Freeing up space on root partition

NotionCommotion · 10-28-2016, 12:10 PM

As seen below, /dev/mapper/VolGroup-lv_root is full.

How do I view files in this partition so that I may delete some?
EDIT. Turns out I have a bunch of log fins in /var/log which were huge. I deleted some, and while I "fixed" the problem, I still would like to understand what this root partition represents.

If it turns out I need them all, how do I increase the size?

Thank you

Code:

[root@devserver ~]# df -aTh
Filesystem           Type         Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup-lv_root
                     ext4          50G   47G     0 100% /
proc                 proc            0     0     0    - /proc
sysfs                sysfs           0     0     0    - /sys
devpts               devpts          0     0     0    - /dev/pts
tmpfs                tmpfs        5.8G     0  5.8G   0% /dev/shm
/dev/sda1            ext4         477M  175M  278M  39% /boot
/dev/mapper/VolGroup-lv_home
                     ext4         985G   48G  887G   6% /home
/dev/mapper/VolGroup-lv_mysql
                     ext3          99G  498M   93G   1% /var/lib/mysql
none                 usbfs           0     0     0    - /home/vbox/vbusbfs
none                 binfmt_misc     0     0     0    - /proc/sys/fs/binfmt_misc
[root@devserver ~]#

dijetlo · 10-28-2016, 12:50 PM

Backup the data on VolGroup-lv-home - roughly 48 Gib - you could temporarily move it to /var/lib/mysql which is on VolGroup-lv-mysql and has 93 gig free

Reduce VolGoup-lv-home with lvreduce, I'd lop off everything but a couple of hundred gig, with lvm you can hold a reserve, which is handy. Auto installers use the entire disk, people who do it by hand always hold a little back for the problem your facing here (volume locked no-available-resource). The lvreduce will remove some of the space from the home volume (887Gib free). Your data should be preserved however a back-up is always a smart move (hence it was the first thing I asked you to do).

Extend VolGroup-lv-root whatever amount you need, the reserve you created with the lvreduce will more than cover a reasonable request.
Check that your data on your reduced volume remained intact or restore from lv-mysql if you have to. Delete the lv-home data that you moved to lv-sql when your done, regardless.

Commands to research:
lvreduce
lvextend

Hope that helps.

NotionCommotion · 10-28-2016, 01:46 PM

Thanks dijetlo,

How do I determine what directories are on this partition? For instance, it appears that all of /var/log is.

JeremyBoden · 10-28-2016, 01:52 PM

Code:

ls -l /

NotionCommotion · 10-28-2016, 02:09 PM

Quote:

Originally Posted by JeremyBoden

Code:

ls -l /

This shows all directories on all partitions, no?

Are all directories under root unless they are mounted elsewhere?

BW-userx · 10-28-2016, 02:29 PM

mount points are in fstab

suicidaleggroll · 10-28-2016, 03:08 PM

Look at your output of df. Any directories listed there (and their subdirectories, unless listed elsewhere) are on the associated mount point. Anything not shown falls on the all-encompassing "/".

In other words, take a directory. If it's not shown on df, then it will live on the same filesystem as its parent directory. If its parent directory is not shown on df, then it will live on the same filesystem as its parent directory, and so on until you get all the way back to "/".

dijetlo · 10-29-2016, 10:20 AM

Quote:

/dev/mapper/VolGroup-lv_root
ext4 50G 47G 0 100% /

The root lv (logical volume) in your implementation corresponds to '/' (the root directory). All other mounted file systems mount to this directory or one of its subdirectories.

Quote:

/dev/mapper/VolGroup-lv_home
ext4 985G 48G 887G 6% /home

That's lv home. It contains the home directory, '/home', and all sub directories.

Quote:

/dev/mapper/VolGroup-lv_mysql
ext3 99G 498M 93G 1% /var/lib/mysql

That's lv mysql. As you suggested it mounts to var, but it does so through a file branch path that doesn't touch var log
var:
- log:[ sys, mysql, ...]
- lib:[ -mysql <-- mount point is here ]

Good questions though, shows your thinking.