We've been happily running two Ubuntu 13.10 servers on Azure for the past month. Today, we updated one of them and rebooted - and now cannot ssh in to it at all. Rebooted 10 times, even did a full shutdown, still can't get in. So, we set up another machine to get back up and running, but after installing all the usual packages (node.js, mapnik), we restart the brand new machine and now that has stopped responding to ssh.
I just went to our main production machine and restarted - it's been very happy for a month, we've logged in every day without problem - and now that is unreachable. Node (started via Upstart) is running (I can do http requests and get responses perfectly fine), but I can't ssh in to the box.
I've searched around and all I can find online that shows a similar issue just suggests restarting the servers repeatedly, or worse, deleting the VMs and manually digging around to try to determine the root cause.
This really doesn't give me hope - we have three machines all showing the same problem on the same day, when we've had no trouble for months of running linux VMs? Our older VMs (> 1 month but have had regular updates) are running without any problems.
Any suggestions or thoughts as to why three have failed in one day? And how can we get them back?