3.2
Devices
Servers, routers, switches, desktops, workstations,
appliances, every piece of hardware in the network is managed within AutoNOC using the
powerful Device object.3.2.1
Device Hierarchy
Devices in AutoNOC are broken down into a
hierarchy of children including a category, components, and individual probes or logs that
are related to the specific parent component and category. For instance, consider a
traffic monitor called Total Traffic for a network interface card. In this case
you have a device category called Interfaces and a component for the interface.
In the following picture, the interface is called eth1 - WAN (this picture is
from a Linux server setup to be a router in case you were wondering).
In summary, we have the
following objects making up the hierarchy for a given monitored device.
- Device
The root object for the device.
- Category
All sub-objects of a device are broken down into categories. For instance
"Interface" would be one category as would "Storage" or
"Memory".
- Component
Every category is further broken down into components which represent the
available instances of items related to the category. For example, the
"Interface" category would contain all the specific instances of interfaces for
the device.
- Probes and Logs
Each component is then broken down further by probes and logs that work
with the component.
This architecture is useful in that it
allows AutoNOC to adapt to any conceivable capabilities of a device while maintaining a
simple hierarchical view of the device that can be easily put to work in terms of the
analytical features. Other products and standards have approached this problem in more
complex ways with large, inconsistent inter-device structures.
AutoNOC's core operations model can
support the more complex ways of managing devices if we ever needed to, but the current
category and component device model has proven a winner with customers and has simplified
drilldown related analysis significantly.
At first glance, this tree probably
seems extremely large and cumbersome for a user to maintain. Do not worry! AutoNOC
maintains this tree for you. The category and component definitions are actually defined
by the specific logs and probe templates during discovery, so the only changes you would
ever make to the device hierarchy are generic ones to apply to all devices utilizing
specific probes.
3.2.2 Links Between Devices
Just like the real world, AutoNOC supports component level
linking between devices. For example, in AutoNOC you link an interface component to
another interface component, just like the actual hardware works.
AutoNOC tries to detect links automatically when doing
device discoveries, but the links can be user configured as well. The actual configuration
of the link is done on interface components on the Link page as shown in the
following picture.
When AutoNOC discovers a device that does
not have SNMP or an equivalent management protocol available to identify interfaces on the
device, it will create an object of the name Unknown Interface. This object is
created to make it easy to build links between devices.
3.2.3 Device Discovery Guide
One of the very first things you are likely to do with AutoNOC is to add devices. Creating
devices in AutoNOC is in fact very easy, but this guide is useful in helping you to
understand all of the details.
Why do you need to create devices?
AutoNOC's principle management functionality is built around the management and monitoring
of core operational devices. The operations model is built by creating, designing, and
customizing the monitoring of devices.
When AutoNOC discovers a device it
automatically constructs the device hierarchy tree for you. You are free to modify the
tree and prune branches to change the monitoring behavior of the device, but you don't
necessarily have to.
Device Discovery Steps
The following steps are a walk through in creating and defining devices:
Step 1:
Create and Discover Device(s)
Adding and discovering devices in AutoNOC is very easy. To get started, click on the root Devices
object (or a folder underneath this root) and then click on Create and Discover
Devices. AutoNOC will open up the device discovery dialog box.
This dialog has the following options:
- Device Template
Specify (Automatic) or a specific template to use when
discovering devices. If automatic is chosen, then AutoNOC will use the settings in each
device template to try and see which template is most appropriate for the device. When a
specific template is chosen, it will be forced on the device and will use the settings for
the chosen template.
- Destination Folder
Specifies the folder to store the discovered devices in.
- IP Address(s) or Host Name(s)
Enter a list of IP addresses or host names (that AutoNOC will try and
resolve) for the devices to be discovered. AutoNOC will create a new device for each
entry.
- SNMP Community(s)
List the SNMP community names for the devices. AutoNOC will test each
device with the SNMP community names listed to try and find matches.
Fill in the fields with IP addresses and
community names for your network and then start the discovery.
Step
2: Modify Device Template
It will take a few minutes for AutoNOC to discover the device. Wait for a minute and then
click on one of the new devices to open the device dialog box for it.
Changing device templates is not
necessary, and in fact, in most cases you will not need to make any changes to the
templates, but it useful to look at how AutoNOC uses device templates in the software.
Every device can optionally get a
variety of settings from a Device Template. AutoNOC includes a large number of
built in templates and the user can create their own. Click on the Template tab
to see the name of the template that the device is using. Devices don't necessarily have
to use a template but if they do they can take advantage of a number of presets including
which probes and interfaces will be discovered on the device.
To modify the settings for the template
(which will be shared by all devices using the template) find the template in the Templates/Devices
folder. Some of the settings that are stored within the template include:
- Manufacturer, Model, and Type
Customizable device identification information for devices that make use
of this template.
- Allowed Components, Interfaces,
and Probes
When discovering the device, the template controls which components,
interfaces, and probes AutoNOC will use for the device.
If needed, make any modifications to the
template or templates for the devices. These changes will come into play when discovering
future devices that use this template or when utilizing automated maintenance features.
Step 3:
Specify User Category If Any
AutoNOC allows the user to specify a user category for a device. This could be an internal
organization designation for the device of some sort.
If you would like to change this field,
click on the device object, then the Information tab and provide the custom user
description text.
Step 4:
Modify Primary IP and Polling Expression
Every device has two kinds of IP addresses. There is the primary IP address and there are
IP addresses specified for devices. The primary IP address is specified in the device
itself and the interface IP is specified for each interface component. When acquiring
data, which IP address is used is dependent on the expression variable defined in the
probes acquisition expression. In general, the primary IP is the one that will be used the
most and it is the one used for discovery on the device.
If you would like to change the primary
IP address for the device, it can be changed on the Acquisition tab of the device
in the Primary IP field.
AutoNOC also supports user defined
polling expressions that deterine how often the software will attempt to acquire data from
the device (poll it). By default, AutoNOC defines this as "60" meaning every 60
seconds. It is however possible to change this to an expression that will be evaluated
dynamically. For instance, an expression like if(%CURRENTLEVEL<0,60,300) which
would poll the device once every 5 minutes if there are no problems, but once every 60
seconds if there was a problem.
Step 5:
Enable/Disable Device Logs
AutoNOC can maintain various logs for a given device. Some of the logs that can be enabled
or disabled include:
- SNMP Trap Log
Logs all traps the device receives.
- Syslog Log
Allows logging of incoming syslog events for this device.
- State Change Log
Logs state changes that occur for any of the probes. This is very useful
for the Observe tab.
All of these logs can be enabled or
disabled on the Acquisition tab of the device.
Step 6: Specify
SNMP Read Community
Typically AutoNOC will fill in the SNMP read community name during discovery. But just in
case it changes or has to be modified for some reason, this value can be changed on the SNMP
tab of the device. Change it if necessary.
Step 7:
Monitor Device Stacks
AutoNOC uses device stacks for the handling of the complex state information related to
acquiring data. Device stacks can be very useful in terms of evaluating what AutoNOC is
doing with the device. The device stacks are presented on the Stacks tab of the
device. Note that they are only updated when the device dialog box is opened, so to
refresh them you must close and then open the dialog box again. |
