Migrate server centos 7 on new hdd's

[dani50]

Hello everyone, I have a server with centos7 with 1TB raid (mirror) and I want to pass on the 2TB hdd. Which is the simplest solution to pass all the information on 2TB. Thanks in advance

[TrevorH]

How is the RAID set up? Is it a hardware RAID controller?

[dani50]

Yes,Is it a hardware RAID controller

[TrevorH]

Then look at its documentation. You can likely fail one of the existing drives, replace it with the new one, get it to re-build the array and then when that is completed successfully, you repeat it with the other drive. When both are replaced, then you look at expanding the array to occupy the entire new disks. Depending on the machine and its controller and what sort of backplane it has you may also be able to do all this without powering the machine off or rebooting until you get to the next step after expanding the array. If your drives are hot swappable then you should be ok to do all this online. Though backups never hurt...

[dani50]

Ok, thanks,
To me it is not the problem of degraded hdd, I want to change the hdd's because I got to 85% those of 1TB. I'll try this one. I hope it works

[tunk]

Beware that a rebuild can take a long time; you have to monitor
it on the card setup or to install some OS tools for your card.
It may be easier (and safer) to create a new raid, boot from a
live CD and use dd to make a raw disk copy. When that's done,
setup the card to boot from the second raid.

[TrevorH]

The whole point of having hardware RAID is so that you can do things like this. You can transparently replace failing/failed disks and have it rebuild them. You can replace working disks with others of the same or larger capacity. You can resize the array to take up that new space from the larger disks and you can do all that while your server is running.

[jlehtone]

Hardware raid controller is usually found in a server machine and servers tend to have space for more than two drives. One would then have chance to plug in all new drives before removing all of the old. Not that it would really matter on the necessary logical steps.

Time required for rebuild is often insignificant compared to cost of going offline.

[TrevorH]

Time required for rebuild is often insignificant compared to cost of going offline.

True. Also on all the h.w RAID controllers that I've used, they come out of the box configured to use no more than 30% of the available bandwidth while doing the rebuild, specifically to avoid impacting the rest of the work running on the server. Of course, if your server needs to use 100% of the available disk b/w then that would slow it down...

[dani50]

I'm sorry for the mistake, it's actually not hardware RAID controller, it's raid1 mirror on an Intel motherboard with i5 processor