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I had originally written this article for xmodulo . Cacti  is a popular network graphing tool widely used by many service providers. For those of you who have been using Cacti to visualize the performance of various elements of your network, it is sometimes necessary to migrate Cacti and all its graph datasets from one server to another. Why? The current server may be old, or is running out of space and CPU, or you may simply want to move to new hardware platform. Whichever the case, it is possible to move Cacti data sets from one server to another, while minimizing disruptions in graph plotting. In this tutorial we will see just how easily we can do that. Step 1: Setting up Cacti in the New Server We will need to stop Cacti at the old server during the migration process. To minimize any gaps in graphs, we will prepare the newer server first (while Cacti at the old server is still running). We will start the process by installing Cacti in the new server. A  previous t...

I had originally written this article for xmodulo . Cacti  is a fantastic open source network monitoring system that is widely used to graph network elements like bandwidth, storage, processor and memory utilization. Using its web based interface, you can create and organize graphs easily. However, some advanced features like merging graphs, creating aggregate graphs using multiple sources, migration of Cacti to another server are not provided by default. You might need some experience with Cacti to pull these off. In this tutorial, we will see how we can merge two Cacti graphs into one. Consider this example. Client-A has been connected to port 5 of switch-A for the last six months. Port 5 becomes faulty, and so the client is migrated to Port 6. As Cacti uses different graphs for each interface/element, the bandwidth history of the client would be split into port 5 and port 6. So we end up with two graphs for one client - one with six months' worth of old data, and the other ...

Timezone Problem If no graph is being generated and the cacti log keeps telling about timezone problem then this can be done: ERROR SAMPLE PHP Warning:  strtotime(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'Asia/Dacca' for 'BDT/6.0/no DST' instead in /var/www/cacti/include/global_arrays.php on line 671  My timezone is Asia/Dhaka, so I modifed php.ini accordingly. [root@centu ~]# vim /etc/php.ini date.timezone = Asia/Dhaka [root@centu ~]# service httpd restart  Of course, PHP documentation should be consulted prior to editing php.ini. This may help: http://bd.php.net/manual/en/timezones.php Graphs Not Being Generated The poller needs to run at least once for the RRD (typically stored in /var/www...