Cisco Systems 3750 guide

Chapter 3 Message and Recovery Procedures

DHCP_SNOOPING Messages

Error Message DHCP_SNOOPING-4-NTP_NOT_RUNNING: NTP is not running; reloaded binding lease expiration times are incorrect.

Explanation If the DHCP snooping database agent loads the DHCP snooping bindings and NTP is not running, the calculated lease duration for the bindings is incorrect.

Recommended Action Configure NTP on the switch to provide an accurate time and date for the system clock. Then disable and re-enable DHCP snooping to clear the DHCP snooping binding database.

Error Message DHCP_SNOOPING-4-QUEUE_FULL: Fail to enqueue DHCP packet into

processing queue: [chars], the queue is most likely full and the packet will be dropped.

Explanation The CPU is receiving DHCP at a higher rate than the DHCP snooping can process. These DHCP packets are dropped to prevent a denial of service attack. [chars] is the warning.

Recommended Action No action is required.

Error Message DHCP_SNOOPING-4-STANDBY_AGENT_OPERATION_FAILED: DHCP snooping binding transfer failed on the Standby Supervisor. [chars].

Explanation The DHCP snooping binding transfer process failed on a standby supervisor engine. [chars] is the standby supervisor engine.

Recommended Action No action is required.

Error Message DHCP_SNOOPING-5-DHCP_SNOOPING_UNTRUSTED_PORT: DHCP_SNOOPING drop

message on untrusted port, message type: [chars], MAC sa: [enet]

Explanation An untrusted port dropped a DHCP message. A host might be acting as a DHCP server. [chars] is the message type (DHCPOFFER, DHCPACK, DHCPNAK, or DHCPLEASEQUERY), and [enet] is the MAC address of the sending host.

Recommended Action No action is required.

Error Message DHCP_SNOOPING-6-AGENT_OPERATION_SUCCEEDED: DHCP snooping database [chars] succeeded.

Explanation The DHCP binding transfer process succeeded. [chars] is the DCHP snooping database.

Recommended Action No action is required.

Error Message DHCP_SNOOPING-6-BINDING_COLLISION: Binding collision. [dec] bindings ignored.

Explanation The specified number of bindings were ignored when the switch read the database file. The bindings from the database file have MAC address and VLAN information that a configured DHCP snooping binding already uses.

Recommended Action No action is required.

Catalyst 3750, 3560, 3550, 2975, 2970, and 2960 Switch System Message Guide

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Cisco Systems 3750 manual Message and Recovery Procedures Dhcpsnooping Messages

3750 specifications

The Cisco Systems 3750 series is a family of enterprise-class stackable switches that were designed to provide high-performance networking solutions for organizations requiring robust management features, security, and scalability. Known for their reliability and advanced capabilities, the 3750 series is particularly aimed at accommodating the demands of LAN environments in organizations ranging from small businesses to large enterprises.

One of the defining features of the Cisco 3750 series is its StackWise technology. This innovative feature enables the stacking of up to nine switches together, allowing them to function as a single logical unit. This results in simplified management, higher redundancy, and increased scalability. The StackWise technology allows for seamless failover and enhanced bandwidth between the stacked switches.

In terms of performance, the 3750 series supports Layer 2 and Layer 3 switching, offering routing capabilities to handle both traditional and modern network demands. It is equipped with advanced Quality of Service (QoS) features, ensuring that critical applications such as voice and video are prioritized for optimal performance.

The Cisco 3750 also features extensive security capabilities. It incorporates features such as IEEE 802.1X authentication, DHCP snooping, and dynamic ARP inspection to protect against unauthorized access and various network attacks. These enhancements help maintain data integrity and secure communications across the network.

Another noteworthy characteristic of the 3750 series is its support for Power over Ethernet (PoE). PoE allows for the delivery of power over Ethernet cables to connected devices, such as IP phones and wireless access points, facilitating simpler installations and reducing the need for additional power outlets.

The Cisco 3750 series also provides a comprehensive set of management tools. With features like Cisco's Embedded Event Manager (EEM) and extensive SNMP support, network administrators can efficiently monitor and manage network performance, troubleshoot issues, and maintain high availability.

Additionally, the series is compatible with Cisco's IOS software, which provides a rich set of features, including advanced routing protocols, multicast support, and extensive security options, further enhancing the functionality and versatility of the switches.

Overall, the Cisco Systems 3750 series stands out for its stackable design, high-performance features, security capabilities, and management tools, making it a popular choice for organizations looking for dependable and scalable networking solutions.