Why do I get an "Input/output error" when I try to copy some files from my ISO mount to /var/tmp

I mount the .iso file under /mnt and try to copy files from the isolinux directory to /var/tmp:

[root@localhost tmp]#  mount -o loop,ro  RedHat-5.8.1-01_x32.iso /mnt
[root@localhost tmp]# 
[root@localhost tmp]# cd /mnt
[root@localhost mnt]# cd isolinux  
[root@localhost isolinux]# ls
 boot.cat  general.msg  isolinux.bin  memtest      param.msg   splash.lss
 boot.msg  initrd.img   isolinux.cfg  options.msg  rescue.msg  vmlinuz
[root@localhost isolinux]# cp -rp vmlinuz initrd.img  /var/tmp
 cp: reading `vmlinuz': Input/output error
 cp: reading `initrd.img': Input/output error
  • 3
    It seems your ISO image is somehow corrupt. I tried this with a known-to-work Debian ISO image and it worked without problems. Incidentally, you don't really need the -r switch for your cp but that's not what's causing the problem.
    – Joseph R.
    Commented Oct 24, 2013 at 12:25
  • I agree that the most likely answer is corrupt media, but the next most likely, at least in my opinion, is a filesystem issue, especially considering the reference to loop mounts. Sometimes these things can happen post-kernel update if module links need remapping, and among the worst offenders are live union-type filesystems. Probably it's a bad iso, though.
    – mikeserv
    Commented Mar 6, 2014 at 4:52

1 Answer 1


IO Errors are almost always a sign of damaged media. I would try downloading it again.

  • This does not provide an answer to the question. To critique or request clarification from an author, leave a comment below their post - you can always comment on your own posts, and once you have sufficient reputation you will be able to comment on any post.
    – Anthon
    Commented Oct 24, 2013 at 15:23
  • 1
    @Anthon How is this not an answer?
    – phemmer
    Commented Mar 6, 2014 at 4:45
  • @Patrick I got this in the review queue. A) it is IMHO just a guess, and would therefore have been better suited as a comment; B) it added nothing to the already existing comment made by Joseph R.
    – Anthon
    Commented Mar 6, 2014 at 5:51
  • I disagree, though that is just my opinion. I would argue that all answers are just guesses. Until the asker selects an answer, we don't know which one is the right solution. Someone else coming in the future might have a problem which exhibits the same symptoms, but is solved by a different solution. In regards to adding nothing, I would argue that Joseph's comment should have been an answer. Since he didn't leave it as an answer, someone else did.
    – phemmer
    Commented Mar 6, 2014 at 6:10
  • 1
    I was highly skeptical... but this was my problem!
    – Mike Vella
    Commented Oct 12, 2017 at 14:19

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