Here is a tutorial that will come handy one day, in the moment of panic – How to Recover an Unreachable Linux Instance. It has plenty of screenshots and shows each step in detail.
TL;DR version:
- Start a new instance (or pick one from the existing ones).
 - Stop the broken instance.
 - Detach the volume from the broken instance.
 - Attach the volume to the new/existing instance as additional disk.
 - Troubleshoot and fix the problem.
 - Detach the volume from the new/existing instance.
 - Attach the volume to the broken instance.
 - Start the new instance.
 - Get rid of the useless new instance, if you didn’t reuse the existing one for the troubleshooting and fixing process.
 - ???
 - PROFIT!
 

RT @mamchenkov: How to Recover an Unreachable Linux Instance #Linux #AWS #EC2 #Amazon #SysAdmin #DevOps https://t.co/4NGLvOI9Mz
This can be done to rescue s Windows server, too. If, of course, you can reach storage system from Linux :-)
Windows is beyond rescue ;)
Cheap shot at Microsoft technologies. They are superior to everything else :-)
Yeah, they were. Until Microsoft themselves said they are not anymore. But I’m guessing you’ll get those news in a bit. Maybe next decade. :)
Nope, I am still in 24-bit address space of System/370, cannot jump past 4096 bytes without using USING :-)
Hahaha … yeah, nice … and then again I remember a server with a 1 TB of RAM and god knows how many CPUs – the picture that you posted a few weeks back :)
That was not mine, but company server, bought by our almighty sysadmin Misha. He is far more advanced in technology than I am.