Hi.  So, I have a few omnios instances in AWS running on nitro instance types.   Today they all, at some point or other, rebooted with no prompting from me.  I cannot see any RebootInstances API calls in cloudtrail, so I am reasonably sure no one initiated a reboot from the AWS console or with awscli.  They all show log messages like "Jul 19

12:26:47 ip-xx-xx-xx-xx poweroff: [ID 330035 auth.crit] initiated by LOGIN on /dev/console"   All machines have the console on the serial port.   I remember from many moons ago sparc solaris boxes rebooting when the machine at the other end of the serial cable was rebooted.  Is this still a thing on omnios on x86?   If so, does it seem

possible that a similar reboot could be triggered in AWS?

That's the message from someone pressing the (virtual in this case) power button.

Which sounds like something associated with the AWS host underneath the instance.

Well, yes.  But that should be in response to a RebootInstances api call, that is what I see when I reboot from the console.  But there were none.

reboot from the AWS console

No, if the AWS host underneath reboots, there is no API call at the instance level.

Ok.  But all of them in one day?  It was a very odd event.  A number of them rebooted more than once.  No notifications from AWS.   I ran "svccfg -s svc:/system/keymap:default setprop keymap/keyboard_abort=disabled && kbd -i" on them all just in case the serial break was to blame.

That coincidence is more like an underlying infrastructure event - certainly when I was running lots of OmniOS on AWS the unexplained reboots tended to come in clusters.

One interesting thing to note is that none of the t2 instances rebooted during the event.

Another interesting thing to note is none of the linux t3 instances rebooted.

And there are many more of those.