Summary
If you require to shrink the file system with xfs format, unfortunately there is no method to do so, in my case, the /root and /home system was installed in the LVM, and with xfs file system, cannot do much to /root system, dumped out /home file system, format and shrank the file system and restored the /home system.
Problem:No free sectors available
After working with RHEL 7 for quite some time, found I may need to create a new partition, however found out my LVM filled the whole file system, as below fdisk -l command shows,
[root@localhost ~]# fdisk -l
Disk /dev/sda: 171.8 GB, 171798691840 bytes, 335544320 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x0007f14e
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 1026047 512000 83 Linux
/dev/sda2 1026048 335544319 167259136 8e Linux LVM
Disk /dev/mapper/rhel-root: 53.7 GB, 53687091200 bytes, 104857600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/mapper/rhel-swap: 2147 MB, 2147483648 bytes, 4194304 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk /dev/mapper/rhel-home: 115.4 GB, 115368525824 bytes, 225329152 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
[root@localhost ~]#Tried to create new partition with fail result, as below shows,
[root@localhost ~]# fdisk /dev/sda
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Command (m for help): n
Partition type:
p primary (2 primary, 0 extended, 2 free)
e extended
Select (default p): p
Partition number (3,4, default 3):
No free sectors available
Command (m for help):
Found my file system root and home filled the whole disk, and with xfs format in LVM,
[root@localhost ~]# mount -l | grep mapper
/dev/mapper/rhel-root on / type xfs (rw,relatime,seclabel,attr2,inode64,noquota)
/dev/mapper/rhel-home on /home type xfs (rw,relatime,seclabel,attr2,inode64,noquota)
[root@localhost ~]#[root@localhost /]# umount /home
umount: /home: target is busy.
(In some cases useful info about processes that use
the device is found by lsof(8) or fuser(1))
[root@localhost /]#
For xfs format, you cannot use e2fsck and lvreduce to reduce the size, that is for ext2 format, as below command shows,
[root@localhost Desktop]# mount | grep mapper
/dev/mapper/rhel-root on / type xfs (rw,relatime,seclabel,attr2,inode64,noquota)
/dev/mapper/rhel-home on /home type xfs (rw,relatime,seclabel,attr2,inode64,noquota)
[root@localhost Desktop]# umount /home
[root@localhost Desktop]# cd
[root@localhost ~]# e2fsck -f /dev/mapper/rhel-home
e2fsck 1.42.9 (28-Dec-2013)
ext2fs_open2: Bad magic number in super-block
e2fsck: Superblock invalid, trying backup blocks...
e2fsck: Bad magic number in super-block while trying to open /dev/mapper/rhel-home
The superblock could not be read or does not describe a correct ext2
filesystem. If the device is valid and it really contains an ext2
filesystem (and not swap or ufs or something else), then the superblock
is corrupt, and you might try running e2fsck with an alternate superblock:
e2fsck -b 8193 <device>df -hT command shows the root and home file system is xfs.
[root@localhost ~]# df -hT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/rhel-root xfs 50G 5.7G 45G 12% /
devtmpfs devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs tmpfs 1.9G 140K 1.9G 1% /dev/shm
tmpfs tmpfs 1.9G 9.0M 1.9G 1% /run
tmpfs tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sda1 xfs 497M 159M 339M 32% /boot
.host:/ vmhgfs 120G 110G 9.4G 93% /mnt/hgfs
tmpfs tmpfs 378M 16K 378M 1% /run/user/0
/dev/mapper/rhel-home xfs 108G 338M 108G 1% /homeinstall xfsdump
[root@localhost ~]# yum install xfsdump -ydump the home system to /tem/home.dump
[root@localhost ~]# xfsdump -f /tmp/home.dump /home
xfsdump: using file dump (drive_simple) strategy
xfsdump: version 3.1.4 (dump format 3.0) - type ^C for status and control
============================= dump label dialog ==============================
please enter label for this dump session (timeout in 300 sec)
-> home
session label entered: "home"
--------------------------------- end dialog ---------------------------------
xfsdump: level 0 dump of localhost.localdomain:/home
xfsdump: dump date: Fri Aug 19 09:25:06 2016
xfsdump: session id: ded77b0c-052a-4d97-b836-5e55d9fc8c8e
xfsdump: session label: "home"
xfsdump: ino map phase 1: constructing initial dump list
xfsdump: ino map phase 2: skipping (no pruning necessary)
xfsdump: ino map phase 3: skipping (only one dump stream)
xfsdump: ino map construction complete
xfsdump: estimated dump size: 318958656 bytes
xfsdump: /var/lib/xfsdump/inventory created
============================= media label dialog =============================
please enter label for media in drive 0 (timeout in 300 sec)
-> home
media label entered: "home"
--------------------------------- end dialog ---------------------------------
xfsdump: creating dump session media file 0 (media 0, file 0)
xfsdump: dumping ino map
xfsdump: dumping directories
xfsdump: dumping non-directory files
xfsdump: ending media file
xfsdump: media file size 316926432 bytes
xfsdump: dump size (non-dir files) : 314043752 bytes
xfsdump: dump complete: 103 seconds elapsed
xfsdump: Dump Summary:
xfsdump: stream 0 /tmp/home.dump OK (success)
xfsdump: Dump Status: SUCCESSumount /home, delete, create and format with shrank size
[root@localhost ~]# cd /
[root@localhost /]# umount /home
[root@localhost /]# lvremove /dev/rhel/home
Do you really want to remove active logical volume home? [y/n]: y
Logical volume "home" successfully removed
[root@localhost /]# lvcreate --name home -L 10G rhel
WARNING: xfs signature detected on /dev/rhel/home at offset 0. Wipe it? [y/n]: y
Wiping xfs signature on /dev/rhel/home.
Logical volume "home" created.
[root@localhost /]# mkfs.xfs /dev/rhel/home
meta-data=/dev/rhel/home isize=256 agcount=4, agsize=655360 blks
= sectsz=512 attr=2, projid32bit=1
= crc=0 finobt=0
data = bsize=4096 blocks=2621440, imaxpct=25
= sunit=0 swidth=0 blks
naming =version 2 bsize=4096 ascii-ci=0 ftype=0
log =internal log bsize=4096 blocks=2560, version=2
= sectsz=512 sunit=0 blks, lazy-count=1
realtime =none extsz=4096 blocks=0, rtextents=0mount, restore /home
[root@localhost /]# mount /dev/rhel/home /home/
[root@localhost /]# xfsrestore -f /tmp/home.dump /home/
xfsrestore: using file dump (drive_simple) strategy
xfsrestore: version 3.1.4 (dump format 3.0) - type ^C for status and control
xfsrestore: searching media for dump
xfsrestore: examining media file 0
xfsrestore: dump description:
xfsrestore: hostname: localhost.localdomain
xfsrestore: mount point: /home
xfsrestore: volume: /dev/mapper/rhel-home
xfsrestore: session time: Fri Aug 19 09:25:06 2016
xfsrestore: level: 0
xfsrestore: session label: "home"
xfsrestore: media label: "home"
xfsrestore: file system id: 0e987d74-044d-4557-a315-16b1e85f0385
xfsrestore: session id: ded77b0c-052a-4d97-b836-5e55d9fc8c8e
xfsrestore: media id: d1449ee8-f7d2-44ca-8cfc-d4d5c9e86810
xfsrestore: using online session inventory
xfsrestore: searching media for directory dump
xfsrestore: reading directories
xfsrestore: 971 directories and 4348 entries processed
xfsrestore: directory post-processing
xfsrestore: restoring non-directory files
xfsrestore: restore complete: 1 seconds elapsed
xfsrestore: Restore Summary:
xfsrestore: stream 0 /tmp/home.dump OK (success)
xfsrestore: Restore Status: SUCCESS
[root@localhost /]# cd /home/
[root@localhost home]# ls -lah
total 8.0K
drwxr-xr-x. 4 root root 36 Aug 19 09:32 .
dr-xr-xr-x. 20 root root 4.0K Aug 19 04:02 ..
drwx------. 3 admin admin 74 Aug 17 13:21 admin
drwx------. 18 xionghuilin xionghuilin 4.0K Aug 18 20:10 xionghuilin
[root@localhost home]# successful result, reduced to 10G from 108G
[root@localhost home]# df -hT
Filesystem Type Size Used Avail Use% Mounted on
/dev/mapper/rhel-root xfs 50G 6.0G 44G 12% /
devtmpfs devtmpfs 1.9G 0 1.9G 0% /dev
tmpfs tmpfs 1.9G 140K 1.9G 1% /dev/shm
tmpfs tmpfs 1.9G 9.0M 1.9G 1% /run
tmpfs tmpfs 1.9G 0 1.9G 0% /sys/fs/cgroup
/dev/sda1 xfs 497M 159M 339M 32% /boot
.host:/ vmhgfs 120G 111G 8.9G 93% /mnt/hgfs
tmpfs tmpfs 378M 16K 378M 1% /run/user/0
/dev/sr0 iso9660 3.8G 3.8G 0 100% /var/ftp/dvd
/dev/mapper/rhel-home xfs 10G 338M 9.7G 4% /home
[root@localhost home]# problem still exist, cannot create new partition
The problem is, I still cannot create new partition, for example /dev/sda3, as all the space had been used by /dev/sda2, the LVM partition, and I cannot do much about it, as the /root file system was inside this partition. I have tried to remove the partition and re-create the partition, without touch to the /root file system, however when reboot, the /root file system cannot be mounted.
[root@localhost ~]# pvs
PV VG Fmt Attr PSize PFree
/dev/sda2 rhel lvm2 a-- 159.51g 97.51g
[root@localhost ~]# vgs
VG #PV #LV #SN Attr VSize VFree
rhel 1 3 0 wz--n- 159.51g 97.51g
[root@localhost ~]# lvs
LV VG Attr LSize Pool Origin Data% Meta% Move Log Cpy%Sync Convert
home rhel -wi-ao---- 10.00g
root rhel -wi-ao---- 50.00g
swap rhel -wi-ao---- 2.00g
[root@localhost ~]#
[root@localhost ~]# lvdisplay
--- Logical volume ---
LV Path /dev/rhel/swap
LV Name swap
VG Name rhel
LV UUID zMMtLu-h7Kq-eA5N-RUGw-YHk8-uifN-vVm4Hd
LV Write Access read/write
LV Creation host, time localhost, 2016-08-11 16:15:48 +0800
LV Status available
# open 2
LV Size 2.00 GiB
Current LE 512
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:1
--- Logical volume ---
LV Path /dev/rhel/root
LV Name root
VG Name rhel
LV UUID jOUoWU-uBpc-QLOs-Ffb7-9dGU-ELZU-FSncyC
LV Write Access read/write
LV Creation host, time localhost, 2016-08-11 16:15:49 +0800
LV Status available
# open 1
LV Size 50.00 GiB
Current LE 12800
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:0
--- Logical volume ---
LV Path /dev/rhel/home
LV Name home
VG Name rhel
LV UUID dy5XUG-LGjc-tUDP-7fp7-sGR3-LTd1-sp9G0w
LV Write Access read/write
LV Creation host, time localhost.localdomain, 2016-08-19 09:30:25 +0800
LV Status available
# open 1
LV Size 10.00 GiB
Current LE 2560
Segments 1
Allocation inherit
Read ahead sectors auto
- currently set to 8192
Block device 253:2
[root@localhost ~]# vgdisplay
--- Volume group ---
VG Name rhel
System ID
Format lvm2
Metadata Areas 1
Metadata Sequence No 6
VG Access read/write
VG Status resizable
MAX LV 0
Cur LV 3
Open LV 3
Max PV 0
Cur PV 1
Act PV 1
VG Size 159.51 GiB
PE Size 4.00 MiB
Total PE 40834
Alloc PE / Size 15872 / 62.00 GiB
Free PE / Size 24962 / 97.51 GiB
VG UUID FY15EN-79eI-MDry-uQgW-LZ7u-mdRT-SJMLr9below action will crash the /root system
I followed to this Link to shrink the lvm size, have tested, /root system crashed, not sure how to solve this problem…
[root@localhost ~]# fdisk /dev/sda
Welcome to fdisk (util-linux 2.23.2).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
Command (m for help): p
Disk /dev/sda: 171.8 GB, 171798691840 bytes, 335544320 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x0007f14e
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 1026047 512000 83 Linux
/dev/sda2 1026048 335544319 167259136 8e Linux LVM
Command (m for help): d
Partition number (1,2, default 2): 2
Partition 2 is deleted
Command (m for help): n
Partition type:
p primary (1 primary, 0 extended, 3 free)
e extended
Select (default p): p
Partition number (2-4, default 2):
First sector (1026048-335544319, default 1026048):
Using default value 1026048
Last sector, +sectors or +size{K,M,G} (1026048-335544319, default 335544319): +80G
Partition 2 of type Linux and of size 80 GiB is set
Command (m for help): m
Command action
a toggle a bootable flag
b edit bsd disklabel
c toggle the dos compatibility flag
d delete a partition
g create a new empty GPT partition table
G create an IRIX (SGI) partition table
l list known partition types
m print this menu
n add a new partition
o create a new empty DOS partition table
p print the partition table
q quit without saving changes
s create a new empty Sun disklabel
t change a partition\'s system id
u change display/entry units
v verify the partition table
w write table to disk and exit
x extra functionality (experts only)
Command (m for help): t
Partition number (1,2, default 2): 2
Hex code (type L to list all codes): 8e
Changed type of partition \'Linux\' to \'Linux LVM\'
Command (m for help): p
Disk /dev/sda: 171.8 GB, 171798691840 bytes, 335544320 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x0007f14e
Device Boot Start End Blocks Id System
/dev/sda1 * 2048 1026047 512000 83 Linux
/dev/sda2 1026048 168798207 83886080 8e Linux LVM
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table. The new table will be used at
the next reboot or after you run partprobe(8) or kpartx(8)
Syncing disks.
[root@localhost ~]#Refernce
1, Youtube: Shrink an XFS partition
2, LVM Partition Resizing