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Home Documentation Junos OS Junos CLI Reference CLI Reference M

Junos CLI Reference

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monitor security packet-drop

date_range 19-Nov-23
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Syntax

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monitor security packet-drop
<source-prefix>
<destination-prefix>
<source-port>
<destination-port>
<ingress-interface-name>
<protocol>
<logical-system-name>
<count-number>

Description

Displays the packet-drop information without committing the configuration, which allows you to trace and monitor the traffic flow. This command output is displayed on the screen until you press Ctrl+c or until the security device collects the requested number of packet drops. The command includes various filters to generate the output fields per your requirement.

You can save the packet pocket records to a file using the monitor security packet-drop | append /var/log/filename.log command.

Options

source-prefix

Display the packet drop information for the given source IP or source prefix address.

destination-prefix Display the packet drop information for the given destination IP or source prefix address.
source-port Display the packet drop information for the given source port.
destination-port Display the packet drop information for the given destination port.
ingress-interface-name Display the packet drop information for the given ingress interface address.
protocol Display the packet drop information for the given protocol number.
logical-system-name Display the packet drop information for the logical system name.
count-number Display the packet drop information for the given count.

Range: 1 thru 8000

Default: 50

Required Privilege Level

view

Sample Output

monitor security packet-drop

When configuration is set to default IDP security policy, using the command set security idp idp-policy IDP_Default rulebase-ips rule 1 then action drop-packet, the following type of output is displayed for monitor security packet-drop command.

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user@host> monitor security packet-drop
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Starting packet drop:
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:IDP drop SLL packet

When configuration is set to drop connection action, the following type of output is displayed for monitor security packet-drop command.

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user@host> monitor security packet-drop
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Starting packet drop:
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:Malformed IPV6 header in IPv4 tunnel
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:Bad TCP headers

Output for packet drops independent of IPS policies.

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user@host> monitor security packet-drop
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Starting packet drop:
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:IDP drop SLL packet
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:Malformed IPV6 header in IPv4 tunnel
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:Bad TCP headers
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:Overflow drops
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:Sequence number wrap around errors
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:IDP Policy Initn failed
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:Flow Rejected
Output for packet drops dependent on IPS policies.
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user@host> monitor security packet-drop
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Starting packet drop:
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:IDP Rule Action Drop Packet ICMP:INFO:ECHO-REQUEST
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:IDP Rule Action Close-Client-And-Server ICMP:INFO:ECHO-REQUEST
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:IDP Rule Action Close-Server ICMP:INFO:ECHO-REQUEST
14:46:45.511471:LSYS-ID-00 4.0.0.1/19895-->5.0.0.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:IDP Rule Action Close-Client ICMP:INFO:ECHO-REQUEST

monitor security packet-drop with filters

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user@host> monitor security packet-drop source-prefix 192.0.2.1 destination-prefix 192.151.100.1 proto icmp
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14:46:45.511471:LSYS-ID-00 192.0.2.1/19895-->192.151.100.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:IDP Rule Action Close-Server ICMP:INFO:ECHO-REQUEST
14:46:45.511471:LSYS-ID-00 192.0.2.1/19895-->192.151.100.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:IDP Rule Action Close-Client ICMP:INFO:ECHO-REQUEST

monitor security packet-drop count 2

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user@host> monitor security packet-drop count 2
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14:46:45.511471:LSYS-ID-00 192.0.2.1/19895-->192.151.100.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:IDP Rule Action Close-Server ICMP:INFO:ECHO-REQUEST
14:46:45.511471:LSYS-ID-00 192.0.2.1/19895-->192.151.100.1/1;icmp,ipid-0,ge-0/0/0.0,Dropped by IDP:IDP Rule Action Close-Server ICMP:INFO:ECHO-REQUEST

monitor security packet-drop | append /var/log/abcd.log

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user@host> monitor security packet-drop | append /var/log/abcd.log
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^C[abort]
Wrote 7 lines of output to '/var/log/abcd.log'

show log abcd.log

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user@host> show log abcd.log
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Starting packet drop:
07:35:36.742809:LSYS-ID-00 192.0.2.1/2198-->192.151.100.1/1;icmp,ipid-16088,ge-0/0/2.0,Dropped by POLICY:Denied by Policy: default-policy-logical-system-00
07:35:37.640858:LSYS-ID-00 192.0.2.1/2198-->192.151.100.1/2;icmp,ipid-52440,ge-0/0/2.0,Dropped by POLICY:Denied by Policy: default-policy-logical-system-00
07:35:38.665155:LSYS-ID-00 192.0.2.1/2198-->192.151.100.1/3;icmp,ipid-28633,ge-0/0/2.0,Dropped by POLICY:Denied by Policy: default-policy-logical-system-00
07:35:39.689185:LSYS-ID-00 192.0.2.1/2198-->192.151.100.1/4;icmp,ipid-47577,ge-0/0/2.0,Dropped by POLICY:Denied by Policy: default-policy-logical-system-00
07:35:40.712870:LSYS-ID-00 192.0.2.1/2198-->192.151.100.1/5;icmp,ipid-44762,ge-0/0/2.0,Dropped by POLICY:Denied by Policy: default-policy-logical-system-00
07:35:41.797742:LSYS-ID-00 192.0.2.1/2198-->192.151.100.1/6;icmp,ipid-16859,ge-0/0/2.0,Dropped by POLICY:Denied by Policy: default-policy-logical-system-00

Release Information

Command introduced in Junos OS Release 21.1R1.

Signature added to packet drop reason in Junos OS Release 21.2R2.

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