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Attemping to install CentOS7 from usb but cannot

Posted: 2018/06/29 09:12:52
by miketh1234
Tried many different ways to accomplish this task but no success. Tried changing BIOS (Legacy and UEFI).

1) Starting Dracut Emergency Shell...

Warning: /dev/root/ does not exist

2) ERROR: could not insert 'floppy': No device found
ERROR: could not insert 'edd' : No device found

3) vmlinuz initrd=initrd.img inst.stage2=hd:LABEL=CENTOS\x20\x20x86_64 rd.live.check quiet

4) Gotten as far in the setup process but not able to choose a hard disk

Re: Attemping to install CentOS7 from usb but cannot

Posted: 2018/06/29 09:14:53
by TrevorH
How did you create your USB stick? A lot of the utilities that claim to do that actually break our iso images as they attempt to rewrite them while "copying" them. The best utility is plain old 'dd' as that doesn't attempt to be clever.

Information on USB key based installs can be found at http://wiki.centos.org/HowTos/InstallFromUSBkey

Re: Attemping to install CentOS7 from usb but cannot

Posted: 2018/06/29 10:52:14
by miketh1234
Trevor,

I will try 'dd' and follow up with you afterwards.

Thank you.

Re: Attemping to install CentOS7 from usb but cannot

Posted: 2018/06/29 11:20:23
by TrevorH
Also make sure you check the sha256sum of your downloaded file against the list published in our release notes to make sure your download is OK.

https://wiki.centos.org/Manuals/ReleaseNotes/CentOS7

Re: Attemping to install CentOS7 from usb but cannot

Posted: 2018/06/29 20:27:38
by lightman47
After an hour trying to get a working USB key, I surmised that the of= must be the /dev/{device} and NOT the path to the mounted point!!! In my case it was sdb1 - so my command was dd if=CentOS-7-x86_64-DVD-1804.iso of=/dev/sdb (just drop the "1" and commit the whole stick).

I found that out by running the 'disks' utility, then selecting the stick when it showed up after I plugged it in. In the right pane was it's /dev spec.

Hope this helps someone - I kept trying to "of=/run/media/user/directory". I now understand WHY some many people have the trouble I did getting a bootable stick.

;)

Re: Attemping to install CentOS7 from usb but cannot

Posted: 2018/10/14 14:47:55
by miketh1234
After taking the whole Summer off from installing (a full install) CentOS on a brand new Lenovo Windows 10 machine wondering if I could get some guidance from start to finish?
Question: Is it possible, and/or desirable, to use the Windows command line to "dd" a CentOS 7 iso image to my USB 3.1?

Re: Attemping to install CentOS7 from usb but cannot

Posted: 2018/10/14 16:20:30
by TrevorH
Question: Is it possible, and/or desirable, to use the Windows command line to "dd" a CentOS 7 iso image to my USB 3.1?
Yes and yes. Information on USB key based installs can be found at http://wiki.centos.org/HowTos/InstallFromUSBkey

Re: Attemping to install CentOS7 from usb but cannot

Posted: 2018/10/14 22:47:41
by miketh1234
Thank you for your timely reply but unfortunately I'm starting to wonder if I need step-by-step help because I am running into so many roadblocks. I do not have much experience with Windows. The reason I bought this computer was to use the Lenovo hardware and only use Linux-CentOS. Do you have any recommendations to get more specific help because I am not so sure that I will be able to accomplish this in this forum. Thank you very much.
Sincerely,
Michael Thomas

Re: Attemping to install CentOS7 from usb but cannot

Posted: 2018/10/14 23:28:04
by TrevorH
Start by downloading the iso image file then run a utility to get teh sha256sum of the file that you have. Compare that to the list of sha256sums that we publish in our wiki in the Release Notes for each release. Currently the wiki is broken so I ran sha256sum here against my copy and got 506e4e06abf778c3435b4e5745df13e79ebfc86565d7ea1e128067ef6b5a6345. If your downloaded iso image file sha256sum does not match that then download it again until it does.

When you dd that, make sure you write it to the entire USB device - in linux terms /dev/sdX - not to a partition on the device - i.e. not to /dev/sdX1. That iso image file should boot on both UEFI and legacy BIOS machines.

I believe that you can ignore errors about floppy and edd, those are just for information. The messages about missing /dev/root imply that it had trouble reading your installation media so if you haven't already done so, try a different USB stick and/or a different USB socket.

Re: Attemping to install CentOS7 from usb but cannot

Posted: 2019/02/08 21:41:06
by id2concept
For me sticking the USB drive in a USB 2 port instead of USB 3 did the job (Shuttle DH310).