Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

I just installed Arch Linux on a server machine with a LSI hardware RAID 5.

During the installation, I created (and cfdisk properly reports) three partitions:

sda1 (/,     131G)
sda2 (/boot,   1G)
sda5 (swap,    4G)

Everything seems to be working fine, except that the df command is showing strange output:

Filesystem   1K-blocks   Used Available Use% Mounted on
tmpfs        131G        2.8G   121G     3%   /tmp
/dev/sda2    955M         50M   860M     6%   /boot

Note that at this point, /dev/sda2 isn't actually mounted... However, /dev/sda1 (my root partition) is missing, although it's definitely mounted. The readings for tmpfs would be correct if they were labeled "/dev/sda1". Likewise, the mount command (and /etc/mtab) displays:

tmpfs on /tmp type tmpfs (rw,nosuid,nodev)
/dev/sda2 on /boot type ext4 (rw)

Furthermore, I have a device sda3 in /dev/ which cfdisk doesn't know about.

In short:

  • /dev/sda1 doesn't show up anywhere
  • /dev/sda2 shows up without being mounted
  • /dev/sda3 exists but doesn't show up in 'cfdisk' (and has never been created) or 'df'
  • tmpfs is showing stats for /dev/sda1

This may be related to another issue I encounter during boot, see Strange boot behaviour

Any ideas on how to solve this?

share|improve this question
    
sda3 is probably the extended partition, which it seems cfdisk omits from its listing. –  psusi Jun 1 '12 at 14:50
add comment

1 Answer

You are most likely inside a "chroot" shell. The installer has done something like this:

mount /dev/sda1 /target
chroot /target

The chroot command creates a shell where /target is /. In that environment, the installer did mount /boot. Since this environment is not the one that mounted /, it doesn't end up in /etc/mtab but /boot does. I would assume however that if /proc is mounted in this environment, /proc/mounts might see the / mount.

share|improve this answer
    
Hey, you're right, /proc/mounts does see the / mount! However, I have rebooted the machine several times since installation, so I wouldn't expect to end up in a chrooted environment during normal boot. Any ideas? –  Philip Jun 1 '12 at 14:05
    
During boot, I also noticed strange behaviour, please see serverfault.com/questions/394721/strange-boot-behaviour I'm pretty confident that those two issues are somehow related. –  Philip Jun 1 '12 at 14:16
    
no, i wouldn't expect this to be the case during a normal boot, I would "During the installation". This is the case even when booting to the installed system? –  stew Jun 1 '12 at 14:35
    
Yes, it is. I boot the machine and it shows the behavior described above. –  Philip Jun 1 '12 at 14:37
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.