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Dynamic Host Configuration Protocol (DHCP) Snooping is a security feature that acts as a firewall between untrusted hosts and trusted DHCP servers. It helps prevent malicious or malformed DHCP traffic by monitoring DHCP messages and filtering untrusted sources.

When configuring DHCP Snooping on RUCKUS ICX switches, consider the following:

Global Enablement: DHCP Snooping must be enabled globally on the switch to activate the feature across the device. This is done using the following command in global configuration mode:

ip dhcp snooping

Trusted Interfaces: Interfaces connected to legitimate DHCP servers should be configured as trusted to allow DHCP server messages to pass through. This is configured per interface:

interface ethernet 1/1/1

ip dhcp snooping trust

Replace 1/1/1 with the appropriate interface identifier.

VLAN Configuration: DHCP Snooping must be enabled on specific VLANs where DHCP services are required. This ensures that DHCP messages are monitored within those VLANs:

Understanding CLI Levels:

The ping command is used to test connectivity to other devices by sending ICMP echo requests.

It can only be executed from the privileged EXEC mode, which is indicated by the Router# prompt.

Why Other Prompts Don't Work:

A. Router(config-if-mgmt-1)#: This is the interface configuration mode for the management port and does not allow execution of diagnostic commands like ping.

B. Router(config)#: This is the global configuration mode, which is used to configure the switch but does not support diagnostic commands.

D. Router(config-if-e1000-1/1/1)#: This is the interface configuration mode for Ethernet 1/1/1, which also does not allow execution of ping.

References:

RUCKUS ICX CLI Guide: RUCKUS Documentation

To configure a RUCKUS ICX 7750 switch to honor Differentiated Services Code Point (DSCP)-based Class of Service (CoS) at the interface level, the trust dscp command is used. This command instructs the switch to trust and utilize the DSCP values in incoming packets for Quality of Service (QoS) decisions.

Configuration Steps:

Access the Switch's Command Line Interface (CLI):

Use SSH or a direct console connection to access the switch's CLI.

Enter Global Configuration Mode:

At the prompt, enter:

enable

configure terminal

Select the Interface to Configure:

Specify the interface where DSCP trust should be enabled. For example, to configure Ethernet interface 1/1/1:

interface ethernet 1/1/1

RSTP and Legacy 802.1D Compatibility:

RSTP (802.1w) can interoperate with legacy switches running STP (802.1D). However, the legacy switches use different timers and convergence mechanisms, which can lead to delays.

Optimizing Timers for Legacy Edge Switches:

The edge switches running 802.1D rely on BPDU timing set by the upstream aggregation switches.

To influence the convergence time, the timers such as hello time, max age, and forward delay must be adjusted on the aggregation switches connected to these legacy edge switches. This ensures better compatibility and faster convergence.

Why Not Other Options?

A: The route-only port does not participate in STP.

B: Timers cannot be modified on legacy switches themselves as they strictly follow 802.1D standards.

D: The root bridge sets global parameters but does not address edge-specific timer optimization.

References:

RUCKUS RSTP/802.1D Compatibility Guide: RUCKUS Documentation

In RUCKUS ICX switches, VLAN 1 is the default VLAN and is typically used for management purposes. By default, all ports are members of VLAN 1 as untagged. Attempting to configure VLAN 1 as tagged on a port can result in an error, as the system restricts tagging the default VLAN.

Understanding the Error:

RKUS-01(config)# vlan 1

RKUS-01(config-vlan-1)# tagged ethernet 1/2/1

Invalid input -> tagged ethernet 1/2/1

Type ? for a list

This error occurs because the switch does not allow tagging of the default VLAN (VLAN 1) on any interface.

Resolution:

Option 1: Use a Different VLAN for Tagging

Create a new VLAN (e.g., VLAN 2) and configure it as tagged on the desired port.

RKUS-01(config)# vlan 2

RKUS-01(config-vlan-2)# tagged ethernet 1/2/1

Option 2: Change the Default VLAN ID

If you must use VLAN 1 as tagged, you can change the default VLAN ID to another VLAN (e.g., VLAN 2), allowing VLAN 1 to be configured as tagged.

RKUS-01(config)# default-vlan-id 2

RKUS-01(config)# vlan 1

RKUS-01(config-vlan-1)# tagged ethernet 1/2/1

Class of Service (CoS) and Differentiated Services Code Point (DSCP) are both mechanisms used to prioritize network traffic, but they function at different layers of the OSI model and have distinct characteristics:

Operational Layer:

CoS:

Operates at Layer 2 (Data Link Layer) of the OSI model.

Utilizes a 3-bit field within the 802.1Q VLAN tag, known as the Priority Code Point (PCP), to assign priority levels ranging from 0 to 7.

DSCP:

Operates at Layer 3 (Network Layer) of the OSI model.

Uses a 6-bit field in the IP header to assign priority, allowing for up to 64 different values, providing more granularity in traffic classification.

Scalability and Complexity:

CoS:

With only 8 possible priority levels, CoS offers limited granularity.

As network demands increase, especially with diverse applications requiring different levels of service, managing and differentiating traffic with CoS can become complex due to its limited priority levels.

DSCP:

Provides 64 distinct priority levels, allowing for finer differentiation of traffic types.

This granularity enables easier scalability and more straightforward management of diverse and growing network traffic demands.

References:

For a detailed comparison between CoS and DSCP, refer to the NetworkLessons Notes on QoS CoS vs DSCP: QoS CoS vs DSCP - NetworkLessons Notes

For an overview of Differentiated Services and traffic classification, see the article on GeeksforGeeks: Differentiated Services (DiffServ) and Traffic Classification

Understanding these differences is crucial for network administrators when designing Quality of Service (QoS) policies to ensure efficient and effective traffic management across the network.

Adding a new member to an existing RUCKUS ICX switch stack can be accomplished through the following methods:

Stack Priority Configuration:

Determine the role of the new switch within the stack hierarchy by setting its priority.

Access the new switch's CLI.

Enter global configuration mode: configure terminal.

Set the stack unit ID and priority: stack unit [unit_id] priority [priority_value].

A higher priority value increases the likelihood of the switch becoming the stack master.

Save the configuration: write memory.

Manual Configuration:

Manually configure the new switch to match the existing stack settings.

Ensure the switch has a clean configuration by resetting it to factory defaults:

Enter global configuration mode: configure terminal.

Execute: write erase.

Reload the switch: reload.

Enable stacking:

Enter global configuration mode: configure terminal.

Execute: stack enable.

Connect the new switch to the existing stack using appropriate stacking cables.

On the stack master, use the stack secure-setup command to recognize and add the new member.

Verify the new member's addition by executing: show stack.

References:

For detailed procedures on building an ICX stack, refer to the RUCKUS Community Forums.

Ruckus Wireless Community

Power over Ethernet (PoE) technology allows network switches to deliver electrical power to connected devices over standard Ethernet cables. The IEEE 802.3at standard, commonly known as PoE+, provides up to 30 watts of power per port. RUCKUS enhances this capability with a proprietary feature called PoE+ Overdrive, which increases the maximum power output per port.

With PoE+ Overdrive enabled, a PoE+ interface on RUCKUS ICX switches can deliver up to 45 watts of power over two pairs of wires. This enhancement is particularly beneficial for devices that require more power than the standard PoE+ provision, such as advanced wireless access points or video conferencing systems.

It's important to note that the actual power delivered to the powered device (PD) is slightly less due to cable losses. For instance, while the Power Sourcing Equipment (PSE) may supply 45 watts, the PD might receive approximately 35.5 watts. This ensures that devices receive sufficient power even after accounting for transmission losses.

The availability of PoE+ Overdrive and the maximum power output per port can vary depending on the specific ICX switch model. For example, the RUCKUS ICX 7650 supports PoE+ Overdrive with a maximum output of 45 watts per port. Similarly, the ICX 7150-48ZP model offers PoE+ Overdrive capabilities.

For detailed information on PoE+ Overdrive capabilities and supported models, refer to the "Ruckus Power over Ethernet (PoE) Interoperability" document.

Zero-touch stacking simplifies the process of forming a stack by automating the configuration. To ensure all devices join the stack seamlessly, the following prerequisites must be met:

Enable Stacking on All Devices:

Access each switch's CLI.

Enter global configuration mode: configure terminal.

Enable stacking by executing: stack enable.

Save the configuration with: write memory.

Ensure Units Have Clean Configurations:

It's crucial that switches have default configurations to prevent conflicts during the stacking process.

To reset a switch to its default settings:

Enter global configuration mode: configure terminal.

Execute the command: write erase.

Reload the switch to apply the default configuration: reload.

Additional Considerations:

Ensure all switches are running compatible firmware versions to prevent software mismatches.

Verify that stacking cables are correctly connected to facilitate proper communication between units.

References:

For a comprehensive guide on building an ICX stack using zero-touch provisioning, consult the RUCKUS Community Forums.

To monitor and manage the PoE power budget on RUCKUS ICX switches, the following commands are utilized:

show inline power Command:

Purpose: Displays a summary of the PoE status, including total power capacity, power consumption, and available power.

Usage:

Access the switch's command-line interface (CLI).

Enter the command:

plaintext

Copy code

show inline power

Output Details:

Power Capacity: Total PoE power available on the switch.

Power Allocations: Power consumption per port, indicating which ports are supplying power to connected devices.

Example Output:

plaintext

Copy code

Power Capacity: Total is 124000 mWatts. Current Free is 64000 mWatts.

Power Allocations: Requests Honored 8 times

Port Admin Oper ---Power (mWatts)--- PD Type PD Class Pri Fault/

State State Consumed Allocated Error

-----------------------------------------------------------------------------

1/1/1 On On 4733 30000 2P-IEEE Class 4 3 n/a

1/1/2 On Off 6015 30000 2P-IEEE Class 4 3 n/a

(additional ports)