[rrd-users] Rrd update second try

[Simon Hobson]

Kenneth Miller wrote:

>I have been capturing interface data for a about a year into an rrd 
>and would like to add and capture multicast data now, while 
>preserving the existing data.  We already created a new rrd with all 
>the new variables and keep the old rrd as an existing reference.  I 
>should have used rrdupdate to add this variable to the exisitng rrd? 
> Since there is a new one created, could I merge 2 rrds into 1?

Can you clarify what you currently have ? I think you have an old RRD 
file that you've stopped updating, and a new RRD file with both the 
old and additional datasets. If that is the case, you can combine 
them with an IF statement to date data from the old file if 
time<switchover point, and the new file if time>switchover point.

Eg :
   DEF:data1a=rrd1.rrd:data1:AVERAGE
   DEF:data1b=rrd2.rrd:data1:AVERAGE
   CDEF:data1=TIME,${ChangeDate},LT,data1a,data1b,IF