Re: recommendations for external montioring services?

[Mark Gauvin <MGauvin () dryden ca>]

Solar winds as you send in the specific mib required to monitor and a  
week later it's general release


Sent from my iPhone

On 2011-12-13, at 7:11 PM, "Robert Brockway"  
<robert () timetraveller org> wrote:

> On Mon, 12 Dec 2011, Eric J Esslinger wrote:
>
> > I'm not looking to monitor a massive infrastructure: 3 web sites, 2  
> > mail
> > servers (pop,imap,submission port, https webmail), 4 dns servers
> > (including lookups to ensure they're not listening but not  
> > talking), and
> > one inbound mx. A few network points to ping to ensure connectivity
> > throughout my system. Scheduled notification windows (for example,
> > during work hours I don't want my phone pinged unless it's everything
> > going offline. Off hours I do. Secondary notifications if problem
> > persists to other users, or in the event of many triggers. That  
> > sort of
> > thing). Sensitivity settings (If web server 1 shows down for 5 min,
> > that's not a big deal. Another one if it doesn't respond to repeated
> > queries within 1 minute is a big deal) A Weekly summary of issues  
> > would
> > be nice. (especially the 'well it was down for a short bit but we  
> > didn't
> > notify as per settings') I don't have a lot of money to throw at  
> > this. I
>
> Hi Eric.  The feature set you are describing should be in any  
> monitoring
> system worthy of the name.  I've used Nagios to good effect for the  
> best
> part of the last 12 years or so.  Before that I used Big Brother,  
> which
> sucked in various ways.
>
> I did an evaluation on a wide variety of FOSS monitoring systems 2-3  
> years
> ago and Nagios won at the time (again).  Generally I found the
> alternatives had problems that I considered to be quite serious  
> (such as
> being overly complicated or doing checks so frequently that they  
> loaded
> the systems they were supposed to be monitoring[1]).
>
> I'm currently trialing Icinga, a fork of Nagios.
>
> Puppet can be set up to manage Nagios/Icinga config which cuts down  
> on the
> admin overhead.
>
> Nagios/Icinga can be hooked up to Collectd to provide performance  
> data as
> well as alert monitoring.
>
> One concern about external monitoring services is the level of  
> visibility
> they need to have in to your network to adequately monitor them.
>
> My recommendation is to do a proper risk assessment on the available
> options.
>
> > DO have detailed internal monitoring of our systems but sometimes  
> > that
> > is not entirely useful, due to the fact that there are a few 'single
> > points of failure' within our network/notification system, not to
> > mention if the monitor itself goes offline it's not exactly going  
> > to be
> > able to tell me about it. (and that happened once, right before the  
> > mail
> > server decided to stop receiving mail).
>
> There are a couple of ways to deal with this.  Some monitoring
> applications can fail-over to a standby server if the primary  
> fails.  But
> this isn't even really necessary.  You will arguably gain higher
> reliability by running multiple _independent_ monitors and have them
> monitor each other[2].  I have often used this approach.
>
> The principal aim here is to guarantee that you are alerted to any  
> single
> failure (a production service, system or a monitor).  Multiple
> simultaneous failures could still produce a blackspot.  It is  
> possible to
> design a system that will discover multiple simultaneous failures,  
> but it
> takes more effort and resources.
>
>
> [1] Sometimes I wonder if the people developing certain systems have  
> any
> operational experience at all.
>
> [2] A system designed to fail-over on certain conditions may fail to
> fail-over, ah, so to speak.
>
> Cheers,
>
> Rob
>
> -- 
> Email: robert () timetraveller org        Linux counter ID #16440
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