Should you wish to modify an existing DB, you can freely change the TITLE, VLABLE, Colors, or add and remove Service statements.You may not add a MATCH. You may remove a MATCH, but the RRD file will remain the same size.

To change the name of a MATCH, follow the procedure below.

Changing the name of a MATCH

To change the name of a MATCH, you may do so, but you will have to manually change the name in the RRD file as well -

Once you have finished making changes, the new file needs to be put in place on both server and client machines. You will want to stop and start the server (fwplatd). Either by killing the daemon and starting it manually, or by running

Imposing a maximum value to data readings

Should you get spurious high values input into an RRD, it can make viewing the good data difficult due to scaling problems. For example, should the average number of connections be 17000/minute, but you get a spurious reading of 5,000,000/minute, then it will make all the long term graphs impossible to read.

To fix this, you can impose size limits on the RRD, dump it into XML, and then restore it, whilst telling it to watch out for out of range values (the -r switch):

stats # rrdtool tune fwconnections.rrd -a tcp:60000 -a udp:60000 -a icmp:60000
stats # rrdtool dump fwconnections.rrd > /tmp/fwconnections.xml
stats # cp -p fwconnections.rrd  /tmp/fwconnections.rrd.bak    
stats # rrdtool restore -r /tmp/fwconnections.xml fwconnections.rrd           
out of range found [ds: 0], [value : 5.9652320453e+07]
out of range found [ds: 1], [value : 5.9652258991e+07]
out of range found [ds: 2], [value : 5.9652323309e+07]
out of range found [ds: 0], [value : 1.8837575632e+07]
out of range found [ds: 1], [value : 1.8837568060e+07]
out of range found [ds: 2], [value : 1.8837575897e+07]
out of range found [ds: 0], [value : 1.2647158082e+06]
out of range found [ds: 1], [value : 1.2647280896e+06]
out of range found [ds: 2], [value : 1.2647137002e+06]
stats # 
stats # rrdtool tune fwconnections.rrd -a tcp:U -a  udp:U -a icmp:U
stats # rrdtool info fwconnections.rrd
Note: After fixing the spurious values, I switch back to having no limit ('U'). you may prefer to keep the limits in place.
Steve Campbell <>, 16 Jul 2002