RTG (Bandwidth and 95th Percentile Monitoring) Installation and Configuration
What is RTG ?
RTG Stands for Real Traffic Grabber.RTG is a flexible, scalable, high-performance SNMP statistics monitoring system. It is designed for enterprises and service providers who need to collect time-series SNMP data from a large number of targets quickly. All collected data is inserted into a relational database that provides a common interface for applications to generate complex queries and reports. RTG includes utilities that generate configuration and target files, traffic reports, 95th percentile reports and graphical data plots. These utilities may be used to produce a web-based interface to the data.
Runs as a daemon, incurring no cron or kernel startup overhead
Written entirely in C for speed, incurring no interpreter overhead
Multi-threaded for asynchronous polling and database insertion
Inserts data into a relational database where complex queries and reports may be generated
Performs no data averaging in order to support billing, etc.
RTG comes as C source code and is intended to run on UNIX systems. RTG requires a UNIX system with POSIX thread support, 64-bit long integers and a sane compiler (gcc works great). RTG requires two external packages:
If you want to configure your database you must know the MYSQL root password. The createdb script will setup the database for RTG.
If you want to configure Rtg you need to edit two configuration files in /usr/local/rtg/etc folder i.e routers
routers file, adding each router you wish to SNMP poll, one per line. To specify a per-router non-default community string, add "router:community" in the routers file. To specify a per-router non-default response bit width, add "router:community:bits" in the routers file.
Edit rtgtargmkr.pl(located at /usr/local/rtg/etc) to change the default SNMP read community if necessary. To use 64bit OIDs (recommended if supported by the device), change the "bits" field in rtgtargmkr.pl to 64.
rtgtargmkr.pl script to manage the RTG target file. The first run will create a targets.cfg file.
This will create a targets.cfg file with all your routers and switches interfaces details in this.One more important thing is if you do any changes to your router configuration file you need to run the rtgtargmkr.pl otherwise it will not show the new changes after running this script you need to update your database to see these changes.When you run the perl script it will give the command name you need to run in mysql database command you can see one example as follows
Interface description changed.
Was: "global network 100Mbps"
Now: "global_network 100Mbps"
Suggest: UPDATE interface SET description='global_network 100Mbps' WHERE id=7
now you need to login in to your mysql database using the following command
#mysql rtg -p -u snmp
mysql> UPDATE interface SET description='global_network 100Mbps' WHERE id=7;
this will update the changes in your database.
Presently you need to do manually every time you do some changes and this one i don't like personally.
If the poller does not find a configuration file, it will create one in the current directory called "rtg.conf". You may need to edit this file if your installation is non-standard. If the poller is successful, the "Polls" counter in the statistics banner will increase and then a countdown to the next poll is displayed. The DBInserts should increment after the second polling round.
If rtgpoll or rtgplot cannot find an rtg.conf file in any of these paths, it will attempt to create one in the current working directory.Most users maintain a master rtg.conf file customized for their environment. rtg.conf contains the following configurable fields:
Interval is the time between successive polls of the target list,default is 300 seconds (5 minutes). HighSkewSlop defines the maximum number of Intervals allowed between two consecutive poll values before the time in seconds between said points is deemed too large to calculate a valid rate. With the default Interval and HighSkewSlop values, that time would be 300 * 3 (15 minutes). LowSkewSlop defines the minimum number of Intervals alloweed between two consecutive poll values before the time in seconds between said points is deemed two low to calculate a valid rate. With the default Interval and LowSkewSlop values, that time would be 300 * 0.5 (2.5 minutes). OutOfRange defines an upper bound above which rtgpoll will never attempt an insert into the database.
OutOfRange should be a multiple of the maximum number of bytes possible in the defined Interval for your highest speed link. The default OutOfRange value will suffice in most installations. SNMP_Ver specifies the SNMP version the poller will use. The number of threads rtgpoll will use is defined in the variable Threads.
Variables in rtg.conf must match the names above exactly.Comments and blank lines are allowed and the ordering of variables in rtg.conf does not matter.
The target file specifies the objects to be SNMP polled. Comments must be preceded with a '#' sign. Elements in the target file are tab delimited.
The format of the target file is fixed:
# Host OID 64/32 Community Table ID Description
Host = IP or hostname of target
OID = Full SNMP OID, e.g. .126.96.36.199.188.8.131.52.184.108.40.206
64/32/0 = Specify 64/32 bit objects or 0 for gauge objects
Community = SNMP Community
Table = MySQL table in the database to use
ID = A unique ID that is used with each insert
Description = Free text
rtgpoll first reads the configuration file, then the target file.For each SNMP poll, rtgpoll will attempt an SQL INSERT of the form:
INSERT INTO Table VALUES (ID, NOW(), bigint)
Where Table is the name of the database table and ID is an integer. Both Table and ID come from the target list, NOW() is the current timestamp and bigint is the delta value between successive SNMP polls.
RTG makes no attempt at determining rate; one must look at the time difference successive entries in the database. The RTG graphing and reporting tools automatically calculate rate.