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By default, MettleCI uses ports 8080 / 8443 (for the end-user UI) and 8081 (for the low-level diagnostics UI). There are two port-related scenarios that can cause Workbench to be unavailable:
The port for the UI you are trying to access is blocked by network-level or operating-system-level firewall rules. Time to talk to your friendly network administrator.
Either port is taken by other processes (e.g. a popular virus scanning application on Microsoft Windows often uses port 8081).
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Workbench may appear to start but the browser will fail to get a response when you go to
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You will need to change the conflicting port in Workbench's config.yml file in the MettleCI home directory.
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to its URL.
In either case you can resolve the problem by configuring MettleCI Workbench to use a custom port number.
Find out which ports are already in use
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