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I moved the /var directory to a new disk/partition, this part worked well, but I forgot to delete/move the old /var path and it is still using space on / (root) partition. How could I delete the old /var without redo all the process? Any ideas?

This is what I did so far:

fdisk -l
mount /dev/sdb /mnt/newvar/
df -h /mnt/newvar/
rsync -aqxP /var/* /mnt/newvar/
umount /mnt/newvar/  /mnt/var/
umount /mnt/newvar/
umount /disk2/
umount /mnt/newvar/
ls -la /mnt/newvar/
df -h
vim /etc/fstab

fstab content:

UUID=c7c73822-b6e8-4aa4-a4b2-41a70c29568f /boot ext2 defaults 0 2
/dev/mapper/zabbix--vg-swap_1 none swap sw 0 0
/dev/fd0 /media/floppy0 auto rw,user,noauto,exec,utf8 0       0
UUID="3195ad53-3aaa-418c-bdc0-d341e33d76d3" /var ext3 defaults 0 2

Result of the above command:

df -P / /var

Filesystem                  1024-blocks     Used Available Capacity Mounted on
/dev/mapper/zabbix--vg-root    11758232 10103908   1033988      91% /
/dev/sdb                       25671996  8720916  15640360      36% /var
AdminBee
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Leonardo L. Southier
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  • Welcome to StackExchange! Have you ever deleted a directory before? Please edit your question to show what you have tried that isn't working for you in this case. – Jim L. Oct 06 '21 at 15:32
  • Check the old /var isn't mounted, but the new one is. – Jeremy Boden Oct 06 '21 at 15:33
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    Can you show us the layout, a bit better? are you mounting the the partition at the /var mountpoint? – polemon Oct 06 '21 at 15:34
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    -1 for providing very little information, please EDIT and push more info in – Vlastimil Burián Oct 06 '21 at 17:16
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    Adding to the comment by @LinuxSecurityFreak, the output of df -P / /var would confirm that you have /var on a different partition. – doneal24 Oct 06 '21 at 17:59
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    @JimL., they have filesystem A, containing the root filesystem, and including /var. Then they make filesystem B, containing only the contents of /var, and mount that on /var. Now the contents of /var on filesystem A are not visible, since fs B is mounted on top of that. Deleting /var would remove the contents of B, probably causing some trouble, but would leave the now useless "invisible" stuff in place. So no, you can't look at that as just deleting a directory. – ilkkachu Oct 06 '21 at 18:13
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    The intent was to get the user to add more detail about the steps taken so far, and the actual point of trouble. With respect, @ilkkachu, your conjecture may be accurate, but it is conjecture none the less. – Jim L. Oct 06 '21 at 18:20
  • You actually have a /dev/fd0 on your system? Haven't seen an automounted floppy drive in a while. – doneal24 Oct 06 '21 at 18:39
  • This is a sequencing confusion. During system startup, /var is created and used before /dev/sdb is available. Moving /var doesn't seem like the best choice. Read man hier or https://www.man7.org/linux/man-pages/man7/hier.7.html – waltinator Oct 06 '21 at 21:28
  • @waltinator Having the operating system spread out over several disks has been around forever. All of the /dev/sd? devices become available to initrd at the same time. – doneal24 Oct 07 '21 at 12:28
  • If the answer below was useful, please consider accepting it so that it will show up in future searches. – doneal24 Oct 07 '21 at 14:47

1 Answers1

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You can use a bind mount to access the original device. This does assume that the new /var is on a different partition.

mountpoint /var   # confirm that /var is mounted on a different partition. If not, STOP NOW
mkdir /mnt/root
mount --bind / /mnt/root
ls -lid /var /mnt/root/var    # these will be different inodes
ls /var /mnt/root/var   # different file contents if you've updated /var
rm -rf /mnt/root/var
mkdir /mnt/root/var
umount /mnt/root
rmdir /mnt/root

As usually suggested, back everything up before trying this Just as a suggestion to your new configuration. You did not do anything wrong but I would not have done it your way.

First suggestion: you should probably have made a partition in /dev/sdb and created your file system in /dev/sdb1. Maybe pedantic but I don't like using the disk volumes for file systems. Have had problems with this in the past.

Second: you could have created a PV volume on /dev/sdb1 and added that to /dev/mapper/zabbix to extend the volume. This would have put the entire LVM partition on two disks which will increase the probability of data loss if a disk dies but you would not have needed to move any data. However, if a disk dies in your setup you're probably hosed anyway so that is what backups are for.

doneal24
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