /usr/local/lib/ipfixcol2/ | grep json
-rw-r--r-- 1 root root 78520 May 8 12:43 libjson-kafka-output.so
-rw-r--r-- 1 root root 173688 May 8 12:43 libjson-output.so

Thank you!

[sedmicha]

Huh, I just tried compiling and running it myself on Ubuntu 26.04 and I am indeed getting the same problem. Seems like this is a new problem specifically on that system... I will look into it and let you know.

[sedmicha]

I have just merged a fix. Please try again with the latest master.

[johncena336]

Hi Michal. Thank you for your help. I tried again with the latest version. The error is gone and the application is started. However, I cannot access the JSON output through HTTP. I have tried both with a UDP netflow stream from a device and using ipfixsend2 with the provided sample file. In both cases, I get a ERR_INVALID_HTTP_RESPONSE in the browser (I tried different browsers).

[sedmicha]

That's because the server output is not a HTTP server, it is simply a TCP server. You can open a socket or use e.g. netcat and you get the JSON streamed line per line.

nc 127.0.0.1 8000

[johncena336]

Hi Michal. Thank you! It's OK now.