How does hot swap work?

[Jeff Gaines]

I Googled "how does hot swap work" and got a variety of contradictory
answers!

I am unclear as to whether it is a function of the drive, the caddy or the
OS (or something else, or perhaps a combination).

What I would like to do is have a caddy built into the computer case that
I can slot an SSD in and to be able to press a switch/button whatever and
pull it out without corrupting it.

Is that possible or am I asking for the unobtainable?

[wasbit]

Post by Jeff Gaines
I Googled "how does hot swap work" and got a variety of contradictory
answers!
I am unclear as to whether it is a function of the drive, the caddy or
the OS (or something else, or perhaps a combination).
What I would like to do is have a caddy built into the computer case
that I can slot an SSD in and to be able to press a switch/button
whatever and pull it out without corrupting it.
Is that possible or am I asking for the unobtainable?

Try changing your search terms to 'hot swap caddy' or 'hot swap drive bay'.

[Jeff Gaines]

Post by wasbit

Post by Jeff Gaines
I Googled "how does hot swap work" and got a variety of contradictory
answers!
I am unclear as to whether it is a function of the drive, the caddy or
the OS (or something else, or perhaps a combination).
What I would like to do is have a caddy built into the computer case that
I can slot an SSD in and to be able to press a switch/button whatever and
pull it out without corrupting it.
Is that possible or am I asking for the unobtainable?

Try changing your search terms to 'hot swap caddy' or 'hot swap drive bay'.

Thanks, I am crap at Googling :-)

[Theo]

Post by Jeff Gaines
I Googled "how does hot swap work" and got a variety of contradictory
answers!
I am unclear as to whether it is a function of the drive, the caddy or the
OS (or something else, or perhaps a combination).
What I would like to do is have a caddy built into the computer case that
I can slot an SSD in and to be able to press a switch/button whatever and
pull it out without corrupting it.
Is that possible or am I asking for the unobtainable?

First you need to unmount the drive. That's up to your OS.

Then you need a drive bay that supports pulling the drive without causing
electrical complications. The SATA connector is designed for this, but it's
possible the mobo is not (although it'll probably still work).

Then you need a controller and an OS driver that is happy for drives to come
and go. I think most controllers will support that, but eg RAID cards have
fancier features here.

I don't think there is anything different from a drive perspective - hotswap
looks just like power loss like turning off at the wall. It should be OK as
long as there is no writing in progress. Some drives (eg enterprise SSDs
and probably HDDs) have Power Loss Protection that tidies things away
while the power is going down.

Some chassis have hotswap features where pushing the button tells the OS to
unmount (so you can just walk into the server room and pull drives) but
that's not necessary if you've told the OS to unmount ahead of time.


TL;DR: if you have a drive in a caddy, unmount it and pull it. It should be
fine. After all, they sell caddies for this purpose and it's what happens
to USB drives all the time.

Theo

[Jeff Gaines]

On 26/10/2024 in message <d+f****@news.chiark.greenend.org.uk> Theo wrote:

[snipped]

Post by Theo
TL;DR: if you have a drive in a caddy, unmount it and pull it. It should be
fine. After all, they sell caddies for this purpose and it's what happens
to USB drives all the time.

Many thanks, Theo, I did read!

It seems that unless I unmount the drive I may have a corruption problem.
I think I will go back to my external USB drive as my "grab it and run"
drive.

[Andy Burns]

Post by Theo
if you have a drive in a caddy, unmount it and pull it. It should be
fine. After all, they sell caddies for this purpose and it's what happens
to USB drives all the time.

Check System Event Log to see if you get "Surprise removal" event 157

Also in Device Manager, consider disabling write-cache under device policy