Skip to content
/ cibh Public

Cows in Black Helicopters -- an SNMP based traffic grapher

License

Notifications You must be signed in to change notification settings

rfdrake/cibh

Repository files navigation

Build Status Coverage

CIBH

This is used to take SNMP usage information from routers and convert it to maps. The maps are drawn using xfig.

I fear you won't get very far if you've never used this before. I need to include example .fig files to show how the interfaces are tied to lines and how those lines are colored with usage data.

Names

CIBH was originally called the barn because it reminded Pete of the old barns in wyoming that were held together by rotting wood and bailing wire. I'm not sure how it got the name cows in black helicopters, except that there was a transition at some point from a bird into a beast (cow) and the meancow got put up as the index page.

You might also see this code referred to as snowbeast. That was the name given to the sun server at Sprint that hosted it. Before that it was run from a smaller sun box called snowbird.

What's New?

Graphviz support for maps. d3 charting.

I had to rewrite the support for 64-bit counters because we didn't have it anymore. I also modernized some of the perl because of the changes to the language in the last 12 years or so.

I don't touch the core code very much except to move it around or clean it up. I'm mainly extending in new directions. Adding support for new datasource backends is my current objective.

I've recently migrated to dzil for software management. If you don't want to use it then you may use the generated Makefile.PL instead.

Why run it?

There are several reasons you might still be interested in this:

  • It's very reliable
  • Despite how hard it is to use, there still aren't many comparable programs out there
  • Flexibility. Since the code is small it's possible to add features without spending tons of time on it

Authors

All principal code is from Pete Whiting and was originally written probably somewhere around 1998?

The updates for modern perl and reimplementing 64bit counters were done by me, Robert Drake.

I've updated the documentation somewhat. I still don't anticipate anyone who hasn't run it before from being able to figure it out, but I'm trying to cater right now to people familiar with it, but who may have forgotten some of the features it has.

Build the other tools

I suggest you run this on a modern linux box. Whichever you choose, use a package manager to install the dependencies.

To run cibh you need to install many packages and all of their dependencies. The minimal set includes:

  • gd: library for building png images
  • GD.pm: Perl module for accessing gd
  • net-snmp: SNMP library
  • Graphviz: (optional) to support graphviz input/output

Some of these may require you to install other packages (gd, for example, requires libpng, zlib and libjpeg.)

Easy mode:

# libsnmp-dev and build-essential should only be needed for building the app
sudo apt-get install libgd-gd2-perl libsnmp-dev parallel snmp-mibs-downloader build-essential
sudo cpanm --installdeps .
dzil build

Install the perl modules

Once you get the above packages built and installed you should be ready to run with cibh. CIBH is broken into two main parts - the perl modules and the scripts. To install the modules run the following commands:

perl Makefile.PL
make
sudo make install

The last step requires you to have write access to your to the perl library subdirs so you may need to run "sudo" or be root.

If you don't have root access, you can use the local::lib package to install into a local directory structure, or you can use "carton" to run everything based off of the cpanfile.

Optional Dependencies

If you run rancid, you might put a copy of "par" in the path. Alternatively, if you've installed GNU parallel, it will be used.

O. Tange (2011): GNU Parallel - The Command-Line Power Tool, ;login: The USENIX Magazine, February 2011:42-47.

Get the target directories ready

For sizing your disk you might consider how many mibs you think you will be polling and how frequent you want to poll. I grab about 2000 mibs every 5 minutes. Each sample takes up 12 bytes of data, so do a little math and make a partition to store the data.

The tool is currently set up to make separate directories for each router. This helps keep the number of entries in a single directory of manageable size. Further, it tries to maintain the concept of separate networks as well, so if you manage more than one network, they can be kept separate.

Most of the scripts will use a configuration file. A sample of this file, dot.cibhrc.sample, is included. Copy it to /etc/cibhrc.

If you need to change the location of the file there are several options. By default you can use /usr/local/etc/cibhrc, or /opt/cibh/etc/cibhrc, or you can override it completely by setting the CIBHRC environment variable.

If none of these options work for you, you can change the CIBH::Config module to point to the new location directly.

Once you've decided where it should go, you need to edit the cibhrc file.

Notice where it thinks it should store the snmp polled data. Using my structure this will be in /data/ittc/snmp. The other directory, map_path, is where it will store xfig files which have been recolored according to network utilization. More on that later. If you have multiple networks then set the network variable to be equal to the NETWORK shell variable. This will allow you to set the NETWORK shell variable in a script (running out of cron, for example) and get consistent behavior in all of the tools. All of the options in the .cibhrc file can be overridden on the command line, so take a look at them and tweak as needed. Some of the command line options do not appear in the cibhrc file - I haven't yet gone through and documented everything, so take a look at the first few lines of the code. The names should pretty much explain what they are for.

You may also need to modify the cibh/scripts/collect script and set the proper path for usage2fig to find the xfigs in. If you don't have any xfigs just comment out the line that says usage2fig.

Build your snmp mibs

This is the real configuration step. The file build-snmp-config is the one I use to do this. You could do it by hand, if you are sufficiently patient and have a small network, but I don't see that happening. The mib info table has four columns, the hostname, the mib, the command to run once the mib has been collected and a filename. The command can be anything that eval can handle in perl. I have provided three that I find useful:

  1. Store - stores the mib value in the file with .text appended to the filename.
  2. GaugeAppend - append the data with a timestamp and the value to the filename. The data is stored as integers in network order, 4 byte timestamp and 4 byte value.
  3. CounterAppend - append the data in a similar way, but assume this data is coming from a counter, so get the last sample (stored in the file) and figure out the difference and store that - this makes a counter look like a gauge.

You can combine these. I usually store interface gauges as GaugeAppend,Store. If you do CounterAppend,Store, the value stored by Store will be the "gauge-like" value, not the counter. This allows it to work with the mapping tools.

build-snmp-config tries to figure out what kind of box it is going against, and if it is a cisco it uses some special cisco mibs for things like the cpu utilization. You may want to add your own oids for other router types.

When build-snmp-configs runs, it looks for descriptions on the interfaces so it knows how to connect two sites. In some cases it can also use IPs, but it needs a coherent description to make sense of things. The format for the description looks like this:

description To bb1-jbert, Gig1/5 <extra info here like circuit ID>

If need be, the format can be completely changed in .cibhrc by modifying the destination and accept lines.

Poll your network

You should now be ready to poll. Try it with the poll command:

snmp-poll

Without the -quiet option you should see some status fly by. The first time through it will create the directories needed (pay attention to your data_path setting in .cibhrc.) You should be able to go look in the directories. Any file that ends in .text should be human readable. The files that are the result of counters will take three runs to get something valid stored in them.

Set up a job to poll from cron. I have included a sample script that does this: scripts/collect. I run it from cron with:

*/5 * * * * cibh/scripts/collect ittc

If I were monitoring multiple networks I would use:

*/5 * * * * cibh/scripts/collect net1 net2 net3 ...

You will probably also want to automate the rebuilding of snmp configs nightly, in case of changes to the routers.

# run build-snmp-configs at 3am
0 3 * * * cibh/scripts/build-snmp-configs data/<network>/routers 2>/dev/null

Charting and Mapping in xfig

If you look at the provided example core.fig and sanfran.fig you'll see a simple network setup.

xfig is not a very user friendly application so you'll probably use it mostly for positioning things and grouping them, but hand edit the files for common changes.

Some conventions:

Any ## is replaced with usage information looked up based on another line in the compound object.

If it's looking up cpu usage for a host the line might say #routername/cpu1.m or for lines connecting two routers it might say #bb1-rtr-name--bb2-rtr-name

These lines are regex so in some advanced cases you might have a line that says bb(\d+)-houston--bb(\d+)-dallas if you wanted to match any and all routers between houston and dallas.

Sometimes you want to break out links between routers into separate lines. To do this you can change the description to create a unique name for each link.

int fa0/2
 description To gw1-router_0_5, Primary Link
int fa0/3
 description To gw1-router_0_6, Backup Link

Then in your .fig file you would make two links like this:

#bb1-big-rtr--gw1-router_0_5
#bb1-big-rtr--gw1-router_0_6

Special note about the 3d script

This script takes the normal boxes and adds a bezeled border around the edges. If you want to make it work you'll need to make sure the script_path is correct in cibhrc then toggle it for a page by putting &td=1 for the parameters.

If you decide you like it you could turn it on globally.

Extra bugs

If you pass a non-number to pack() like NaN it hangs on some systems. I guarded this by checking for an error in snmp-poll, but we might want to additionally say if (!isnumber()) inside GaugeAppend/CounterAppend.

About

Cows in Black Helicopters -- an SNMP based traffic grapher

Resources

License

Stars

Watchers

Forks

Packages

No packages published

Languages