All devices on cacti are graphing except one which is not

[ramaning]

I have cacti server and after a power cut, the server shut down for about 24hrs. I turned it back on and after that all devices are graphing except for one router which is not graphing.
My cacti log shows

11/27/2012 04:16:21 PM - SYSTEM STATS: Time:19.3581 Method:spine Processes:1 Threads:1 Hosts:51 HostsPerProcess:51 DataSources:1414 RRDsProcessed:682
11/27/2012 04:16:20 PM - CMDPHP: Poller[0] ERROR: Detected RRDtool Crash attempting to perform write
11/27/2012 04:16:18 PM - CMDPHP: Poller[0] ERROR: Detected RRDtool Crash attempting to perform write
11/27/2012 04:16:17 PM - CMDPHP: Poller[0] ERROR: Detected RRDtool Crash attempting to perform write
11/27/2012 04:16:14 PM - CMDPHP: Poller[0] ERROR: Detected RRDtool Crash attempting to perform write
11/27/2012 04:16:12 PM - CMDPHP: Poller[0] ERROR: Detected RRDtool Crash attempting to perform write
11/27/2012 04:16:10 PM - CMDPHP: Poller[0] ERROR: Detected RRDtool Crash attempting to perform write
11/27/2012 04:16:09 PM - CMDPHP: Poller[0] ERROR: Detected RRDtool Crash attempting to perform write
11/27/2012 04:16:07 PM - CMDPHP: Poller[0] ERROR: Detected RRDtool Crash attempting to perform write .

Please I need help on this.

Thank you in advance.

[gandalf]

The error seems to be related to "rrdtool update" which is performed after each polling interval to write data to rrd files.
Please try to rename the rrd file in question. Cacti will then recreate a new file and try to update it. In case this works, the "old" rrd file is broken.

Or try to "rrdtool dump" and restore the rrd file to work around a possible rrd file issue
R.

[ramaning]

Hi,
Thanks for the reply on my post. I have done all you told me to do but still able to graph.
I renamed the rrd file to .old tried rebuilding the poller cache but it didnt work.

Rrdtool dump and restore also didnt work.

What should I do next please.

Thank you.

Richard.

[gandalf]

I need more precise info; not only "didn't work". Did you receive an error message? Does dump/restore work but _not_ resolve the issue?
R.