Amazon Web Services will be updating a substantial number of its cloud servers, and has asked customers to re-launch their instances in the coming days, according to AWS consultants. Amazon has not said why the reboot is happening, but AWS watchers believe it is to patch a security issue. The company will be updating many of its servers between Thursday, Sept. 25 at 10 PM ET and Tuesday Sept. 30 at 7:59 PM ET, according to Amazon partner and cloud consultancy RightScale.