Administrator Guide

Defaults none
Command Modes
• EXEC
• EXEC Privilege
Command History
This guide is platform-specific. For command information about other platforms, refer to the relevant Dell
Networking OS Command Line Reference Guide.
The following is a list of the Dell Networking OS version history for this command.
Version Description
9.9(0.0) Introduced on the C9010.
9.2(1.0) Introduced on the Z9500.
8.3.19.0 Introduced on the S4820T.
8.3.11.1 Introduced on the Z9000.
8.3.7.0 Introduced on the S4810.
7.8.1.0 Introduced on the C-Series and S-Series.
Related
Commands
clear ip dhcp snooping — clears the contents of the DHCP binding table.
ICMP Vulnerabilities
The internet control message protocol (ICMP) is a network-layer internet protocol that provides message packets to report errors and
other information regarding IP packet processing back to the source. Dell Networking OS mainly addresses the following ICMP
vulnerabilities:
• ICMP Mask Reply
• ICMP Timestamp Request
• ICMP Replies
• IP ID Values Randomness
You can configure the Dell Networking OS to drop ICMP reply messages. When you configure the drop icmp command, the system
drops the ICMP reply messages from the front end and management interfaces. By default, the Dell Networking OS responds to all the
ICMP messages. You can configure the Dell Networking OS to suppress the following ICMPv4 and ICMPv6 message types:
Table 11. Suppressed ICMPv4 message types
ICMPv4 Message Types
Echo reply (0)
All sub types of destination unreachable (3)
Source quench (4)
Redirect (5)
Router advertisement (9)
Router solicitation (10)
Time exceeded (11)
IP header bad (12)
Timestamp request (13)
Timestamp reply (14)
Information request (15)
Information reply (16)
Address mask request (17)
Address mask reply (18)
Security 1465