Getting started with NAV

This tutorial will show you how to start monitoring devices with your brand new NAV installation.

The tutorial will refer to the web interface as http://example.org/ - replace this with whatever hostname you have configured for your NAV server.

Minimal configuration

All configuration files are located below /opt/nav/etc. Default configuration files are placed here on your first install. Most of these are documented with comments, so if you want to get advanced you can check each config file to see if there are any defaults you’d like to change.

We recommend you at least change the following two options in nav.conf before running NAV:

ADMIN_MAIL
Should be set to the NAV administrator’s e-mail address. Any cron mail or other administrative e-mails from NAV will be sent to this address.
DOMAIN_SUFFIX
The DNS domain name your devices are in. Many parts of the web interface will chop off this suffix to display abbreviated device names.
SECRET_KEY

A string of random characters that should be unique to each NAV installation. This is used by the Django framework for cryptographic signing in various situations. Here are three suggestions for generating a suitable string of random characters, depending on what tools you have available:

  1. gpg -a --gen-random 1 51
  2. makepasswd --chars 51
  3. pwgen -s 51 1

Please see https://docs.djangoproject.com/en/1.7/ref/settings/#std:setting-SECRET_KEY if you want to know more about this.

Starting NAV

NAV has two parts; one web frontend, and a backend consisting of multiple processes. While Apache serves the frontend, the backend processes can be controlled using the nav command (located in /opt/nav/bin).

The backend processes consist of some daemon processes, and some cron jobs. Running nav start will start all the daemon processes in the background, and install all the cron jobs in the navcron user’s crontab.

Depending on your OS of choice, you should configure it to run nav start on boot.

Logging in to the web interface

When browsing the web interface at http://example.org/ you will see the front page of NAV. This is openly accessible to anonymous users by default.

To log in for the first time, click the Login link on the upper right of the page, and enter the username “admin” and the default password “admin”. Then click the Userinfo link in the grey navigation bar and change the adminstrator’s password to something more sensible.

Seeding your database

NAV will not autodiscover the routers and switches of your network. You need to use the SeedDB tool to enter IP addresses to monitor. The SeedDB tool is listed on NAV’s Toolbox page, reachable from the grey navigation bar.

Adding your first device to NAV

The SeedDB tool enables to you add and edit a multitude of information in the NAV database, but the essential bit here is the IP Device. Begin, for example, by adding one of your switches:

  1. Click the IP device tab and then the sub-tab Add new IP device
  2. Fill out your switch’s IP address in the IP field, and, for now, select myroom and myorg in the room and organization drop-downs.
  3. Select SW in the category dropdown. Don’t worry, we’ll explain the categories later.
  4. Put your switch’s SNMP community in the Read only field and click the Check connectivity button.
../_images/seeddb-add-ipdevice.png

NAV will now check if this IP address responds to SNMP (v2c or v1) queries using the entered community and, if possible, detect the device’s type (from its sysObjectID value). NAV does not require that the connectivity test is successful, or even that the test is run, to add the device. But if the test fails this means that NAV can not communicate with the device. If that happens you should verify that the information in the IP and Read only fields is correct.

If you want you can add some free form text about the function of the device in the function field, put the device into one or more relevant groups and even assign custom attributes to it. These attributes will be used when NAV presents information about the device.

Click on Save IP device to finalize your entry of this device into NAV’s database.

Verifying that collection is working

Within two minutes, NAV’s SNMP collection engine should launch a job to poll your newly added device for information. The grey navigation bar features a search field; search for your newly entered device’s IP address or DNS name to show its IP Device Info page. The resulting page should look something like this:

../_images/ipdevinfo-switch-display.png

The IP Device Info page will try to display every bit of pertinent information about a monitored device. For now, the key information here is the Last updated field of the top-left detail panel. Keep reloading the page until its value changes from N/A into a meaningful timestamp.

Note

If no new information appears on this page within three minutes after adding your switch to NAV, you may need to start troubleshooting NAV’s log files.

Selecting a device category

When adding an IP device to NAV, you must select one of the predefined device categories:

GW
Your basic layer 3 router
GSW
An L3 switch (a routing switch)
SW
A regular switch
EDGE
An edge switch. Use this category only if you do not want NAV to collect traffic statistics from its switch ports.
SRV
A server.
WLAN
A wireless access point or controller of some sort.
ENV
An environmental probe, possibly measuring temperatures, humiditiy, etc. If NAV has support for the probe, its measurements will be displayed in the room view for the room the device was registered in.
POWER
Power distribution and measurement equipment, UPS units and so forth.
OTHER
Any other type of device not fitting neatly into the other categories.

All categories will require an SNMP community to be configured, except for SRV and OTHER, where it is optional.

Importing multiple devices in bulk

While you can go ahead and add one device at a time like this, it will quickly get tedious if you have more than a handful of devices to monitor. This is where the Bulk import function comes into the picture:

../_images/seeddb-bulkimport-ipdevice.png

Assuming you have a readily available list of IP addresses to monitor, you can create a comma (or colon) separated text file with the required details and upload or paste it into the bulk import form.

The format is pretty straightforward: The initial fields are required, while the fields listed in square brackets are optional. Optional fields can be omitted or left blank. A line beginning with a # sign will be regarded as a comment and ignored. Thus, for adding some switch with the SNMP community public and a function description of Packet switching, this line would do it:

myroom:10.0.1.42:myorg:SW:public:::Packet switching

Click Preview import to have NAV validate your input. Each line will be displayed with colored status dot. A green dot indicates the line was found OK and will be imported once you submit. A yellow or red dot indicates an error with the line; such a line will be ignored when you submit the preview form, unless you go back and fix it before trying again.

Further reading

Now you know how to monitor things. It’s time to get organized!