Configuring Packet Capture On An Interface (Required); Configuring A Firewall Filter For Packet Capture (Optional) - Juniper J-Series Administration Manual

Configuring Packet Capture on an Interface (Required)

To capture all transit and host-bound packets on an interface and specify the direction
of the traffic to capture—inbound, outbound, or both:
1.
2.
3.
4.
Table 135: Configuring Packet Capture on an Interface
Task
Navigate to the Interfaces level in the
configuration hierarchy, and select
an interface for packet capture—for
example, fe-0/0/1 .
(See the interface naming
conventions in the J-series Services
Router Basic LAN and WAN Access
Configuration Guide.)
Configure the direction of the traffic
for which you are enabling packet
capture on the logical interface—for
example, inbound and outbound.
NOTE: Packets originating from the host router are not captured unless you have
configured and applied a firewall filter on the interface in the output direction.

Configuring a Firewall Filter for Packet Capture (Optional)

To configure a firewall filter and apply it to the logical interface:
Navigate to the top of the configuration hierarchy in either the J-Web or CLI
configuration editor.
Perform the configuration tasks described in Table 135 on page 259.
If you are finished configuring the router, commit the configuration.
Go on to one of the following procedures:
To configure a firewall filter, see "Configuring a Firewall Filter for Packet
Capture (Optional)" on page 259.
To check the configuration, see "Verifying Packet Capture" on page 263.
J-Web Configuration Editor
1. In the J-Web interface, select
Configuration>View and Edit>Edit
Configuration.
2. Next to Interfaces, click Configure or
Edit.
3. In the Interface name box, click
fe-0/0/1.
1. In the Interface unit number box,
click 0.
2. Next to Inet, select Yes, and click
Edit.
3. Next to Sampling, click Configure.
4. Next to Input, select Yes.
5. Next to Output, select Yes.
6. Click OK until you return to the
Interface page.
Configuring Packet Capture with a Configuration Editor
Chapter 13: Configuring Packet Capture
CLI Configuration Editor
From the hierarchy level, enter
[edit]
edit interfaces fe-0/0/1
Enter
set unit 0 family inet sampling input output
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