Re: Migrating from hard drives to SSDs
On 7/11/23 21:39, David Christensen wrote:
On 7/11/23 13:18, Mick Ab wrote:
I am thinking of changing my storage from two 1TB hard drives in a
software
RAID 1 configuration to two M.2 Nvme 1 TB SSDs. The two SSDs would be put
into a software RAID 1 configuration. Currently each hard drive contains
both the operating system and user data.
What steps would you recommend to achieve the above result and would
those
steps be the quickest way ?
One of the M.2 slots can operate at PCIe 4.0 and PCIe 3.0, while the
other
slot can only operate at PCIe 3.0. If they are to be in a RAID 1 array, I
guess that both slots should be operated at PCIe 3.0 speed.
I would backup the system configuration files and data, power down,
remove the HDD's, install the NVMe drives, boot Debian installation
media, do a fresh install, restore/ merge the system configuration
files, and restore the data.
The above should be the most reliable approach and produce a "known
good" Debian system instance.
AIUI Linux md RAID can deal with block device speed differences.
Taking a step back, you might want to re-think using two 1 TB devices in
RAID1 for everything -- boot, swap, root, and data. I put boot, swap,
and root on a single 2.5" SATA SSD's and keep the entire instance small
enough to fit onto a "16 GB" device (you might want to target "32 GB",
"64 GB", etc., if you install a lot of software). I then put 2.5" SATA
trayless bays in all of my computers. This makes it easy to move OS
instances to other machines (subject to BIOS/UEFI compatibility), to
clone images to additional devices (USB flash drives, HDD's, SD cards),
and to take and store images on a regular basis for disaster
preparedness/ recovery. I would then wipe the 1 TB HDD's and build a
ZFS pool using the HDD's as a mirror. A surplus of memory will help ZFS
performance. For further ZFS improvements, add small/ fast/ high
endurance NVMe devices as ZFS cache and/or log devices.
David
One of the things apparently missing in today's support for the arm64
boards such as the bananapi-m5, is the lack of support for the nvme
memory on some of these devices. I have quite a few of them, all booting
and running from 64G micro-sd's. Yet these all have, soldered to the
board, several gigs of nvme memory, more that enough to contain a full
desktop install with all the toys, but totally unused.
So my question is, when do we get support for using it? It is reported
to be several times faster than the u-sd's its running from now. u-sd's
touted to do 100mhz/second, but generally can only do less than 20
megs/second in actual practice. So what plans are in place to use this
memory on the arms, that we users can look fwd to?
Thank you.
.
Cheers, Gene Heskett.
--
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.
- Louis D. Brandeis
Genes Web page <http://geneslinuxbox.net:6309/>
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