Arista Foundations flashcards
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32 cards. Read the term and the definition here. The deck at the top of this page is optional.
- EOS CLI shell
- EOS runs on a Linux kernel; the CLI is a Bash shell, so standard Linux commands and tools such as grep, tcpdump, and ip are available directly on the switch.
- eAPI
- Arista's JSON-RPC API over HTTP/HTTPS that allows programmatic configuration and command execution on EOS devices, enabled with the 'management api http-commands' command.
- MLAG peer link
- A Layer 2 link between two MLAG switches that carries data traffic and synchronizes MAC and ARP tables; it is separate from the Layer 3 peer-keepalive link used for health checks.
- VXLAN VTEP
- A VXLAN Tunnel Endpoint that encapsulates Layer 2 frames into UDP packets for transport over a Layer 3 underlay; typically a loopback interface on a leaf switch.
- ZTP
- Zero Touch Provisioning: a switch boots without config and automatically fetches an image and configuration via DHCP options or a USB drive, enabling automated deployment.
- EOS rollback checkpoint
- A saved snapshot of the running configuration that can be restored with the 'rollback' command; checkpoints are stored in a repository and can be compared or replaced.
- Leaf-spine full mesh
- A topology where every leaf switch connects to every spine switch, and spines do not interconnect; any leaf-to-leaf path is at most two hops.
- ECMP hashing
- Equal-Cost Multi-Path load balancing distributes flows across multiple equal-cost next hops using a hash of the 5-tuple (source/destination IP, source/destination port, protocol).
- Oversubscription ratio
- The ratio of host-facing (southbound) bandwidth to uplink (northbound) bandwidth on a leaf switch; 1:1 is non-blocking, while 3:1 is common for general-purpose compute.
- vPC
- Arista's term for MLAG: two leaf switches act as a single logical device to dual-home servers, using a peer link and peer-keepalive for synchronization and health checking.
- BGP underlay ASN design
- In a leaf-spine underlay, each leaf typically uses a unique ASN while all spines share a common ASN (or use BGP unnumbered) to build loopback reachability with ECMP.
- Spine layer role
- The spine layer provides high-radix, high-bandwidth interconnection between leaves; spines do not connect to each other and forward traffic between leaf switches.
- CloudVision CVP vs CVaaS
- CVP is the on-premises CloudVision platform; CVaaS is the cloud-hosted SaaS version. Both provide change management, provisioning, telemetry, and compliance for EOS devices.
- TerminAttr agent
- An EOS on-device agent that streams telemetry and configuration state to CloudVision using gNMI/OpenConfig, enabling visibility and change tracking.
- Configlet
- A reusable configuration snippet in CloudVision that is attached to containers; changes generate tasks that can require approval before deployment to devices.
- CloudVision Studios
- Intent-based provisioning workflows in CloudVision (e.g., L3 Leaf-Spine studio) that generate configlets from a declarative model, reducing manual CLI configuration.
- Compliance dashboard
- A CloudVision feature that compares each device's running configuration against its designed configuration, flags drift, and can trigger automated remediation via change control.
- CloudVision RBAC
- Role-based access control in CloudVision that restricts user actions by role; it supports local users and integration with TACACS+ or RADIUS, with audit logging of changes.
- BGP best-path order
- Selection order: weight, local preference, locally originated, AS path length, origin, MED, eBGP over iBGP, IGP metric to next hop, router ID.
- EVPN route type 2
- A BGP EVPN route that advertises MAC and IP address bindings for hosts; it enables Layer 2 and Layer 3 forwarding in VXLAN overlay networks.
- BGP unnumbered
- A BGP configuration that uses IPv6 link-local next hops over point-to-point interfaces, eliminating the need for per-link IP addressing in the underlay.
- OSPF area 0
- The backbone area of an OSPF domain; all other areas must connect to area 0, and area border routers (ABRs) link non-backbone areas to the backbone.
- VRF
- Virtual Routing and Forwarding: a technology that creates separate routing tables on the same device, isolating traffic between tenants or networks without MPLS.
- Route redistribution
- The process of injecting routes from one routing protocol into another; it requires route-maps to control which routes are advertised and to prevent routing loops.
- sFlow
- A packet sampling technology that captures 1 in N packets and exports flow data to a collector, providing traffic visibility without full packet capture.
- ERSPAN
- Encapsulated Remote SPAN: mirrors traffic from a source port or VLAN and encapsulates it in GRE for transport to a remote collector over a routed network.
- MACsec
- A Layer 2 encryption standard that secures point-to-point Ethernet links; EOS supports MACsec on select platforms for inter-switch and host connections.
- CoPP
- Control-Plane Policing: rate-limits exception traffic (e.g., BGP, SSH, ARP) destined to the switch CPU, protecting the control plane from overload and DoS attacks.
- Arista DANZ
- Data Analyzer: a set of advanced monitoring features on supported Arista platforms that provides flow-based filtering, timestamping, and precise traffic analysis.
- TACACS+
- A AAA protocol that provides separate authentication, authorization, and accounting for device access; EOS supports TACACS+ with local fallback for recovery.
- gNMI telemetry
- A gRPC-based protocol using OpenConfig models to stream near-real-time state and counters from EOS devices to CloudVision or other collectors.
- Port mirroring (SPAN)
- A feature that copies traffic from a source port or VLAN to a destination port for analysis; local SPAN stays on the switch, while ERSPAN sends traffic remotely.