[rrd-developers] rrdcached protocol issue: clients don't reconnect

[Thorsten von Eicken]

I'm having problems with clients not reconnecting if I restart the 
rrdcached daemon. For example, collectd prints out the following type of 
error forever if I do a "service rrdcached restart" (using unix socket, 
but I believe same happens with TCP):

Oct 30 05:03:52 sketchy1-1b collectd[3551]: rrdcached plugin: 
rrdc_update (/rrds/.../memcached_command-set.rrd, 
[1256878677:2904863359], 1) failed with status -3.

I believe this comes from rrd_client.c in response_read:
  buffer_ptr = fgets (buffer, sizeof (buffer), sh);
  if (buffer_ptr == NULL)
    return (-3);
  chomp (buffer);

Seems to me that this is to be expected:
       "gets() and fgets() return s on success, and NULL on error or 
when end of file  occurs
       while no characters have been read."

The proper error handling to close the connection seems to be missing?

Thorsten