Live migration web server
 

Hi,

we have big virtual server with webs (apache) on "slow" magnetic disks. We want to buy new SSDs and migrate data.

It seems me the best way is to connect SSD as disk to virtual and migrate data from slow disks to SSD.

My question is how to do that without fails. I can't turn off the server and dd the disks ...

Any ideas / own experience?

Thanks

What kind of disks and in what configuration?
What virtualization software?
What Linux distribution and version does it run?
Any particular CMS or other software or system services we should know about?
Why only a web server instead of a redundant platform with separate load balancers, web servers, database cluster, caching servers, shared storage etc, etc?


Say you do. What indicators will you use to tell if /when that doesn't provide enough performance?..


Depending on your virtualization platform you may be able to clone the machine?.. By the way, sure you need to rsync data afterwards to be sure and take care of databases but 'dd' doesn't require you to shut down disks...