Using sysctl(1) to gather resource consumption data

David Wolfskill david at
Sun Sep 14 12:45:15 UTC 2008

On Sun, Sep 14, 2008 at 09:11:36PM +1000, Norberto Meijome wrote:
> ...
> Out of curiosity, how does bsnmpd compare to your approach with regards to
> impact on the system. It is part of 7.0 , not sure about previous versions, and
> it is definitely a more standard and cross platform approach , with support @
> NOC / alerting side of things. 
> (for what is worth, i've only used net-snmpd , not bsnmpd )...

Understood.  As I understand it, an SNMP daemon (whether bsnmpd or
net-snmpd) would require some configuration on the remote host, and I
wasn't willing to require that.

Also, the only times I have used SNMP, it has been using a version that
did not support encryption in any form (as for as I know), and since
some of the transit was over facilities we don't control, I thought it
would be a bit more sensible to use SSH for the transport.

There is a moderate amount of work in setting up the SSH connection in
the first place: the first version of my script actually had the
"shepherd" script establish a new SSH connection to each remote host
every 5 minutes; examing a ktrace of that convinced me that SSH session
creation was not something I wanted to do on a frequent basis for a
mechanism that was intended to be low impact.

But keeping that SSH session around and "squirting" a little over 800
bytes of payload down the pipe every 5 minutes -- or even every 10
seconds -- shouldn't be too much impact.  (As a colleague pointed out,
that's probably less impact than running top(1) has.)

Granted, this isn't intended for the one "shepherd" script to deal with
thousands of remote hosts -- but I believe that "hundreds" is feasible.

Mind, I'm not especially keen on re-inventing stuff that already works
(or can be reasonably persuaded to work).  But in this case, running an
SNMP daemon seemed to fail to meet my (admittedly, somewhat self-
imposed) requirements.

David H. Wolfskill				david at
Depriving a girl or boy of an opportunity for education is evil.

See for my public key.
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