I'm trying to run a LAMP webserver for an organization. I also need a testing server which presents no driver issues.
They have said that I can buy both. I want to be able to hot swap the drive while working or to copy while the server is up. I want to also be able to plug the drives directly out of the server and into the testing server with no driver issues.
The IT department says what I need is a 1U with hardware raid and a matching tower. Sounds a bit like overkill to me. The current server has to be replaced though because its slow.
Plugging drives out of the production server and plugging them in the development server implies that you need at least the same type of hardware. But even then, most RAID controllers store information like serial numbers or cached data of connected drives in their memory, and a disk swap may be well detected as a hardware failure and trigger a reprovisioning of that disk. In your situation temporarily mounting one disk into the directory of the other server over the network may be a saver way to solve your issue. It is also more flexible as you can work at different versions of your application in different directories at the same time, and switch from one to another version on your development or production server by just changing the mounting point.
this is how we did it for the BT Worldwide extranet back in the day.
we had. 1 Dev system 2 Test System (run as a technical copy) 3 Live
We had identical hardware for all 3 systems (3x 4u sun boxes) - the main networks/tech guy joked he wanted all the parts from the same production batch.
We would have liked a fourth machine as a hot spare in the exchange as to replace a hardware failure we would have had to fly the test machine up. And I suspect we might have had to threaten BA or Easy Jet with being black listed if they refused the server a ticket.
We could test then upgrade the live by swapping drives from test to live (after changing a few config lines to change the domain mostly)
Do you really need hot swap its going to be expensive and you do need a separate machine just for testing before going down hot swap raid arrays route.