hard20 pts · first answer countsauthenticationnetworkingconcurrency

Parallel token refresh logs users out

When the access token expires, five parallel requests get 401 and each one starts a token refresh. The server rotates refresh tokens, so four refreshes fail and the user is logged out. What is the fix?

A.Turn off refresh token rotation on the serverB.Retry every 401 response five timesC.Make refresh single-flight: the first 401 starts one refresh behind a lock or shared task, the other requests wait for it and retry with the new tokenD.Store the refresh token in plain preferences so each request reads the newest value faster, which removes the race without changing the request flow

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