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Amazon Forced To Reboot EC2 To Patch Bug In Xen
Bismillah writes AWS is currently emailing EC2 customers that it will need to reboot their instances for maintenance over the next few days. The email doesn't explain why the reboots are being done, but it is most likely to patch for the embargoed XSA-108 bug in Xen. ZDNet takes this as a spur to remind everyone that the cloud is not magical. Also at The Register.
You are actually required to program your application to expect failed database calls.
Yes, of course you are. Only an idiot would expect 100% of db calls to be successful.
"we will be re-booting the cloud today,,,in order to protect your 3,2 petabytes of data, you should download it to local storage in case of a fail event. thanks for using cloud storage on computing. have a great day."
never bring a twinkie to a food fight.
Be sure to thank Microsoft for teaching you the value of robust error checking. Assume any other host you need to talk to was nuked from orbit five seconds ago. Write your code to bounce back from that to the degree possible.
At the very least, DB *connections* should be assumed to have evaporated since the last time you accessed them. Use some sort of pooling library that can deal with that transparently if you like, or just catch & retry if necessary.
Seriously though, sounds like the environments you’ve worked in have been simple enough with low enough transaction volume that you got lucky & everything just worked. DB & app server on the same box maybe? Dealing with temporarily unavailable external hosts is just part of writing multi-tier code.
if you're in an transaction and it fails, you can just redo it. Thats the whole damn point.