examine-dhcp
Syntax
(examine-dhcp | no-examine-dhcp);
Hierarchy Level
[edit ethernet-switching-options secure-access-port vlan (all
| vlan-name)]
Release Information
Statement introduced in Junos OS Release 9.0 for EX Series switches.
Description
Enable DHCP snooping on all VLANs or on the specified VLAN.
- examine-dhcp—Enable DHCP snooping.
- no-examine-dhcp—Disable DHCP snooping.
When DHCP snooping is enabled, the switch logs DHCP packets (DHCPOFFER, DHCPDECLINE, DHCPACK, and DHCPNAK packets) that it receives on untrusted ports. You can monitor the log for these messages, which can signal the presence of a malicious DHCP server on the network.
![]() | Tip: For Private VLANs (PVLANs), enable DHCP snooping on the primary VLAN. If you enable DHCP snooping only on a community VLAN, DHCP messages coming from PVLAN trunk ports are not snooped. |
Default
Disabled.
Required Privilege Level
routing—To view this statement in the configuration.
routing-control—To add this statement to the configuration.
Related Topics
- Example: Configuring Port Security, with DHCP Snooping, DAI, MAC Limiting, and MAC Move Limiting, on an EX Series Switch
- Example: Configuring DHCP Snooping, DAI , and MAC Limiting on an EX Series Switch with Access to a DHCP Server Through a Second Switch
- Example: Configuring DHCP Snooping and DAI to Protect the Switch from ARP Spoofing Attacks
- Enabling DHCP Snooping (CLI Procedure)
- Enabling DHCP Snooping (J-Web Procedure)

