Cacti监控有数据，但是全为0怎么回事

shoringchow

求解：
在监控机上测试远端主机# snmpwalk -v 2c -c public 192.168.2.55 .1.3.6.1.4.1.2021.13
UCD-DLMOD-MIB::dlmodNextIndex.0 = INTEGER: 1
UCD-DISKIO-MIB::diskIOIndex.1 = INTEGER: 1
UCD-DISKIO-MIB::diskIOIndex.2 = INTEGER: 2
UCD-DISKIO-MIB::diskIOIndex.3 = INTEGER: 3
...........................
LM-SENSORS-MIB::lmTempSensorsValue.5 = Gauge32: 66500
LM-SENSORS-MIB::lmTempSensorsValue.6 = Gauge32: 60500
LM-SENSORS-MIB::lmTempSensorsValue.7 = Gauge32: 63000
LM-SENSORS-MIB::lmTempSensorsValue.8 = Gauge32: 64500
在监控机上测试rrd数据： rrdtool fetch /home/www/cacti/rra/cnweb005_io_read_6466.rrd AVERAGE
1347847800: 0.0000000000e+00 0.0000000000e+00
1347848100: 0.0000000000e+00 0.0000000000e+00
1347848400: 0.0000000000e+00 0.0000000000e+00
1347848700: 0.0000000000e+00 0.0000000000e+00
1347849000: 0.0000000000e+00 0.0000000000e+00
web下的图像：