Talk:USB flash installation media

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Verifying the USB

Before and after having performed the dd onto the USB disk, check that the md5sums are correct. For example:

- $ md5sum archlinux-2008.06-core-x86_64.img && echo && cat md5sums.x86_64

The next command will give similar results, but will also let you confirm that the data was written correctly and can be read correctly:

- dd if=/dev/sdb count=661159 status=noxfer | md5sum && echo && cat md5sums.x86_64

--Zatricky 06:45, 22 January 2009 (EST)

dd for Windows

There is also dd for Windows. I tried it and it works perfectly: [1]

 dd if=file.img of=\\.\e:

where e: is your USB drive letter.

--Liquen 14:55, 4 April 2009 (EDT)

About making the installation media without overwriting

I'm not totally sure if I misunderstood something, but I had to change the path of the entries of the *.cfg files. For instance:

INCLUDE boot/syslinux/archiso_sys.cfg


INCLUDE syslinux/archiso_sys.cfg

It was the only way it worked with the unofficial ISO x86_64 image of march 13th, 2012. Looks like the syslinux command described in the page doesn't get the path as it should.

I edited all of the .cfg files, but probably only editing this ones should have been enough:

archiso.cfg archiso_head.cfg archiso_sys_inc.cfg

I hope it could be useful to somebody, because I spend some time with this (I even thought that was a problem with the hardware). I think it could be possible to make a simple script (or give some command lines) to patch the files once they are copied into the USB and run syslinux.

Thanks !!

Recovering the USB drive afterwards

This didn't work for me:

  1. dd count=1 bs=512 if=/dev/zero of=/dev/sdx

I tried this multiple times. No matter how I formatted the disk, 'devmon' always mounted '/dev/sdd' as /media/ARCH_whatever.

I finally just zeroed as much of the disk as I thought the ISO might have been written to.

  1. dd count=100 bs=4M if=/dev/zero of=/dev/sdx; sync

That worked. I believe we need to zero MORE than just the initial 512 bytes, but I have no idea how much. Maybe 2048?

At any rate, put '; sync' in there somewhere.

This is what I did eventually, taking a tip from: [2]

  1. dd count=100 bs=4M if=/dev/zero of=/dev/sdx; sync
  2. fdisk -H 224 -S 56 /dev/sdx

(new partition, primary, 1, 2048, whatever, type of partition, c (fat32 LBA), x, beginning data sector, 256, write)

  1. mkfs.vfat -F 32 -n volume_label -s 32 -v /dev/sdx1; sync

See the link for more details on the beginning data sector.

  • Um, zeroing out the first 512 bytes is fine for MBR-formatted drives. Were you using GPT? Because then you would need to zero out the first 512+512+16k, and the last 16k+512. See GPT. But assuming you used dd, we're talking about MBR-formatted because the ISO contains a MBR (hybrid) partition table.--DSpider (talk) 06:25, 8 September 2012 (UTC)

flush file system buffers after dd

I found that after using dd to write the data to my USB I had to wait for the file system to actually write it to my drive. (as dd completed and returned its stats) This could cause confusion, should we add 'sync' after the dd command on the artical?

Rationale for block size

Why specifically bs=4M in the example:

# dd bs=4M if=/path/to/archlinux.iso of=/dev/sdx

NoobCp (talk) 11:08, 20 December 2012 (UTC)

Because it speeds up the process, that's why. I guess somebody decided that one warning, two notes and a tip would be too rainbow-like. See this older edit (which references this script). I reduces the time it needs almost by half. --DSpider (talk) 12:17, 4 February 2013 (UTC)

UNetbootin should be removed

I think UNetbootin should be removed. It was just added more information that basically tells you to use something else. This program is way too intrusive. It installs its own version of the bootloader, a crappy syslinux.cfg, and doesn't give a shit about labels. Unetbootin is totally NOT recommended for Arch Linux and it should be removed from the wiki. --DSpider (talk) 11:20, 16 September 2012 (UTC)

Thanks. Good riddance! But, perhaps we should keep the warning? Or just refer them to this discussion page. --DSpider (talk) 06:01, 17 September 2012 (UTC)
This is not the first time UNetbootin info is added and then removed (sadly by me.). Search the history you will find the same topic show up long time ago. If it is broken, we'd better clearly tell people it is broken. And it can prevent it from being recommended again. -- Fengchao (talk) 10:30, 17 September 2012 (UTC)
Yes, please don't take example from what User:Danielwallace did; content should never be removed without at least a valid explanation in the edit summary, and anyway, in this case UNetbootin must be mentioned, even only as an non-recommended, discouraged alternative in a Warning: following the philosophy of the ArchWiki and Arch Linux in general, no available option must be hidden to the users, who are the only ones who can choose what's best for themselves in the end. -- Kynikos (talk) 13:22, 17 September 2012 (UTC)
Deletion reverted. Close. -- Fengchao (talk) 12:09, 24 September 2012 (UTC)
Reopening as the section has been restored. My opinion is unchanged. -- Kynikos (talk) 07:16, 20 April 2013 (UTC)
I'm sorry for re-opening the section but it was my first time that I wrote on this wiki. I know that UNetbooting overwrite the syslinux.cfg, infact my guide is to edit that file to permit the boot of the installation media. So I think you could remove the disclaimer. Mathias (talk) 14:44, 21 April 2013 (UTC)
Lol, silly me, I added the disclaimer back without re-reading the section just because I remembered this has been the cause of some edit warring in the past, sorry... Of course you're right, however I've merged the disclaimer into the introduction paragraph in order to try to prevent future disputes. Closed (again). -- Kynikos (talk) 10:57, 22 April 2013 (UTC)
It appears to me that there has been an increase in the number of new users attempting to use unetbootin (and failing) since this section was changed. I think this tool should be more strongly discuraged. There really is no reason to use it, even with the syslinux warning. I'd like to at least amplify the warning about using another tool, and ideally return the original warning from DSpider (Do Not Use UNETBOOTIN). 2ManyDogs (talk) 19:59, 13 June 2013 (UTC)
I admit it's been a while since I last tested UNetbootin: is the procedure described in the article working or not? In any case yes, please expand the warning about using another tool, specifying the reason why UNetbootin is worse. However let's not delete the section again, otherwise this cycle of deletions and restorations will never end... -- Kynikos (talk) 11:25, 15 June 2013 (UTC)