--- name: azure-expressroute description: Expert knowledge for Azure ExpressRoute development including troubleshooting, best practices, decision making, architecture & design patterns, limits & quotas, security, configuration, integrations & coding patterns, and deployment. Use when designing ExpressRoute circuits/gateways, BGP routing, Global Reach, FastPath, or S2S VPN coexistence, and other Azure ExpressRoute related development tasks. Not for Azure Internet Peering (use azure-internet-peering), Azure Peering Service (use azure-peering-service), Azure Virtual WAN (use azure-virtual-wan), Azure VPN Gateway (use azure-vpn-gateway). compatibility: Requires network access. Uses mcp_microsoftdocs:microsoft_docs_fetch or fetch_webpage to retrieve documentation. metadata: generated_at: "2026-04-12" generator: "docs2skills/1.0.0" --- # Azure ExpressRoute Skill This skill provides expert guidance for Azure ExpressRoute. Covers troubleshooting, best practices, decision making, architecture & design patterns, limits & quotas, security, configuration, integrations & coding patterns, and deployment. It combines local quick-reference content with remote documentation fetching capabilities. ## How to Use This Skill > **IMPORTANT for Agent**: Use the **Category Index** below to locate relevant sections. For categories with line ranges (e.g., `L35-L120`), use `read_file` with the specified lines. For categories with file links (e.g., `[security.md](security.md)`), use `read_file` on the linked reference file > **IMPORTANT for Agent**: If `metadata.generated_at` is more than 3 months old, suggest the user pull the latest version from the repository. If `mcp_microsoftdocs` tools are not available, suggest the user install it: [Installation Guide](https://github.com/MicrosoftDocs/mcp/blob/main/README.md) This skill requires **network access** to fetch documentation content: - **Preferred**: Use `mcp_microsoftdocs:microsoft_docs_fetch` with query string `from=learn-agent-skill`. Returns Markdown. - **Fallback**: Use `fetch_webpage` with query string `from=learn-agent-skill&accept=text/markdown`. Returns Markdown. ## Category Index | Category | Lines | Description | |----------|-------|-------------| | Troubleshooting | L37-L43 | Troubleshooting ExpressRoute resiliency and asymmetric routing issues, plus FAQs on connectivity models, supported services, bandwidth, and pricing to resolve design or outage-related questions. | | Best Practices | L44-L51 | Best practices for ExpressRoute: upgrading circuit bandwidth, using BGP communities in complex topologies, QoS for Skype voice, and migrating to new gateway hardware. | | Decision Making | L52-L61 | Guidance on choosing ExpressRoute connectivity models, VNets/gateways/SKUs, mapping providers to peering locations, and planning/migrating while managing ExpressRoute costs | | Architecture & Design Patterns | L62-L72 | Designing resilient, highly available ExpressRoute topologies, multi-circuit routing, coexistence with S2S VPN, DR/backup patterns, and using Microsoft peering for PSTN services. | | Limits & Quotas | L73-L80 | ExpressRoute bandwidth, route, and gateway limits, FastPath constraints, rate limiting on provider circuits, and how to monitor advertised routes to stay within quotas | | Security | L81-L90 | Encryption (IPsec, MACsec), NAT rules, RBAC roles, and security best practices for protecting ExpressRoute circuits and traffic | | Configuration | L91-L127 | How to configure and manage ExpressRoute circuits, peerings, VNets, gateways, routing/BGP, NAT, IPv6, monitoring, resiliency, and Global Reach using portal, PowerShell, and CLI | | Integrations & Coding Patterns | L128-L134 | Automating ExpressRoute circuit creation/management with PowerShell or Azure CLI, and configuring a site-to-site VPN that runs over ExpressRoute Microsoft peering. | | Deployment | L135-L141 | Guides for deploying and migrating ExpressRoute circuits/gateways, understanding Direct SKUs, testing multi-site resiliency, and automating setup with ARM templates, PowerShell, and Terraform. | ### Troubleshooting | Topic | URL | |-------|-----| | Test and validate resiliency of redundant ExpressRoute circuits | https://learn.microsoft.com/en-us/azure/expressroute/evaluate-circuit-resiliency | | Diagnose and resolve asymmetric routing with ExpressRoute | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-asymmetric-routing | | Azure ExpressRoute FAQ for services, costs, and connectivity | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-faqs | ### Best Practices | Topic | URL | |-------|-----| | Apply best practices for upgrading ExpressRoute circuit bandwidth | https://learn.microsoft.com/en-us/azure/expressroute/about-upgrade-circuit-bandwidth | | Manage complex ExpressRoute networks using BGP communities | https://learn.microsoft.com/en-us/azure/expressroute/bgp-communities | | Apply QoS requirements for Skype voice over ExpressRoute | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-qos | | Migrate legacy ExpressRoute gateway connections to new hardware | https://learn.microsoft.com/en-us/azure/expressroute/howto-recreate-connections | ### Decision Making | Topic | URL | |-------|-----| | Select and plan ExpressRoute virtual network gateways | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-about-virtual-network-gateways | | Choose the right Azure ExpressRoute connectivity model | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-connectivity-models | | Map ExpressRoute connectivity providers to peering locations | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-locations | | Plan and execute ExpressRoute gateway SKU migration | https://learn.microsoft.com/en-us/azure/expressroute/gateway-migration | | Plan and manage Azure ExpressRoute costs | https://learn.microsoft.com/en-us/azure/expressroute/plan-manage-cost | | Choose VNet connectivity options over ExpressRoute | https://learn.microsoft.com/en-us/azure/expressroute/virtual-network-connectivity-guidance | ### Architecture & Design Patterns | Topic | URL | |-------|-----| | Design resilient Azure ExpressRoute network architectures | https://learn.microsoft.com/en-us/azure/expressroute/design-architecture-for-resiliency | | Design disaster recovery with ExpressRoute private peering | https://learn.microsoft.com/en-us/azure/expressroute/designing-for-disaster-recovery-with-expressroute-privatepeering | | Architect high availability for Azure ExpressRoute | https://learn.microsoft.com/en-us/azure/expressroute/designing-for-high-availability-with-expressroute | | Optimize routing across multiple ExpressRoute circuits | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-optimize-routing | | Architect coexisting ExpressRoute and S2S VPN connections | https://learn.microsoft.com/en-us/azure/expressroute/how-to-configure-coexisting-gateway-portal | | Design S2S VPN backup for ExpressRoute private peering | https://learn.microsoft.com/en-us/azure/expressroute/use-s2s-vpn-as-backup-for-expressroute-privatepeering | | Use ExpressRoute Microsoft peering for PSTN services | https://learn.microsoft.com/en-us/azure/expressroute/using-expressroute-for-microsoft-pstn | ### Limits & Quotas | Topic | URL | |-------|-----| | Evaluate ExpressRoute FastPath features and limits | https://learn.microsoft.com/en-us/azure/expressroute/about-fastpath | | Monitor ExpressRoute advertised routes to avoid limits | https://learn.microsoft.com/en-us/azure/expressroute/how-to-custom-route-alert | | Understand rate limiting on provider-based ExpressRoute circuits | https://learn.microsoft.com/en-us/azure/expressroute/provider-rate-limit | | ExpressRoute scalable gateway features and limits | https://learn.microsoft.com/en-us/azure/expressroute/scalable-gateway | ### Security | Topic | URL | |-------|-----| | Use encryption options with Azure ExpressRoute | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-about-encryption | | Configure IPsec transport mode over ExpressRoute for Windows | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-ipsec-transport-private-windows | | Configure MACsec security for Azure ExpressRoute | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-macsec | | Apply NAT requirements for Azure ExpressRoute circuits | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-nat | | Roles and permissions for ExpressRoute resources | https://learn.microsoft.com/en-us/azure/expressroute/roles-permissions | | Apply security best practices to Azure ExpressRoute | https://learn.microsoft.com/en-us/azure/expressroute/secure-expressroute | ### Configuration | Topic | URL | |-------|-----| | Establish private ExpressRoute peering to an Azure VNet | https://learn.microsoft.com/en-us/azure/expressroute/configure-expressroute-private-peering | | Configure customer-controlled maintenance windows for ExpressRoute gateways | https://learn.microsoft.com/en-us/azure/expressroute/customer-controlled-gateway-maintenance | | Configure BFD over Azure ExpressRoute peering | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-bfd | | Configure NAT on Cisco and Juniper for ExpressRoute | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-config-samples-nat | | Router interface and BGP configuration samples for ExpressRoute | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-config-samples-routing | | Create and manage ExpressRoute virtual network gateways | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-add-gateway-portal-resource-manager | | Manage ExpressRoute virtual network gateways with PowerShell | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-add-gateway-resource-manager | | Add IPv6 support to ExpressRoute private peering | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-add-ipv6 | | Configure coexisting ExpressRoute and S2S VPN connections (classic) | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-coexist-classic | | Configure coexisting ExpressRoute and S2S VPN gateways | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-coexist-resource-manager | | Link VNets to ExpressRoute circuits using PowerShell | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-linkvnet-arm | | Link Azure VNets to ExpressRoute circuits via CLI | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-linkvnet-cli | | Link virtual networks to ExpressRoute circuits | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-linkvnet-portal-resource-manager | | Link virtual networks to ExpressRoute circuits | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-linkvnet-portal-resource-manager | | Reset ExpressRoute circuit peerings with PowerShell | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-reset-peering | | Reset ExpressRoute circuit peerings in Azure portal | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-reset-peering-portal | | Configure ExpressRoute routing and peering with PowerShell | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-routing-arm | | Configure ExpressRoute circuit peering in Azure portal | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-routing-portal-resource-manager | | Configure a scalable ExpressRoute gateway in portal | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-scalable-portal | | Configure ExpressRoute Global Reach with PowerShell | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-set-global-reach | | Configure ExpressRoute Global Reach in Azure portal | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-set-global-reach-portal | | Configure routing requirements for Azure ExpressRoute circuits | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-routing | | Configure Connection Monitor for ExpressRoute connectivity | https://learn.microsoft.com/en-us/azure/expressroute/how-to-configure-connection-monitor | | Configure custom BGP communities for ExpressRoute private peering | https://learn.microsoft.com/en-us/azure/expressroute/how-to-configure-custom-bgp-communities | | Configure custom BGP community values for ExpressRoute | https://learn.microsoft.com/en-us/azure/expressroute/how-to-configure-custom-bgp-communities-portal | | Configure ExpressRoute Traffic Collector and Log Analytics | https://learn.microsoft.com/en-us/azure/expressroute/how-to-configure-traffic-collector | | Configure Azure ExpressRoute Direct resources | https://learn.microsoft.com/en-us/azure/expressroute/how-to-expressroute-direct-portal | | Configure route filters for ExpressRoute Microsoft peering | https://learn.microsoft.com/en-us/azure/expressroute/how-to-routefilter-portal | | Configure ExpressRoute peering using Azure CLI | https://learn.microsoft.com/en-us/azure/expressroute/howto-routing-cli | | Use Azure Monitor metrics and logs for ExpressRoute | https://learn.microsoft.com/en-us/azure/expressroute/monitor-expressroute-reference | | Configure rate limiting on ExpressRoute Direct circuits | https://learn.microsoft.com/en-us/azure/expressroute/rate-limit | | Use Resiliency Insights for ExpressRoute gateways | https://learn.microsoft.com/en-us/azure/expressroute/resiliency-insights | | Validate ExpressRoute gateway resiliency and failover | https://learn.microsoft.com/en-us/azure/expressroute/resiliency-validation | ### Integrations & Coding Patterns | Topic | URL | |-------|-----| | Programmatically manage ExpressRoute circuits using Azure CLI | https://learn.microsoft.com/en-us/azure/expressroute/howto-circuit-cli | | Create and manage ExpressRoute circuits using Azure CLI | https://learn.microsoft.com/en-us/azure/expressroute/howto-circuit-cli | | Configure S2S VPN over ExpressRoute Microsoft peering | https://learn.microsoft.com/en-us/azure/expressroute/site-to-site-vpn-over-microsoft-peering | ### Deployment | Topic | URL | |-------|-----| | Migrate production workloads to a new ExpressRoute circuit | https://learn.microsoft.com/en-us/azure/expressroute/circuit-migration | | Understand ExpressRoute Direct SKUs and technical requirements | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-erdirect-about | | Deploy an Azure ExpressRoute circuit via ARM template | https://learn.microsoft.com/en-us/azure/expressroute/expressroute-howto-circuit-resource-manager-template | | Provision ExpressRoute circuit and gateway using Terraform | https://learn.microsoft.com/en-us/azure/expressroute/quickstart-create-expressroute-vnet-terraform |