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If you add "rest.use.authToken=true" internal property, any user can perform superuser operation if authToken is passed in URL parameter. The authToken will be logged into logs/teamcity-rest.log log. You will still need to supply valid user credentials to use this approach.
Data Backup
Start backup: POST http://teamcity:8111/httpAuth/app/rest/server/backup?includeConfigs=true&includeDatabase=true&includeBuildLogs=true&fileName=<fileName> where <fileName> in the prefix of the file to save backup to
Get current backup status (idle/running): GET http://teamcity:8111/httpAuth/app/rest/server/backup
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