udev or mdev?

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udev or mdev?

Pandu Poluan

Hello Server people!

With the recent brouhaha on udev vs mdev back in the -user list, I just wondered about whether any server guy/gal here (beside me) actually use mdev instead of udev for the servers?

So, an informal poll time!

a. I'm using udev and will still be using udev, latest version

b. I'm using udev and will still be using udev, but I'll mask 181 and later (the versions that require /usr to be present during boot)

c. I'm using udev but will transition to mdev

d. I'm using mdev already.

e. A write in vote (please explain)

I personally choose (d), because I like simpler systems (no initramfs), and I know *exactly* what's going on during boot if I go the mdev route.

What's your answers?

Rgds,

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Re: udev or mdev?

Kalin KOZHUHAROV
f. I didn't know mdev existed, will research and answer later :-|

Cheers,
Kalin.

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Re: udev or mdev?

Pandu Poluan


On Mar 19, 2012 8:33 AM, "Kalin KOZHUHAROV" <[hidden email]> wrote:
>
> f. I didn't know mdev existed, will research and answer later :-|
>
> Cheers,
> Kalin.
>

While researching, make sure to stop by this page:

http://www.waltdnes.org/mdev/

Rgds,

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Re: udev or mdev?

Halassy Zoltán
In reply to this post by Pandu Poluan
> a. I'm using udev and will still be using udev, latest version

This.

Question: Why would I replace a known system to a unknown one? The
effort required to replace udev with mdev could be used to create an
initramfs to mount that /usr , or alter the /etc/init.d/udev-mount to
depend on an extra service, which does nothing else, but mount /usr .
With the latter, further upgrades would just need to keep the extra
depend in the init script, long live config-protect.


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Re: udev or mdev?

Pandu Poluan


On Mar 19, 2012 5:39 PM, "Halassy Zoltán" <[hidden email]> wrote:
>>
>> a. I'm using udev and will still be using udev, latest version
>
>
> This.
>
> Question: Why would I replace a known system to a unknown one? The effort required to replace udev with mdev could be used to create an initramfs to mount that /usr , or alter the /etc/init.d/udev-mount to depend on an extra service, which does nothing else, but mount /usr . With the latter, further upgrades would just need to keep the extra depend in the init script, long live config-protect.
>

IMO, initramfs adds yet another black box during server boot. Plus, udev is getting more and more complex with all its intelligence. And yet another daemon in memory, something I certainly don't need on my static virtualized servers.

Rgds,

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Re: udev or mdev?

Halassy Zoltán
> IMO, initramfs adds yet another black box during server boot.

The other way around, for me at least. I build my own initramfs, yet I
don't know anything about mdev, just the fact it's part of busybox. So
for me, mdev is a black box, while my initramfs definitely isn't.

> And yet
> another daemon in memory, something I certainly don't need on my static
> virtualized servers.

I agree with that. But why do you need mdev for a static system? A few
mknods would suffice.


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Re: udev or mdev?

Pandu Poluan


On Mar 21, 2012 4:23 PM, "Halassy Zoltán" <[hidden email]> wrote:
>>
>> IMO, initramfs adds yet another black box during server boot.
>
>
> The other way around, for me at least. I build my own initramfs, yet I don't know anything about mdev, just the fact it's part of busybox. So for me, mdev is a black box, while my initramfs definitely isn't.
>
>

I see. Well, different views for different people, I guess.

It's easier for me to bypass mdev (if it's b0rken) than to bypass initramfs.

>> And yet
>> another daemon in memory, something I certainly don't need on my static
>> virtualized servers.
>
>
> I agree with that. But why do you need mdev for a static system? A few mknods would suffice.
>

It allows triggered action when I (for example) attach a (virtual) hard disk to my VM.

Rgds,

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Re: udev or mdev?

Bugzilla from dubkat@gmail.com
people actually need an initramfs?

my kernel has only what it needs, and nothing it doesn't.

On Wed, Mar 21, 2012 at 5:39 AM, Pandu Poluan <[hidden email]> wrote:

>
> On Mar 21, 2012 4:23 PM, "Halassy Zoltán" <[hidden email]> wrote:
>>>
>>> IMO, initramfs adds yet another black box during server boot.
>>
>>
>> The other way around, for me at least. I build my own initramfs, yet I
>> don't know anything about mdev, just the fact it's part of busybox. So for
>> me, mdev is a black box, while my initramfs definitely isn't.
>>
>>
>
> I see. Well, different views for different people, I guess.
>
> It's easier for me to bypass mdev (if it's b0rken) than to bypass initramfs.
>
>>> And yet
>>> another daemon in memory, something I certainly don't need on my static
>>> virtualized servers.
>>
>>
>> I agree with that. But why do you need mdev for a static system? A few
>> mknods would suffice.
>>
>
> It allows triggered action when I (for example) attach a (virtual) hard disk
> to my VM.
>
> Rgds,

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Re: udev or mdev?

Drew-12
On Wed, Mar 21, 2012 at 7:17 PM, Daniel Reidy <[hidden email]> wrote:
> people actually need an initramfs?
>
> my kernel has only what it needs, and nothing it doesn't.

+1

Only time I used initramfs was on a desktop and that was while testing
a quirky lvm/raid setup that wouldn't boot without mdadm doing some
assembly *before* the main root filesystem became available. That was
never production quality though and all my servers run either off a HW
RAID card or boot from a SAN.


--
Drew

"Nothing in life is to be feared. It is only to be understood."
--Marie Curie

"This started out as a hobby and spun horribly out of control."
-Unknown

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Re: udev or mdev?

brm-3
In reply to this post by Pandu Poluan
> From: Pandu Poluan <[hidden email]>

>On Mar 21, 2012 4:23 PM, "Halassy Zoltán" <[hidden email]> wrote:
>>> IMO, initramfs adds yet another black box during server boot.
>> The other way around, for me at least. I build my own initramfs, yet I don't know anything about mdev, just the fact it's part of busybox. So for me, mdev is a black box, while my initramfs definitely isn't.
>I see. Well, different views for different people, I guess.
>It's easier for me to bypass mdev (if it's b0rken) than to bypass initramfs.


As I've had to use BusyBox extensively in some environments, I find their tools very lacking in comparison to non-BusyBox environments.
As such, I've come to really hate mdev, and I'll keep udev around for as long as it is the "standard" or until that "standard" changes to something better - of which, mdev it will not be.

$0.02

Ben