# USB2 or FireWire?

## bd

I am about to buy an external harddrive. Which interface would be the best choise considering Linux compability and speed?

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## hds

 *bd wrote:*   

> I am about to buy an external harddrive. Which interface would be the best choise considering Linux compability and speed?

 

well, friend of mine recently bought just a case. you put a normal IDE drive in, and the case has connections for USB and FireWire. maybe you should go for that?

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## AnimalMachine

Well I should have asked myself this question before getting a USB 2.0 drive encasing to build my own external drive ($152US total for a 200GB Seagate USB 2.0 external setup   :Wink:  ) ... but here's a site with some data:

http://www.usb-ware.com/firewire-vs-usb.htm

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## dtor

USB is for mice, Firewire is for men!   :Laughing: 

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## hds

 *dtor wrote:*   

> USB is for mice, Firewire is for men!  

 

5MBit should be enough for anyone   :Razz: 

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## fugitif

It seems that Firewire consumes less CPU. It could be a good point especially for people like me running CPU intensive tasks while burning on my firewire DVD  :Wink: 

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## dtor

 *hds wrote:*   

>  *dtor wrote:*   USB is for mice, Firewire is for men!   
> 
> 5MBit should be enough for anyone  

 

The famous last words   :Mr. Green: 

I prefer 800Mbits (1394b) + abilityto have multiple devices on the same wire though.

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## hds

nice! just wondering.. is 1394b using the same connectors then 1394?

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## dtor

It is said that 1394b controller can have a 'bilingual' connector allowing 1394a devices to connect to it but otherwise it's ether a or b wire.

More here:

http://www.1394ta.org/Technology/About/1394b.htm

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## bd

I'm going to buy a LaCie P3 250GB, either with USB2 or the $40 more expensive with FireWire.

Is the FireWire inteface so much better so that it's worth paying this additional cost. I'm going to use the drive to store movies, cd-images, music e.t.c. Prehaps I'll use it for the reason mentioned below too. 

Is it possible to have my whole Linux system on the external drive? I wonder because I would like to have the possibility to move the system between two computers. Which interface would be the best in this case?

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## hds

 *bd wrote:*   

> I'm going to buy a LaCie P3 250GB, either with USB2 or the $40 more expensive with FireWire.
> 
> 

 

why dont you take both in one? i mean, once you have such a drive, you might want to bring it to a friend because you want to share something. now it might happen that some of your friends might have USB only, or maybe just USB 1.0 but also firewire (faster). i wouldnt save on this few extra bucks..

 *bd wrote:*   

> 
> 
> Is the FireWire inteface so much better so that it's worth paying this additional cost. I'm going to use the drive to store movies, cd-images, music e.t.c. Prehaps I'll use it for the reason mentioned below too. 
> 
> 

 

well, once you might get a DV CAM and then you'll need firewire anyway. also the new firewire is much faster then USB 2.0.

 *bd wrote:*   

> 
> 
> Is it possible to have my whole Linux system on the external drive? I wonder because I would like to have the possibility to move the system between two computers. Which interface would be the best in this case?

 

this depends on the BIOS of the machine in question. have a look at the bootoptions, if you can selevt USB and/or firewire as 1st bootdevice. i guess most of the new machines support booting from USB - never seen a machine booting from firewire, but others mileage may vary.

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## bd

I don't need to boot from the HD, can have a CD-RW or likely for that. But does the kernel support it?

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## hds

 *bd wrote:*   

> I don't need to boot from the HD, can have a CD-RW or likely for that. But does the kernel support it?

 

havent tried it myself, but kernel 2.6.x should support both, usb and firewire. if you are running 2.6.x, have a look at your config:

CONFIG_IEEE1394_SBP2=m # firewire hd support

CONFIG_USB_DEVICEFS=y # usb devices

CONFIG_USB_STORAGE=y

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## tapted

Has anyone actually *used* a firewire external HD in linux???

Last I heard, firewire support wasn't all that crash-hot.

USB2.0 is faster than firewire, anyhoo, and any CPU usage pales in comparison to HD latency.

I've been using a USB2.0 external HD in my Gentoo-ed laptop for a week or so and had only minor problems (mainly coz they decided to remove supermount from kernel 2.6.8 .. grrrrrrrrr). The speed is fantastic (faster than my laptop hard drive, mostly). 25MB/sec is sustainable (my desktop drive gets about 42MB/sec and my laptop about 23MB/sec, so no complaints there).

Biggest decision was what filesystem to put on it... I now have it running with reiser4 and it's fan-bloody-tastic!

Moo.

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## dtor

 *tapted wrote:*   

> Has anyone actually *used* a firewire external HD in linux???
> 
> Last I heard, firewire support wasn't all that crash-hot.

 

Yes, I am using it (the HD) + DVD-RW chained to it, it works fine with my enclosure (2 x Bytecc-320u2f). Its a USB2+Firewire combos.

Both USB and firewire had (still have?) some glitches, but it works for me. The reason I am using firewire is because my laptop has only USB1.1 ports.

 *tapted wrote:*   

> 
> 
> USB2.0 is faster than firewire, anyhoo, and any CPU usage pales in comparison to HD latency.

 

USB2 raw speed (including protocol overhead) is 480Mbps

1394a is 400Mbps but overhead is less as far as I understand

1394b is 800Mbps typically but more expensive.

So you are just fine unless your drive delivers more than 50Mbp/s off the platters.

Anyway, inless you have something that requires firewire anyway I'd probably go with USB since it's $40 less for you. Are you sure its that more expensive? Here Firewire is only marginally more expensive, I think I bought my enclosure (the cheapest I could find so it's bulky and plastic) for $45 with both USB2.0 and Firewire...

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## dtor

 *hds wrote:*   

>  *bd wrote:*   I'm going to buy a LaCie P3 250GB, either with USB2 or the $40 more expensive with FireWire.
> 
>  
> 
> why dont you take both in one? i mean, once you have such a drive, you might want to bring it to a friend because you want to share something. now it might happen that some of your friends might have USB only, or maybe just USB 1.0 but also firewire (faster). i wouldnt save on this few extra bucks..
> ...

 

What you do not want to do is to use USB1.0 to access an external HD. So if your PC has only USB1 ports you are much better off with firewire. (I doubt that they even make external enclosures with USB1)

 *hds wrote:*   

>  *bd wrote:*   
> 
> Is the FireWire inteface so much better so that it's worth paying this additional cost. I'm going to use the drive to store movies, cd-images, music e.t.c. Prehaps I'll use it for the reason mentioned below too. 
> 
>  
> ...

 

I would not look at 1394b for now as they are more expensive and if external drive is used as just an extra storage USB2 and 1394a are both fast enough.

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## tapted

 *dtor wrote:*   

> 
> 
> What you do not want to do is to use USB1.0 to access an external HD. So if your PC has only USB1 ports you are much better off with firewire. (I doubt that they even make external enclosures with USB1)
> 
> 

 

Many USB2.0 devices are backwards compatible. My enclosure works fine with a USB1.0 mobo (and prolly 1.1 too)  -- it's just slow. 12Mbit/sec isn't all that bad though .. most of us put up with 10Mbit ethernet for yonks.

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