API Servers

The XConnect API runs on 7 dedicated physical servers, each hosting 43 isolated IIS application pools.

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Architecture Diagram

graph TB
    subgraph HAPROXY["Load Balancer"]
        LB["HAProxy VIP<br/>89.149.192.33"]
    end

    subgraph API_FARM["API Server Farm (7 Physical Dedicated Servers)"]
        subgraph API1["API-1: 10.32.8.134"]
            POOLS1["43 IIS Pools<br/>Ports 19169-19211"]
        end
        subgraph API2["API-2: 10.32.8.135"]
            POOLS2["43 IIS Pools<br/>Ports 19169-19211"]
        end
        subgraph API3["API-3: 10.32.8.139"]
            POOLS3["43 IIS Pools<br/>Ports 19169-19211"]
        end
        subgraph API4["API-4: 10.32.8.137"]
            POOLS4["43 IIS Pools<br/>Ports 19169-19211"]
        end
        subgraph API5["API-5: 10.32.8.35"]
            POOLS5["43 IIS Pools<br/>Ports 19169-19211"]
        end
        subgraph API6["API-6: 10.32.8.166"]
            POOLS6["43 IIS Pools<br/>Ports 19169-19211"]
        end
        subgraph API7["API-7: 10.32.8.167"]
            POOLS7["43 IIS Pools<br/>Ports 19169-19211"]
        end
    end

    subgraph DEPENDENCIES["Backend Dependencies"]
        SQL["SQL Server<br/>MainDB + Replicas"]
        MONGO["MongoDB<br/>Search Keys + Logs"]
        REDIS["Redis Cluster<br/>SP Data Cache"]
        SUPPLIERS["56+ Suppliers<br/>via Proxies"]
    end

    LB --> API1 & API2 & API3 & API4 & API5 & API6 & API7
    API_FARM --> SQL & MONGO & REDIS & SUPPLIERS

    style API_FARM fill:#e3f2fd
    style SQL fill:#FFB6C1
    style MONGO fill:#90EE90
    style REDIS fill:#ff9999

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Server Inventory

Server	IP Address	Type	IIS Pools	Port Range
API-1	10.32.8.134	Physical Dedicated	43	19169-19211
API-2	10.32.8.135	Physical Dedicated	43	19169-19211
API-3	10.32.8.139	Physical Dedicated	43	19169-19211
API-4	10.32.8.137	Physical Dedicated	43	19169-19211
API-5	10.32.8.35	Physical Dedicated	43	19169-19211
API-6	10.32.8.166	Physical Dedicated	43	19169-19211
API-7	10.32.8.167	Physical Dedicated	43	19169-19211
Total	-	7 Servers	301 Pools	-

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Server Specifications

Specification	Value
OS	Windows Server 2019/2022
Web Server	IIS 10.0
Framework	.NET 9 / ASP.NET Core
Pools per Server	43 (one per client domain)
Total Pools	301 across all servers
Concurrency	Async/Await pattern
Connection Pooling	SQL + HTTP connection reuse

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API Endpoints

Endpoint	Purpose	Volume
availability	Hotel search across suppliers	~7.3M/day
ReCheck	Price/availability verification	High
CancellationPolicy	Get cancellation terms	Medium
PreBook	Reserve before payment	Medium
Book	Confirm booking	~2,746/day
BookingDetail	Retrieve booking info	Medium
CancelBooking	Cancel reservations	Low

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Traffic Volume

Metric	Value
Daily Searches	~7.3 Million
Daily Bookings	~2,746
Avg RPS	2,300
Peak RPS	2,500
Off-hours RPS	2,200

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Deployment Process

Stage	Current	Future
Build	Visual Studio manual build	Jenkins automated build
Deploy	Manual copy to each server	GitLab CI/CD pipeline
Rollback	Manual restore	Automated rollback
Testing	Manual verification	Automated test suite

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Dependencies

graph LR
    API["API Servers"] --> SQL["SQL Server<br/>Writes: MainDB<br/>Reads: Replicas"]
    API --> MONGO["MongoDB<br/>Search Keys<br/>Logs"]
    API --> REDIS["Redis Cluster<br/>SP Cache"]
    API --> PROXY["Supplier Proxies"]
    PROXY --> SUPPLIERS["56+ Suppliers"]

    style API fill:#87CEEB
    style SQL fill:#FFB6C1
    style MONGO fill:#90EE90
    style REDIS fill:#ff9999

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Last Updated: 2025-12-02