[rrd-developers] rrdcached and --skip-past-updates

[Martin Sperl]

Hi!

With regards to template support for rrdcached (on the client side)
which just reacently got merged, I just started to wonder how
"--skip-past-updates" is related to rrdcached.

I wonder if it is really a necessity to have this test in rrd_update.c:
    if (extra_flags != 0) {
        rrd_set_error("The caching daemon cannot be used together with "
                      "templates and skip-past-updates yet.");
        goto out;
    }

It should be fairly easy to "ignore" the error from rrdcached
communication passing extra_opts to rrdc_update and there doing the
sanity check on the response from rrdcached.

Something like that in rrd_client.c in rrdc_update:
/* ignore time update errors in case RRD_SKIP_PAST_UPDATES is set  */
if (status && (extra_flags & RRD_SKIP_PAST_UPDATES))
    if ((strstr(res.message,"illegal attempt to update using time")
        && strstr(res.message," when last update time is "))
            status=0;

Is this a valid observations?

Martin