Alternatives to Nagios

I've never been a fan of putting all my eggs in one basket. Although, by all accounts, Nagios looks like it will be an adequate solution to network monitoring, there are alternatives. Here are the ones I've come across for my "just in case this doesn't work" list:

OpenNMS
One that I've seen quite a few times in my research is called OpenNMS. The website states that

OpenNMS is the world's first enterprise grade network management platform developed under the open source model. It consists of a community supported open-source project as well as a commercial services, training and support organization.

World's first, eh? And what's your criteria for establishing whether something "enterprise grade" or not? Ah, well. Cynicism is unbecoming, and the product looks decent enough, whether or not it's the "world's first."

I do have a few concerns about this product, though, that encouraged me to move it to the "just in case" list. I came across this on a mailing list:

The big thing that makes OpenNMS a non-starter for me was the inability to create dependencies between services. It's a pain to do in Nagios but it's there and that is a critical tool for enterprise level operations.

Yeah, that would be a bit of a show stopper, unless you're doing nothing more sophisticated than running a plain vanilla server install with a few simple services -- and who does that anymore?

Zenoss
This one seems relatively new, but has been getting a fair bit of buzz. Zenoss, according to the website, is as follows:

Zenoss Core is an enterprise-grade network and systems monitoring product that delivers the functionality IT operations teams need to effectively manage the health and performance of their entire infrastructure through a single, integrated package... Zenoss has changed the game by offering a complete, easy-to-use solution as a free..., downloadable, open source software product.

Okay, so far, so good. I perused the website fairly extensively, and have to admit that it looks like a very slick package -- arguably more feature complete and functional than Nagios. There is a fully functional demo available, so I can check things out without having to do a local install, and see if it's more hype than reality... and this appears not to be the case. This is encouraging. Plus, the app appears to be written in Python, so it'll be portable and easy to modify and extend, should the need arise.

I may in fact do a double install -- both Nagios and Zenoss, just to see which one is more appropriate for my needs.

Zenoss seems very impressive.

Server Monitoring: Nagios

As I mentioned last time, I am looking for an easy, free, stable, and highly functional network monitoring system. Nagios is my first venture into this investigation. Nagios has been around for awhile, and I believe that I evaluated it a few years ago before throwing my hands up in frustration and doing a quick and dirty solution myself. In all fairness, I was incredibly busy at the time, and probably didn't give it a fair shake.

According to the website, it will do exactly what I want:

Nagios is a host and service monitor designed to inform you of network problems before your clients, end-users or managers do. It has been designed to run under the Linux operating system, but works fine under most *NIX variants as well. The monitoring daemon runs intermittent checks on hosts and services you specify using external "plugins" which return status information to Nagios. When problems are encountered, the daemon can send notifications out to administrative contacts in a variety of different ways (email, instant message, SMS, etc.). Current status information, historical logs, and reports can all be accessed via a web browser.

Well, I've never been much of one for believing in the whole truth in advertising thing, so I decided to give it a go on my own, and see how it works.

The network I decided to test it on consists of six machines. In addition, I have two development servers in an external data center that were doing nothing but humming, so I elected to include them in the tests. The machines are a mixture of FreeBSD and a couple of different Linux distros (CentOS and Debian).

Prior to actually installing this package, I did a bit of reading on their website. They have a number of helpful screenshots; here are a few that were of interest to me.

This is the status detail screen (and it would appear that someone is having a bad day with this particular network!). It looks quite helpful, and provides a good "dashboard" view of the various processes on a given machine.

Now this is interesting -- a status map of a network segment. I'm not sure how you define the map (but suspect it is painful), but it is an interesting method of graphically representing the layout of various workstations and servers. Nice touch.

This gives the bird's eye view of all monitored services. Simple, and effective. It seems that you can group services together, which would be very helpful.

After I finished amusing myself with screenshots and the propoganda on their site, I went over to the Wikipedia entry to see what it had to say. It's a short article, and simply lists the services it monitors, has pointers to helpful install guides, and mentions that it came out in 2002, when it used to be called NetSaint. The talk page had this obscure comment:

I would say this is a very handy application when argumented with Cacti. I just set up one and its really cool to see it in action.

I presume "argumented" was supposed to be "augmented", but there you go. But was is this "Cacti"? I'll have to find out.

I'm going to try a test install of this on the weekend. I'll keep you posted.