[ixpmanager] sflow daemon

[Nick Hilliard]

On 07/11/2013 07:16, Rowan Thorpe wrote:
>> Is sflowtool supposed to be daemonized, or is there a script that
>> kicks it off?  It feels like I am missing a piece.
> 
> Daemon. It seems there might be two areas for improvement in the
> documentation(?):

sflowtool is started as a pipe by the sflow-to-rrd-handler script, and
sflow-to-rrd-handler is daemonised.

> 1) I can't find a link from the standard "installation instructions"
> page to the sflow installation page, I only find it by navigating via
> "pages" on the github wiki...

I agree that the documentation needs to be updated.  It would be best to
include a diagram explaining how we set it up.

In fact, INEX runs multiple sflowtool instances.  We send all our sflow
data to a centralised collector, and it uses sflowtool with different
command line arguments to fan the sflow data out from there to several
other systems.  These other systems use "sflowtool -l" to pipe the data to
various daemons.  One of these systems handles the p2p stuff.

> NB: A small gotcha which bit me hard was that because I was integrating
> IXP-Manager onto a server which was also cloning other functionality
> from a previous server, there was already a script running sflowtool on
> a separate port for unrelated data-collection. Unfortunately it was
> running from root crontab rather than system cron (or better yet - init)
> and every few days it would do a "killall sflowtool, archive log-file,
> re-run sflowtool" cycle, with no logging of the fact. It took me
> a while (longer than I'd like to admit) to diagnose why the IXP-M
> sflowtool was dying every few days...

oops, awkward. :-)

> FWIW: a month or two ago I posted an ITP (intent to package) and I
> packaged and uploaded a Debian package (therefore Ubuntu, etc) for
> sflowtool to the mentors server at Debian and asked for a Debian
> Developer to sponsor getting it into the official repos (I also
> included an init-script I wrote for it - which should be
> platform-agnostic enough BTW), but no-one responded yet :-( In the
> process I even shook out some small sflowtool bugs and helped the
> upstream sflowtool developer to patch them, hence the recent version
> bump of that too :-) If anyone knows a Debian Developer who might want
> to sign and push my packaging efforts so that sflowtool can become
> easier to install on lots of systems, please urge them to visit and give
> input/feedback: http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=724939

Yep, I saw that, but have no contact with the debian people.  I also
submitted a couple of sflowtool patches, which made it into sflowtool 3.30
(would recommend using this version for IXP manager, as it behaves much
better with sflow-to-rrd-handler).

Nick