Layer-4 load balancer operating within a region, with zone redundancy on the Standard SKU; it has no WAF, doesn't terminate TLS and can't route by URL.
Also called LB, Standard Load Balancer.
Read more: Microsoft Learn
In the Ultra Transcenders books
AZ-305AZ-104AZ-700SC-500AZ-900
Each book explains Azure Load Balancer in context, with comparison tables and the common traps.
Terms in this definition
- ELT
Extract, load, transform: raw data lands in the target system first and is transformed there. See ETL for the opposite order.
- region
A provider-defined grouping in VCF Automation of Supervisors that all share one NSX Local Manager; tenants consume its compute, storage and memory via quotas set per region.
- Redundancy
So that hardware failures, datacentre outages or a regional disaster cannot destroy data, Azure Storage keeps multiple copies: only in the primary region with LRS and ZRS, or in a secondary region as well with GRS and GZRS.
- Standard deployment type
A Foundry deployment type billed per token that keeps processing of prompts and responses inside the Azure geography of the resource, meeting data residency needs at lower volumes.
- SKU
The size or tier of a service, for example a VM size or the Premium tier of ACR.
- Web Application Firewall
Protection at layer 7 from OWASP Top 10 threats like XSS and SQL injection, available on Application Gateway or Front Door.
- TLS
Transport Layer Security, the encryption protocol for traffic like HTTPS and Bastion sessions over port 443. On a storage account, minimumTlsVersion fixes the oldest accepted version without opening any network access.
- URL
The web address of a resource, on which URL-based routing relies.
Related terms
- 5-tuple
The five values that identify a flow: protocol plus the source and destination IP addresses and ports. Azure Load Balancer hashes them by default to spread traffic, and IP flow verify in Network Watcher takes them as its input.
- AllowAzureLoadBalancerInBound
Built-in NSG inbound rule at priority 65001 that admits traffic coming from Azure Load Balancer, health probes included.
- Azure Application Gateway
A load balancer for web traffic that works at layer 7, sending HTTP and HTTPS requests to back ends based on host name or URL path. It can also handle TLS termination and run a web application firewall, which Azure Load Balancer cannot since it doesn't read web requests.
- Backend pool
Targets of a load balancer, identified by IP address or NIC IP configuration. A pool can't span VNets, and a Standard load balancer won't accept a VM that has a Basic public IP.
- Basic SKU public IP
Public IP SKU, retired on 30 September 2025, that could be static or dynamic and was open by default; Standard Load Balancer, Bastion and Azure Firewall would not accept it.
- Cross-region load balancer
Global tier of Standard Load Balancer: a single anycast public IP fronts a backend pool made up of regional public Standard load balancers, and traffic goes to whichever healthy region is closest. Basic SKUs can't take part.
- Data Path Availability
Metric reporting frontend (VIP) availability on a Standard Load Balancer; check it first when a VM behind the load balancer appears to be down.
- Distributed network name
A SQL Server listener option on Azure VMs. Unlike a virtual network name (VNN) it works without any Azure Load Balancer and completes failover faster.