Tools that are used to import operational state from our network into Netbox are typically called Discovery tools. Network Discovery typically falls into two categories:
- Network discovery - Scans a list of IPs or subnets to find any network devices in the network
- Device discovery - Logs into specific devices to extract their configurations
Slurp'it is a fully featured discovery tool. As the website says "If there’s a show command we can slurp’it!" Slurp'it can do network and device discovery across a large selection of network devices.
Let's slurp our network devices into Slurp'it using network discovery.
Tip
This section requires switching between Slurpit and NetBox, so double check which tool you should be using at the beginning of each section
Tip
To make sure your network is in the right state for this section, you can use the following command:
./3_start_network.sh network/4.1_discovery_reconciliation
Tip
Slurpit URL: ./0_set_envvars.sh | grep -i slurpit
username admin@admin.com
password 12345678
Slurpit provides a Device Finder that will scan a subnet to find network devices. This has already been configured in the lab to scan 172.24.0.0/24 which is where our ContainerLab devies are running. Navigate to Administrator -> Device Finder and then click on Start in the top right.
Now navigate to Devices -> Overview and after a short wait you'll see our lab devices have been discovered.
Now that Slurp'it has discovered our network devices, we need to onboard those devices into NetBox. The Slurp'it team have built a plugin for NetBox to help with this, so let's dive in.
Tip
NetBox URL: ./0_set_envvars.sh | grep -i netbox
username admin
password admin
First we need to configure the Slurpit plugin in NetBox. Most of this has been preconfigured, but there are a couple of manual steps we need to do ourselves.
Navigate to the NetBox left-hand menu and click on SLURP'IT -> Settings
Select BOTH from the Data Synchronization dropdown menu, and click Save
Now click in the Data tabs tab, click Sync, then check All and then hit Save
Now that the plugin is configured, navigate back to the NetBox left-hand menu and click on SLURP'IT -> Onboard devices
Tip
Slurpit syncs devices in the background, so your devices may already be populated
If you now click Sync the Slurp'it plugin will pull the devices it has discovered in our network over to NetBox.
Now select both clab-autocon2-srl1 and clab-autocon2-srl2 click on + Onboard. You'll see the Slurp'it device onboarding screen.
- Under
Management Interface*entermgmt0 - Under
Site*select theDenversite that was pre-populated in NetBox - Click
Applyat the bottom of the form
Now the devices in our network have been successfully imported into NetBox! You can confirm this by returning to the NetBox homepage and navigating to Devices -> Devices
With Slurpit, pulling discovered network data into Netbox happens in two stages. The first step, which we just did, is to onboard the devices. The second step is to Reconcile the additional data about the devices into NetBox, but first we need to discover that additional device data using Slurpit.
Tip
Slurpit URL: ./0_set_envvars.sh | grep -i slurpit
username admin@admin.com
password 12345678
In Slurpit navigate to Devices -> Overview and you'll see our lab devices. For both devices click on the ellipsis menu (three dots) on the far right side of device and click Schedule Now.
Slurp'it will take a short while to discover information about our devices. Then you can view the discovered information by clicking on the hostname on each device, and navigating to the Collected data tab. Feel free to explore the data Slurp'it has discovered about our devices. For example, under the Interfaces tab we can see the following:
Finally, we need to reconcile the discovered addtional device data into NetBox. We do this using the Slurpit NetBox plugin.
Tip
NetBox URL: ./0_set_envvars.sh | grep -i netbox
username admin
password admin
In the NetBox left-hand menu click on SLURP'IT -> Reconcile
Select the IPAM tab, select all the IPs and then click Accept.
Select the Interfaces tab, select all the interfaces and then click Accept
Now the device interfaces have been added to the devices in NetBox. To confirm, navigate to Devices -> Devices -> clab-autocon2-srl1 and select the Interfaces tab.
When we're getting started with intent-based network automation, the first important step is using discovery tools like Slurpit is populate our source of intent, NetBox. This gives us a baseline view of the network to compare against, but discovery tools have another purpose: detecting operational drift.
With our baseline view of the network in place, let's see how Slurpit can help us to detect operational drift, or differences between the network and our source of truth.
First need to introduce some operational drift, let's do that by making a change in the network by disabling ethernet-1/1 on clab-autocon2-srl1.
Tip
If you'd rather skip the manual steps, this command will prepare your network for the next practical section:
./3_start_network.sh network/4.2_discovery_reconciliation
Tip
username admin password NokiaSrl1!
ssh admin@clab-autocon2-srl1
enter candidate
interface ethernet-1/1 admin-state disable
interface ethernet-1/1 subinterface 0 ipv4 admin-state disable
commit now
Tip
Use Ctrl+Dto exit the Nokia SR Linux CLI
Tip
Slurpit URL: ./0_set_envvars.sh | grep -i slurpit
username admin@admin.com
password 12345678
This time instead of running the entire discovery, we can save ourselves a bit of time by just running discovery for interface details. Go to Dashboard the scroll down and under Task Scheduler click the > next to Ìnterfaces
Slurpit will now discover that the interface status for ethernet-1/1 on admin@clab-autocon2-srl1 has changed, and send it NetBox.
Now in NetBox
Tip
NetBox URL: ./0_set_envvars.sh | grep -i netbox
username admin
password admin
In the NetBox left-hand menu click on SLURP'IT -> Reconcile
Select the Interfaces tab, now you can see that Slurpit has found the operational drift. In this case you can see that in the Enabled column ethernet-1/1 now has cross next to it.
It's important to remember that when we discover operational drift, we don't always have to import it into NetBox.
In this case we decide that the source of truth is correct and the network is wrong. ethernet-1/1 on clab-autocon2-srl1 should be enabled, so there's an issue in the network and it should be fixed there.
In this case, select the item and hit Decline
Next Section - Monitoring - Icinga