350-601 Exam Dumps - Implementing Cisco Data Center Core Technologies (350-601 DCCOR)

 In an FCoE environment, the PAUSE mechanism is used to provide lossless behavior for Fibre Channel traffic over Ethernet. The PAUSE mechanism allows a receiver to send a PAUSE frame to a sender when its ingress buffer is full or close to full, instructing the sender to stop transmitting for a specified period of time. This prevents packet loss due to buffer overflow at the receiver. However, the PAUSE mechanism also introduces latency and jitter, which can affect the performance of FCoE applications. Therefore, the receiver must provision sufficient ingress buffer to accommodate the following two sets of data12:

• Frames that were processed and transmitted by the transmitter before the PAUSE frame left the sender. These frames are already on the wire and cannot be stopped by the PAUSE frame. They will arrive at the receiver and consume ingress buffer space.
• Frames that were sent on the link but not yet received. These frames are also on the wire and will arrive at the receiver after the PAUSE frame. They will also consume ingress buffer space.

The amount of ingress buffer required depends on the link speed, the link distance, and the PAUSE duration. The receiver must ensure that the ingress buffer can hold at least twice the link distance worth of data, plus some margin for safety3. For example, if the link speed is 10 Gbps, the link distance is 10 km, and the PAUSE duration is 100 microseconds, the receiver must have at least 25 MB of ingress buffer for each FCoE virtual lane4.

References := 1: Nexus 7000 F2/F2e Ingress Buffer modifications for FCoE MultiHop over long distance - Cisco 2: Cisco Nexus 7000 Series FCoE Configuration Guide 3: In an FCoE environment, for which two sets of data must an interface that implements the PAUSE mechanism always provision sufficient ingress buffer? (Choose two) 4: Fibre Channel over Ethernet (FCoE) - Cisco

Two capabilities of the Cisco Network Assurance Engine are that it validates that devices comply with network security policies and that it predicts the impact of changes to the network. The Cisco Network Assurance Engine is a software solution that uses mathematical modeling and verification techniques to continuously analyze the state and configuration of the data center network. It can validate that the network devices are compliant with the intended security policies, such as access control lists, firewall rules, and encryption standards. It can also predict the impact of planned or unplanned changes to the network, such as software upgrades, configuration changes, or device failures, and provide proactive recommendations to avoid or resolve issues. The Cisco Network Assurance Engine helps to ensure that the network is always operating as intended and aligned with the business objectives. References :=

• Implementing and Operating Cisco Data Center Core Technologies (DCCOR) v1.2, Module 8: Data Center Automation and Orchestration, Lesson 8.4: Cisco Data Center Network Assurance and Insights
• Cisco Network Assurance Engine

FCoE (Fibre Channel over Ethernet) is a technology that allows Fibre Channel traffic to be encapsulated and transported over Ethernet networks. FCoE requires the use of FCFs (Fibre Channel Forwarders), which are devices that act as bridges between the FCoE and Fibre Channel domains. FCFs can be configured with a priority value that determines their preference for connecting to CNAs (Converged Network Adapters), which are devices that support both Ethernet and Fibre Channel protocols. The priority value ranges from 0 to 1024, with 0 being the lowest and 1024 being the highest. To configure an MDS switch as the best switch to connect by the CNAs in the fabric, the fcoe fcf-priority 1024 command should be applied. This gives the switch the highest priority and makes it the most preferred FCF for the CNAs.

References := Configuring FCoE

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5000/sw/fcoe/521n11/b_5k_FCoE_Config_521N11/ b_5k_FCoE_Config_521N11_chapter_011.pdf

 Option D and C are the correct policies that must be configured to meet the requirements. A Maintenance Policy specifies how the changes are applied when a service profile is associated or disassociated with a server or when an updated service profile is applied to a server. A Power Control Policy allows users to select how Cisco UCS Manager should restore power to the servers in a chassis after the chassis loses power. References:

• Cisco UCS Manager GUI Configuration Guide, Release 4.0 - Configuring Maintenance Policies [Cisco UCS Manager], Configuring Maintenance Policies, Configuring Maintenance Policies
• Cisco UCS Manager GUI Configuration Guide, Release 4.0 - Configuring Power Control Policies [Cisco UCS Manager], Configuring Power Control Policies, Configuring Power Control Policies

 Option D is the correct statement about the Deployment Immediacy for VMM domains associated to EPGs when the APIC EPG Resolution Immediacy is set to “Immediate”. This means that the policy is pushed to the hardware as soon as the leaf switch is booted, regardless of whether there are any VMs in the EPG or not. This ensures that the policy is ready to be enforced as soon as a VM is created or moved into the EPG. References:

• Cisco APIC Basic Configuration Guide, Release 4.2(x) - Configuring VMM Domains [Cisco Application Policy Infrastructure Controller (APIC)], Configuring VMM Domains, Configuring the Deployment Immediacy for VMM Domains
• Cisco APIC Basic Configuration Guide, Release 4.2(x) - Configuring VMM Domains [Cisco Application Policy Infrastructure Controller (APIC)], Configuring VMM Domains, Configuring the Resolution Immediacy for EPGs

 When a VLAN is added to a trunk and it does not appear on the vNIC of an associated server, it typically indicates that the vNIC template is not updating as it should to reflect changes. By changing the template type of Trunk-A to an updating template, any changes made to the trunk configuration, such as adding a new VLAN, will be dynamically applied to all vNICs associated with that template. This action will allow the newly added VLAN to be included in the vNIC configuration without the need to manually update each vNIC or recreate the templates.

References := This recommendation aligns with best practices for managing vNIC templates in Cisco UCS environments, where updating templates are used to ensure changes propagate automatically to all associated instances

The command checkpoint file before_maintenance is used to create a checkpoint of the current running configuration with the specified file name. The command rollback running-config file before_maintenance atomic ensures that the rollback of the checkpoint to the running configuration only occurs if there are no errors during the process. This is essential for maintaining the stability of the switch during maintenance operations.

Ansible is known for its agentless architecture, which means it does not require any software to be installed on the target devices. It can manage the devices using SSH, which is typically available on most Linux servers. This makes it suitable for scenarios where the operations team needs to update configurations across a large number of devices without direct access1.

References := For more information on how Ansible works and its capabilities for network automation, you can refer to the official Ansible documentation and resources available on the Ansible website1. These resources provide detailed guidance on using Ansible for network automation tasks, including configuration updates and management.