perfSONAR User Q&A and Other Discussion

[Jon K Hellan <>]

Hi

I'm seeing behaviour in RRD-MA which looks a lot like memory corruption.

This is the perfsonar-bundle-2.0-RC1 bundle.

The error in the log is

ERROR - RRDStorageManager.rrdFetch: Cannot retrieve data from rrdjtool 
library: RRDFETCH failed: opening 's0_0.rrd': No such file or directory

In one sense, this is correct. There is indeed no such file.

The string s0_0.rrd only occurs in my config file as the end of a file 
name:

<nmwg:parameter 
name="file">/var/lib/nav/cricket-data/router-interfaces/trd-gw.uninett.no/pos0_0.rrd</nmwg:parameter>

I'm fetching utilization data for all interfaces in the config file. 
First in the 'in' direction, then in the 'out' direction. The query in 
the 'in' direction completes successfully.

I've traced the rrd calls with gdb, and the strange string is passed to 
rrdOpen after a number of reasonable rrd file names have been 
successfully processed.

Any tips on how to debug this?

Regards

Jon Kåre