Informational

    HTTP 101 Switching Protocols

    The server is switching to a different protocol as requested by the client.

    Check a URL for HTTP 101

    Paste any URL to see whether it currently returns 101. Runs a live HTTP probe and follows redirects.

    What does HTTP 101 mean?

    HTTP 101 Switching Protocols indicates that the server understands and is willing to comply with the client's request to switch communication protocols. The most common use case is upgrading from HTTP to WebSocket.

    Common Causes

    • •WebSocket connection upgrade
    • •HTTP/2 upgrade from HTTP/1.1
    • •TLS upgrade via Upgrade header

    How to Fix It

    1. 1.This is expected behaviour for WebSocket connections
    2. 2.If WebSocket connections are failing, check your proxy/load balancer configuration

    SEO Impact

    No SEO impact. Protocol upgrades happen at the transport layer.

    Monitor HTTP 101 with LemWatch

    If your site uses WebSockets, LemWatch can monitor both the initial HTTP handshake and the WebSocket connection health.

    Related Status Codes

    100

    Continue

    200

    OK

    103

    Early Hints

    102

    Processing

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