Reach Out and Watch Your Network
Longitude's agent-less architecture gives you a flexible solution for network monitoring.
Longitude Version 4.0
1: Virtually inoperable or nonexistent
5: Average, performs adequately
Many system management utilities do their thing by installing some sort of
agent on the target machine that communicates with a central console. Being
selfish with my system resources, I always ask myself, "How much RAM is
this agent going to take up? How many CPU cycles will be allocated to managing
There are certainly pros and cons to both the agent-based and agent-less approach,
but with all the interfaces out there like WMI, it amazes me that some products
today still mess around with agents -- but that's just me. Longitude from Heroix
immediately stood out from the rest of the pack, in my opinion, as there are
no agents to install on the managed nodes. After breathing a huge sigh of relief,
I dug around in the tool and found it makes for a great enterprise-level monitoring
solution. Did I mention that it's agent-less? I think you get the point, so
let's move on.
The Management Station is the central point of activity in Longitude. The entire
platform is Web-driven: a Java-based application running on top of a Tomcat
Web service. This means you can manage Longitude from anywhere just by contacting
the Management Station though the browser, anywhere on your network or the Internet,
if it's properly configured.
Secret Agent-less Man
The Management Station can passively connect to a number of operating systems
and application platforms, such as Windows 2000, 2003, XP, Linux, HP-UX, SunOS,
AIX, Oracle, SQL Server, MySQL, WebSphere, WebLogic, Apache, IIS and Exchange
Server. One thing I love about Longitude's approach is that it talks to systems
over standard protocols and interfaces, including HTTP/HTTPS, WMI, SSH, REXEC,
TELNET, JDBC, JMX and SNMP. In most cases, these interfaces are either available
by default on the systems you're going to be managing, or it's not a big deal
to install them. The point is that Longitude sticks to industry standards, which
I certainly appreciate.
Now, there is an agent in the box, but it's not for installing on the end nodes.
It works more like a DHCP relay agent or a bridgehead node. The Management Station
can direct the agent to collect statistical data from the remote managed systems
and bring it back to the Management Station.
This method works well when crossing domain or platform barriers. You can configure
security settings as tightly as necessary and still allow the appropriate level
of data gathering. This is a great feature, as it lets you shape the data stream
leading back to the Management Console in a more manageable fashion. When every
machine reports directly to the Management Station, it can create a lot of parallel
traffic over your network.
[Click on image for larger view.]
|Figure 1. Color-coded
displays give you a quick glance at factors like CPU performance and service
Installing Longitude was almost obscenely easy. Just install the tool on your
system and within a few short moments, you're looking at the Longitude interface
in your browser window. It's easy to get going with Longitude, another aspect
that improves its positioning among similar tools. With many utilities, you'll
have to spend time installing the tool and then rolling out the agents to manage
your target population. With Longitude, you're done in about 10 minutes.
One cool feature that's not necessarily new -- but is always worthy of mention
-- is correlated events. Essentially, you can set Longitude to flag an event
based on a mixture of different event conditions. You might say, for example,
"Alert me if Server 1's CPU exceeds 90 percent and disk space falls below
five percent availability." You may not care if the processor goes over
90 percent by itself, but if that disk goes below five percent availability
while the CPU is pegged you can have the system fire off an alert. To do so,
you'd configure Event Conditions and tie them to your correlated event.
You can also use correlated events to customize reporting. For example, you
can have the correlated event say that your project management group can't work
because their Web server carrying the PMIS is offline. You create the defined
event and use the correlated event to shape it as needed.
Longitude lets you monitor events to keep you in line with your Service Level
Agreements (SLAs). For example, if you agree that the database server will be
available 99.9 percent of the time with only one percent of degraded performance,
you can set the criteria for what is considered good and degraded performance.
Longitude will happily trend to see if you're meeting that requirement. This
is nice because it takes the subjectivity out of the equation and gives you
hard data by which to act on whether or not you're meeting your SLAs.
Stepping up from version 3.0 to 4.0, Heroix added more infrastructure monitoring
elements to Longitude. This means you can monitor things like Cisco routers,
DHCP servers, Active Directory, HP Insight and Dell OpenManage. Longitude has
a broad array of operating systems and applications it can manage. It seems
the folks at Heroix are always adding to that list, given that the tool first
rolled out in the Spring of 2005 and it's already up to version 4.0.
A centerpiece to the new version of Longitude is the consolidation of event
logs. A big concern for IT admins is mining through event logs to locate specific
incidents. It's a unique pain when you have to do that across numerous machines.
Longitude makes it easy to work through event log monitoring. It creates filters
you can use to sort through irrelevant events and focus on the ones you need
to see, regardless of the machine or platform on which the events happened.
Having events from a Unix box alongside Windows events is a nice feature and
truly unifies your system management efforts.
The only gotcha I could put a finger on with this tool is that it does like
to have a bit more RAM and processor on the Management Station. It needs 1GB
to install in production mode and a 2.4GHz processor is recommended. Nowadays,
though, with hardware priced as it is, this really should be a non-issue for
a current IT platform. Just know you can't skimp on the machine you choose to
run the Management Station.
Longitude relies on constant network connectivity to properly gather and report
on system data. The only real drawback to a passive monitor is that if something
prevents the machine from being monitored, like a network interruption, it will
directly affect the statistical data being fed into Longitude. That being the
case, Longitude probably isn't as appropriate for monitoring across remote or
temporary connections. Since it doesn't use end-node agents, it can't collect
data unless the Management Station can see the node. You can tweak the sampling
times in Longitude, but all things created equal, you can't monitor what you
[Click on image for larger view.]
|Figure 2. The statistics
dashboard shows performance data with several types of graphs.
Longitude is equipped with a nice array of reporting structures out of the
box. You can run reports on an ad-hoc basis or on a schedule for specific applications,
computers or departments based on how you've tagged the machines. You can create
dashboards that let you watch what's happening in near real time (the minimum
is 10 seconds). I did notice, however, that this level of monitoring is highly
performance-dependent, so if you're short on resources, this might not function
quite as well.
The fact that Heroix Longitude is agent-less is huge for me. In my opinion,
that's how a monitoring tool should operate. By not using agents, the monitored
machines aren't directly affected by the performance of the monitoring software.
The ability to create correlated events and reports and align to established
SLAs lets you use Longitude to map to business expectations quite effectively.
This level of visibility is available with very little intrusion or investment
of time, which makes Longitude well suited for anyone needing a no-nonsense
About the Author
Rick A. Butler, MCSE+I, is the Director of Information Services for the United States Hang Gliding Association.