windtear 追求完美

http://windtear.net/archives/2006/06/13/001004.html

mrtg 的加和等计算绘图 v.s. RRD 的加和等计算绘图

20060530 别人问的
搜索了一下发现有人遇到
解决办法是写 Target 的时候就计算

如：
Target[multiple]: a.a&c.c:comm{at}host + b.b&d.d:comm{at}host
这样就计算 a.a+b.b 和 c.c+d.d

没测试

我都是用RRD自己做加和 (DEF 和 CDEF)
示意代码如下：

foreach $eachdevice (@validdevice) {
$topush= 'DEF:HttpOutKb'.$count.'='.$RRDS_DIR.'/'.$eachdevice.'.rrd:HttpOutKb:AVERAGE';
push (@DEF, $topush);

$sumexp .= 'HttpOutKb'.$count.',';
}

for (2..$sitetotalnum) { $sumexp .= '+,'; }
$sumexp = substr($sumexp,0,length($sumexp)-1);

$sumexp = "CDEF:HttpOutKbSum=".$sumexp.",1000,/"; or
$sumexp = "CDEF:HttpOutKbSum=".$sumexp.",8,*,1000,/";

push (@DEF, $sumexp);

@PLOT = (
    'AREA:HttpOutKbSum#00CC00:Sum Traffic To Clients ',
    'GPRINT:HttpOutKbSum:LAST:%7.2lf MB/s last',
    'GPRINT:HttpOutKbSum:AVERAGE:%7.2lf MB/s avg',
    'GPRINT:HttpOutKbSum:MAX:%7.2lf MB/s max\j',
);

前面加和等计算写好了  最后直接调用 graph 绘图就行了