The trunk group command associates a VLAN with a specific group of trunk ports. In an MLAG configuration, this feature is used as a best practice to isolate the MLAG peer VLAN. By assigning both the peer-link Port-Channel and the peer VLAN to the same unique trunk group, the switch ensures that the critical MLAG control plane traffic traversing this VLAN is confined exclusively to the peer-link. This prevents the peer VLAN from being inadvertently forwarded ("leaking") onto other trunk ports in the system, which could cause network instability or loops.

A. It groups all the trunks together so that they can traverse the peer-link properly.

This is incorrect. The command associates a VLAN with a group of trunks; it does not group trunks together. Its purpose is traffic isolation, not enabling traversal.

B. It groups the MLAG interfaces together so that they can be reported on both peers.

This is incorrect. The command is applied to a VLAN, not MLAG interfaces (Port-Channels), and its function is unrelated to reporting mechanisms.

D. It ensures that the configured VLAN will be included on all trunks.

This is the opposite of the command's function. It restricts the VLAN to only the trunks assigned to the specific group, rather than ensuring its inclusion on all trunks.

1. Arista Networks EOS 4.27.1F Configuration Guide, Section 22.3.2: MLAG Configuration Example.

The guide states, "The trunk group command ensures that the peer VLAN is only allowed on the peer link and not on any other trunk ports." This directly supports the correct answer by defining the command's purpose as preventing the VLAN from leaking.

2. Arista Networks EOS 4.27.1F Configuration Guide, Section 17.5.2: VLAN Trunk Group Configuration.

This section explains the general mechanism: "VLAN trunk groups provide a mechanism for specifying the set of VLANs that a trunk port can carry... A VLAN associated with a trunk group is carried only by trunk ports that are members of the group." This confirms the restrictive and isolating nature of the command.

3. Arista Design and Best Practices Guide, Section: MLAG Best Practices.

This design guide consistently recommends using a dedicated trunk group for the MLAG peer-link and peer VLAN to ensure control plane traffic is isolated from data plane trunks, reinforcing the principle of preventing traffic leakage.

The VLAN designated for the MLAG peer link is a special-purpose, point-to-point control plane link used exclusively for communication between the two MLAG peer switches. This communication includes synchronizing MAC and ARP tables and exchanging MLAG control protocol messages. The MLAG protocol itself inherently manages the Layer 2 topology to prevent loops from the perspective of downstream devices. Enabling Spanning Tree Protocol (STP) on this dedicated VLAN is not only unnecessary but can be disruptive. If STP were to calculate a loop and block the peer link port, it would sever the control plane connection, leading to a "split-brain" scenario where both peers operate independently, causing network instability and traffic disruption. Therefore, the standard and required best practice is to disable STP on the MLAG peer link VLAN.

The option "False" is incorrect because enabling Spanning Tree on the peer link VLAN directly conflicts with the operational requirements of MLAG. The MLAG control plane relies on a stable, uninterrupted connection over the peer link. STP, by design, could block this link, which would break the MLAG domain and negate the benefits of high availability and redundancy that MLAG is designed to provide.

1. Arista Networks, EOS 4.31.1F Configuration Guide: In the "MLAG" chapter, under the section "Configuring the Peer Link," the guide explicitly states the configuration requirement. It notes, "On the VLAN dedicated to the peer link, spanning tree must be disabled." This is presented as a mandatory step in the configuration process.

Reference: Arista EOS 4.31.1F Configuration Guide, Chapter: "MLAG", Section: "Configuring the Peer Link".

2. Arista Networks, "MLAG Best Practices" Design Guide: This document outlines the recommended design and configuration for a stable MLAG deployment. In the section covering the peer link, it reinforces this rule.

Reference: Arista Design Guides, "MLAG Best Practices", Section: "Peer Link", Subsection: "Configuration". The guide states: "Create a dedicated VLAN for the peer link. This VLAN should not be trunked anywhere else in the network. Disable spanning tree on this VLAN."

3. Arista Networks, "MLAG - Basic Configuration" Article: In this foundational configuration example on the Arista Community Central portal, the steps clearly demonstrate the requirement.

Reference: Arista Community Central, "MLAG - Basic Configuration" (Arista Validated Design), Configuration Example for Peer A and Peer B. Step 3 of the peer link configuration shows the command no spanning-tree vlan being applied to the peer link VLAN.

The command show vxlan address-table is the specific Arista EOS command used to display the VXLAN address table. This table contains the mappings of MAC addresses learned through the VXLAN data plane to their corresponding remote VTEP (VXLAN Tunnel End Point) IP addresses. The output also includes the associated VLAN and VNI (VXLAN Network Identifier), providing a complete view of the Layer 2 reachability information across the VXLAN fabric.

B. show vxlan mac-address-table: This is not a valid Arista EOS command. The correct syntax uses address-table, not mac-address-table, in the VXLAN context.

C. show mac-address-table: This command displays the standard Layer 2 MAC address table. While it will show MACs learned via VXLAN, it lists their port as the logical Vxlan1 interface, not the specific remote VTEP IP address.

D. show vxlan summary: This is not a standard command. Related commands like show vxlan vni summary provide a high-level overview of VNI states, not the detailed MAC-to-VTEP mapping table.

1. Arista Networks EOS Central, VXLAN Routing: The documentation explicitly lists and provides sample output for the show vxlan address-table command, showing its function is to display the "MAC address table for VXLAN." The output clearly contains columns for MAC Address, VLAN, VNI, and Remote VTEP.

Source: Arista EOS Central > Design & Deployment Guides > VXLAN > VXLAN Routing > Verifying VXLAN Routing.

2. Arista Networks EOS 4.21.3F Manual, Section: VXLAN Command Reference: This manual details the show vxlan address-table command. It describes the command as displaying the "VXLAN address table," confirming its purpose is to show MAC addresses learned over VXLAN tunnels and their associated remote VTEPs.

Source: Arista EOS 4.21.3F Manual, Page 1013.

3. Arista Networks, VXLAN Configuration Guide: In the verification sections of various VXLAN configuration examples, show vxlan address-table is consistently used to verify data-plane MAC learning from remote VTEPs. In contrast, show mac-address-table is used to verify local MAC learning and to see that remote MACs are associated with the Vxlan1 interface.

Source: Arista VXLAN Configuration Guide, Section: "Verifying the VXLAN Configuration".

The fundamental purpose of SysDB (System Database) is to serve as the centralized, in-memory state repository for the Arista Extensible Operating System (EOS). In the EOS multi-process architecture, various software agents (e.g., for routing, spanning tree, interface management) operate independently. They publish their state to SysDB and subscribe to relevant state changes from other agents. This state-sharing model decouples the processes from each other, which is key to EOS's high availability and resilience, as individual agents can be restarted without impacting the overall system state or other processes.

B. While user credentials are part of the system state, SysDB's purpose is to store all system state, not just this specific data.

C. Information about discovered systems (e.g., via LLDP) is just one of many types of state stored in SysDB, not its fundamental purpose.

D. SysDB is a core, well-documented, and functional component of the EOS architecture, not a marketing term.

1. Arista Networks, "Arista EOS White Paper": "At the core of EOS is a unique multi-process state-sharing architecture that separates state information from the processes themselves. This is the System Database, or SysDB. All of the switch’s state, from the ASIC forwarding tables to the switch’s spanning tree status, is held in SysDB. Various processes, known as agents, are responsible for a specific function of the switch... These agents interact with SysDB to maintain their state." (Page 3, Section: "EOS Architecture").

2. Arista Networks, "EOS Architecture - EOS Central": "At the core of EOS is a unique multi-process state-sharing architecture that separates state information from the processes themselves. This is the System Database, or SysDB... Each process, or agent, is responsible for a specific function... Agents communicate with each other by publishing and subscribing to changes in SysDB." (Section: "Sysdb").

VXLAN encapsulation adds a series of headers to the original Layer 2 frame to transport it over a Layer 3 network. This added overhead is calculated by summing the sizes of the new headers required for transport across the underlay network. The standard overhead for an IPv4 underlay consists of an Outer Ethernet header (14 bytes), an Outer IP header (20 bytes), an Outer UDP header (8 bytes), and the VXLAN header itself (8 bytes). The total overhead is 14 + 20 + 8 + 8 = 50 bytes. This is a critical consideration for network design, especially regarding MTU settings.

A. 10 bytes: This value is too low and does not account for the multiple headers (L2, L3, L4, and VXLAN) required for encapsulation.

B. 30 bytes: This is an incorrect calculation and does not represent the sum of the standard VXLAN encapsulation headers.

D. 70 bytes: This value represents the overhead when using an IPv6 underlay (40-byte header) instead of IPv4 (14 + 40 + 8 + 8 = 70 bytes). While possible, 50 bytes is the standard for IPv4.

1. Arista Networks, EOS-4.28.0F Manual, "VXLAN Bridging" section, "VXLAN MTU" subsection.

"VXLAN adds 50 bytes of overhead to a packet (14 byte MAC header, 20 byte IPv4 header, 8 byte UDP header, and 8 byte VXLAN header)." This official documentation directly confirms the 50-byte calculation.

2. IETF RFC 7348, "Virtual eXtensible Local Area Network (VXLAN)," Section 5, "VXLAN Packet Format."

This document defines the 8-byte VXLAN header and specifies the encapsulation method: "VXLAN is a Layer 2 overlay scheme over a Layer 3 network. It uses MAC-in-UDP encapsulation..." This supports the inclusion of UDP and underlying IP headers in the overhead calculation.

The statement is false. The zerotouch cancel command in Arista EOS provides a persistent method for disabling Zero Touch Provisioning (ZTP) by creating a specific marker file. When this command is executed, it creates a file named zerotouch-cancelled in the /mnt/flash/ directory. The presence of this file is what the boot process checks for. If this file exists, the ZTP process is skipped on all subsequent reboots, even if a startup-config file is not present. Therefore, issuing the write memory command is not required to make the cancellation of ZTP persistent.

The "True" option is incorrect because the persistence of the ZTP cancellation is not tied to the running-config or startup-config. The zerotouch cancel command performs a direct and persistent file system operation on the switch's flash memory, which survives a reboot independently of any configuration-saving commands like write memory. While saving a valid configuration is the ultimate goal after canceling ZTP, it is not the mechanism that makes the cancellation itself persist.

1. Arista EOS Configuration Guide: In the section describing Zero Touch Provisioning, the guide explains the cancellation process. It states, "To permanently disable ZTP, enter the zerotouch cancel command from the CLI. This command creates the file /mnt/flash/zerotouch-cancelled and ZTP will be disabled on all subsequent reboots." This explicitly confirms that the command itself creates a persistent state via a file, not through a configuration change that needs to be saved.

Source: Arista Networks, EOS 4.27.1F Configuration Guide, Section: "Zero Touch Provisioning (ZTP)", Subsection: "Disabling ZTP".

The command show event-monitor arp is used on an Arista switch to display the historical log of changes to the Address Resolution Protocol (ARP) table. This output is then piped (|) to the grep utility. The grep 10.100.100.6 part of the command acts as a filter, processing the output from the first command and displaying only the lines that contain the IP address "10.100.100.6". Therefore, the command's function is to show all historical ARP table events (additions, deletions, modifications) specifically related to the IP address 10.100.100.6 on the local switch where the command is executed.

A. This is incorrect because the command is executed on the local switch and queries its own event buffer. It does not connect to or retrieve information from a remote switch.

B. This is incorrect as the command filters the event log for entries containing a specific IP address, not for a switch that has a matching ARP address as its own identifier.

D. This is incorrect because Arista's Extensible Operating System (EOS) is built on a Linux kernel, and its command-line interface fully supports standard Linux tools like grep and piping (|) for output filtering.

1. Arista Networks EOS Configuration Guide: In the "Standard CLI Features" section, it details the use of the pipe (|) character to redirect the output of a show command to filters like grep. This confirms that show ... | grep ... is a valid and standard command structure. (Reference: Arista EOS Configuration Guide, section on "CLI Command Basics").

2. Arista Networks EOS Configuration Guide: The "System Monitoring" chapter describes the event-monitor feature. It states, "The show event-monitor command displays the contents of the event monitor buffer." The arp keyword specifies the buffer for ARP events, which logs additions and deletions from the ARP table. (Reference: Arista EOS 4.28.0F Configuration Guide, Chapter 45: System Monitoring, "Event Monitor" section).

3. Arista Networks Command Reference: The show event-monitor command is documented as the primary method for viewing historical event data captured by the event-monitor service. The arp parameter specifically targets the ARP table history. (Reference: Arista Networks Command Reference for the relevant EOS version).

The enable secret command is used to configure a secure, encrypted password for accessing Privilege Exec mode on an Arista switch. This command stores the password as a salted MD5 hash in the running configuration, providing a higher level of security than the enable password command. When a user enters the enable command to escalate privileges, they are prompted for this password. If both enable secret and enable password are configured, the enable secret takes precedence.

A. boot password: This is not a standard command for securing Privilege Exec mode; it relates to the Aboot (bootloader) environment for tasks like password recovery.

C. management secret: This is not a valid Arista EOS command for configuring the Privilege Exec mode password.

D. enable: This is the command used to enter Privilege Exec mode from User Exec mode, not the command used to configure its password.

1. Arista Networks, "EOS System Security Configuration Guide," Release 4.28.0F, Section: "Passwords," Subsection: "Privileged EXEC Mode Password." The document states, "The enable secret command configures the password required to enter privileged EXEC mode... The enable secret command provides more security than the enable password command by storing the password as a salted MD5 hash."

2. Arista Networks, "EOS Configuration Guide," Release 4.21.3F, Section 6.2.1: "Passwords." This section details the use of enable secret to set the password for privileged mode access, explaining its encryption and precedence.

VTEP stands for VXLAN Tunnel Endpoint. It is a functional entity or device that originates and terminates VXLAN tunnels. The VTEP is responsible for the critical functions of encapsulating Layer 2 Ethernet frames from a source virtual network into VXLAN/UDP/IP packets for transport across the underlying Layer 3 network, and decapsulating them at the destination to deliver the original Ethernet frame. This process allows for the extension of Layer 2 segments over a Layer 3 infrastructure, a core capability of VXLAN technology.

B. VNI: VNI stands for VXLAN Network Identifier. It is a 24-bit field in the VXLAN header used to identify a specific virtual network segment, analogous to a VLAN ID, not a device.

C. VXLAN: VXLAN (Virtual Extensible LAN) is the name of the network virtualization protocol itself, which specifies the encapsulation format and behavior, not the device performing the function.

D. VTP: VTP (VLAN Trunking Protocol) is a Cisco-proprietary messaging protocol used to manage the addition, deletion, and renaming of VLANs on a network-wide basis; it is unrelated to VXLAN.

1. IETF RFC 7348, "Virtual eXtensible Local Area Network (VXLAN): A Framework for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks":

Section 4.1, "VTEP": "VXLAN Tunnel Endpoint (VTEP). This is the entity that originates and/or terminates VXLAN tunnels." This section explicitly defines the VTEP as the device performing the encapsulation and decapsulation.

Section 5, "VXLAN Header": "VXLAN Network Identifier (VNI): 24 bits. This is an identifier for the virtual network segment." This defines the VNI as a segment identifier, not a device.

2. Arista Networks, "EOS 4.31.2F - 7050X3 Series Configuration Guide":

Chapter 41, "VXLAN", Section "VXLAN Overview": "A VTEP is a device that terminates a VXLAN tunnel, and maps tenant end devices to VXLAN segments. VTEPs perform VXLAN encapsulation and decapsulation." This official vendor documentation directly confirms the role of the VTEP.

The provided output is from the show monitor session MIRROR command. The key lines in the output are Truncate: enabled and Truncate size: 128 bytes. These lines explicitly indicate that the packet truncation feature is active for this port mirroring (SPAN) session. Packet truncation allows for copying only the initial portion of a packet to the destination, which is useful for analyzing headers while conserving bandwidth on the monitoring link and resources on the analysis tool.

B. Advanced Mirroring with ACLs: The output does not show an Access Control List (ACL) being used as a filter for the source traffic. If an ACL were applied, it would be listed in the session details.

C. Agile Ports: Agile Ports refer to the capability of a physical port to operate at different speeds or in breakout modes. This is a physical layer configuration and is not displayed in the show monitor session output.

D. Buffer Tuning: Buffer tuning involves adjusting memory allocation for ingress or egress queues to manage traffic bursts. This is a Quality of Service (QoS) feature, and its status is not shown by the port mirroring command.

1. Arista EOS Configuration Guide 4.27.1F: In the "Port Mirroring (SPAN)" section, under the subsection "Packet Truncation," it states, "Packet truncation enables the switch to forward a specified number of bytes from each packet to the destination port." The guide shows the show monitor session command output, which includes the "Truncate" and "Truncate size" fields, matching the question's image. (See Section 25.3.5 - Packet Truncation).

2. Arista EOS Configuration Guide 4.27.1F: The section on "Mirroring to an ACL" demonstrates that when an ACL is used, the show monitor session output would include a line specifying the ACL name, which is absent in the provided image. (See Section 25.3.4 - Mirroring to an ACL).