On Friday Amazon Web Services issued an alert notifying customers of a reboot that could impact less than 10% of its servers because of a Xen vulnerability.
Yesterday, that news got better: AWS announced that less than 0.1% of Elastic Compute Cloud Servers would need to be rebooted to install a patch. For a company of AWS’s scale though, that will still be a lot of users.
+MORE AT NETWORK WORLD: What happens inside AWS when a Xen vulnerability is detected +
The reboot is needed because AWS uses the open source Xen hypervisor across its entire fleet of virtual machines and a security vulnerability has been discovered in the code.
Users may remember this isn’t the first time AWS has had to reboot it servers because of a Xen vulnerability. Last summer AWS rebooted about 10% of its servers for another Xen vulnerability.
AWS says this time, 99.9% of its servers can be patched while still running, so they doesn't require a reboot.