Azure Load Balancer Flashcards
What are the primary features of Azure Load Balancer?
Layer 4 (Transport Layer)
TCP and UDP load balancing,
High availability,
Autoscaling,
Health probes,
Outbound rules
What types of Azure Load Balancers are available?
Basic
Standard
Public and Internal.
What is the difference between Basic and Standard Load Balancer?
Standard supports zonal failover, higher scale, and SLA-backed availability. Basic is limited to regional failover and smaller scale.
What is the purpose of health probes in Azure Load Balancer?
To monitor the health of backend instances, ensuring traffic is routed only to healthy instances.
How does Azure Load Balancer ensure high availability?
Distributes traffic across healthy instances in multiple availability zones and fault domains.
What security features are integrated into Azure Load Balancer?
NSG (Network Security Groups) for traffic filtering, DDoS protection for Standard tier.
What use cases are suited for Azure Load Balancer?
Web applications
distributed microservices
on-premises to cloud load balancing
and cross-region traffic distribution.
What purchasing tiers are available for Azure Load Balancer?
Basic and Standard.
What integration options does Azure Load Balancer support?
Azure Virtual Network, NSGs, Azure Firewall, DDoS Protection, Azure Monitor.
How does Azure Load Balancer handle disaster recovery?
Zonal failover with Standard Load Balancer, and geo-redundancy with cross-region load balancing.
How does Azure Load Balancer work with Azure Entra ID and RBAC?
RBAC provides role-based access control for managing load balancers and associated resources.
How does Azure Load Balancer manage outbound connections?
Outbound rules define how outbound connectivity is handled, supporting dynamic and static IPs.
What is the architecture of a Standard Load Balancer?
Zonal redundancy, managed endpoints in a region, supports HA and scale-out.
What are outbound rules in Azure Load Balancer?
Rules that define how traffic from internal VMs gets routed to external networks.
What is the SLA for Standard Load Balancer?
99.99% availability when used with two or more availability zones.
What is a Load Balancing rule?
Defines how traffic is distributed across instances based on IP and port configurations.
What are the key differences between Public and Internal Load Balancers?
Public exposes services to the internet, Internal is used within a virtual network for private services.
How does Azure Load Balancer handle session persistence?
Session persistence (or sticky sessions) ensures that client requests are directed to the same backend instance.
What monitoring tools are available for Azure Load Balancer?
Azure Monitor, Log Analytics, diagnostic settings for metrics and logs.
What is a scenario where an Internal Load Balancer is preferred?
When distributing traffic within a private network, such as between VMs in a VNet.
How does Azure Load Balancer support scaling?
Automatic scaling based on traffic patterns and backend pool instance count.
What is cross-region load balancing?
Distributing traffic across multiple regions to improve availability and latency.
How does Azure Load Balancer integrate with Virtual Machines?
Distributes traffic to VMs in a backend pool based on defined load balancing rules.
How is load distribution performed in Azure Load Balancer?
Hash-based distribution algorithm using 5-tuple (source/destination IP, port, and protocol).
What are backend pools in Azure Load Balancer?
A collection of virtual machines or instances that traffic is routed to based on load balancing rules.
What is the benefit of using a Standard Load Balancer for zonal redundancy?
Ensures traffic distribution across multiple availability zones, increasing fault tolerance.
How does Azure Load Balancer handle multiple front-end IPs?
Supports multiple front-end IPs for services that require different public or private IPs.
What is a floating IP in Azure Load Balancer?
Allows multiple front-end configurations with the same public IP, used in multi-tiered applications.
What type of workloads is Basic Load Balancer best suited for?
Small-scale, non-critical workloads, such as dev/test environments.
How does Azure Load Balancer manage multi-tenant scenarios?
Supports multiple back-end pools and IP configurations to handle different tenant requirements.
What is the relationship between NSGs and Azure Load Balancer?
NSGs can be used to control inbound and outbound traffic on Load Balancer endpoints.
What is the maximum number of backend instances supported in a Standard Load Balancer?
Up to 1,000 backend instances per load balancer.
What type of protocols does Azure Load Balancer support?
TCP and UDP.
What are inbound NAT rules in Azure Load Balancer?
Rules that map specific inbound traffic to individual backend instances.
How is session persistence configured in Azure Load Balancer?
Configured through Load Balancing rules, which allow enabling of session persistence.
What is the benefit of cross-region load balancing?
Improved latency, global redundancy, and automatic failover across multiple regions.
How does Azure Load Balancer ensure traffic distribution based on backend health?
Uses health probes to check the health of backend instances and only routes traffic to healthy instances.
What are health probes?
Probes used to check the health of backend VMs or services, configured with specific protocols and ports.
How does Azure Load Balancer improve network resiliency?
Ensures balanced traffic distribution across healthy instances and uses zonal redundancy for fault tolerance.
What is a common use case for Azure Load Balancer?
Load balancing traffic across web applications or microservices for better availability and scalability.
How does Azure Load Balancer handle auto-scaling?
Automatically scales backend pool instances based on traffic and health probes.
What Azure services integrate with Azure Load Balancer?
Azure Virtual Machines, Virtual Machine Scale Sets, App Service Environments, and Azure Kubernetes Service.
What is the cost difference between Basic and Standard Load Balancers?
Basic is free for limited use, Standard has charges based on usage (rules, data processed, etc.).
What is the purpose of a frontend IP configuration?
Defines the public or private IP used by the Load Balancer for distributing traffic.