First games with SNMP

Learning about the tools avaible in Linux:

The tools used for this tests where two Linux computer on each end of the WLL lan, the named software, ping, tcpdump and ###
Note: ### are internal marks for me to refind the paths I like to follow on later.

gxsnmp: Gnome MySQL based SNMP tool - probs at menu init. Hence look first at others..
scotty: TCL/TK script with big tool library, found earlier on doc about how to extend toward own MIBs -> don t know if breezecom MIBs are already in the MIB - they weren't. But putting them in was no problem
snmpd: Daemon, which can collect and also act as agent ->### could be useful for monitoring purposes of unattended Linux boxes. Also as shell based retrieving a statistic could be easy -> need closer look

scotty

The IP discover

pings each host, udp scans ports over 5000, icmp retrieve netmask, SNMP getrequest

Output of IP discover

Sun Mar 12 11:24:46 CET 2000 Discover 195.153.60 from 8306.s03.h08.distel.org [10.8.103.24] 3 nodes found on network 195.153.60 in 10 seconds. 6 routes traced in 49 seconds. 6 netmasks queried in 3 seconds. 4 snmp agents queried in 3 seconds. 6 ip addresses queried in 3 seconds. 1 networks discovered in 0 seconds. 6 gateways discovered in 0 seconds. 6 links discovered in 0 seconds. 3 nodes merged in 0 seconds. 7 tkined objects created in 0 seconds. Discover finished in 68 seconds

Generall

Middle mouse button to select and move around. The different tools give their output in their initially opened window, hence it is not good to lose this window.Right mouse button (RMB) will open the menu to retrieve further statistics.

SNMP Trouble - IP Trouble

Basic values can be queried like, the System parameters, traceroute and DNS lookup. This could come handy, in case of unknown network enviroments or manage of large networks. Also it is possible to put one whole map into a group icon and get in this way a overviewmap with less icons. While it is still possible to go into detail when necessary.

SNMP Monitor

You get small displays for viewing the interface traffic (load). The interfaces can be scaled, cleared and jumped. The output is maybe a bit small, but as I want to collect my own data and draw my own charts it is no problem.

Test

For a test I did a flood ping (as much pings as the CPU can do without waiting for reply). The Ethernet traffic Master-SA10 did grow not much, while the radio traffic went up to 29,6 percent (probably more taken on a longer term)

own work

As scotty/tkined doesn t have the Breezecom specific functions I learned TCL and added a module to access the MIB entities directly from a menu. In this way I could emulate the behaviour of the original Breezeview and add access to functions not accessible out of Breezeview.

SNMPc - Breezeview

The installation of the software was rather interesting. I needed to add the mib files by hand, also change the ini file to adjust the pathes. Finally the softwark worked, but only in the one mode. The functionality of log in as different Users was not possible. The graphs produced by the statistic function were good. However I preferred to use my own script, as I have better control over which data will be put into a graph, when the probes will be taken and the output format (ps or jpeg). Writing a control and data collection script in perl would also have the advantage, that I could react to certain values, prepare a row of tests done automatically, reproductible.

SNMP Perl script

Together with the UCD-SNMP package comes the an Perl module. The usage is easy. Also the gdchart module for creating graphs is no problem. Reaction on user signals, certain values and other events is possible using the huge module library. A cenario would, where change of mission critical SNMP parameters could be notified via SMS or email seems easy.