How to shrink or grow an xfs filesystem

Shrink

## take note the logical volume details and confirm it is formatted with xfs [root@rhel7sat1 ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 200G 0 disk ├─sda1 8:1 0 1G 0 part /boot └─sda2 8:2 0 199G 0 part ├─rhel-root 253:0 0 50G 0 lvm / ├─rhel-swap 253:1 0 7.9G 0 lvm [SWAP] └─rhel-home 253:2 0 141.1G 0 lvm /home sr0 11:0 1 57.7M 0 rom [root@rhel7sat1 ~]# grep \/home /etc/fstab /dev/mapper/rhel-home /home xfs defaults 0 0## We want to shrink /dev/rhel/home currently using 141g and mounted on /home ## (1). Take backup of the filesystem using xfsdump [root@rhel7sat1 ~]# xfsdump -f /var/tmp/home-xfs.dump /home xfsdump: using file dump (drive_simple) strategy xfsdump: version 3.1.7 (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 rhel7sat1:/home xfsdump: dump date: Wed Jul 22 10:48:37 2020 xfsdump: session id: 768efc3e-737c-44d4-a71f-07523bd15e12 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: 35328 bytes ============================= 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 27552 bytes xfsdump: dump size (non-dir files) : 1632 bytes xfsdump: dump complete: 3 seconds elapsed xfsdump: Dump Summary: xfsdump: stream 0 /var/tmp/home-xfs.dump OK (success) xfsdump: Dump Status: SUCCESS ## (2) unmount[root@rhel7sat1 ~]# umount /home ## (3) reduce the logical volume [root@rhel7sat1 ~]# lvreduce -L 9G /dev/rhel/home WARNING: Reducing active logical volume to 9.00 GiB. THIS MAY DESTROY YOUR DATA (filesystem etc.) Do you really want to reduce rhel/home? [y/n]: y Size of logical volume rhel/home changed from 10.00 GiB (2560 extents) to 9.00 GiB (2304 extents). Logical volume rhel/home successfully resized ## (4) reformat the reduced LVM to xfs [root@rhel7sat1 ~]# mkfs.xfs -f /dev/rhel/home meta-data=/dev/rhel/home isize=512 agcount=4, agsize=589824 blks = sectsz=512 attr=2, projid32bit=1 = crc=1 finobt=0, sparse=0 data = bsize=4096 blocks=2359296, imaxpct=25 = sunit=0 swidth=0 blks naming =version 2 bsize=4096 ascii-ci=0 ftype=1 log =internal log bsize=4096 blocks=2560, version=2 = sectsz=512 sunit=0 blks, lazy-count=1 realtime =none extsz=4096 blocks=0, rtextents=0 ## (5) re-mount [root@rhel7sat1 ~]# mount /dev/rhel/home /home [root@rhel7sat1 ~]# df -h /home Filesystem Size Used Avail Use% Mounted on /dev/mapper/rhel-home 9.0G 33M 9.0G 1% /home ## (6) restore from dump [root@rhel7sat1 ~]# xfsrestore -f /var/tmp/home-xfs.dmp /home xfsrestore: using file dump (drive_simple) strategy xfsrestore: version 3.1.7 (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: rhel7sat1 xfsrestore: mount point: /home xfsrestore: volume: /dev/mapper/rhel-home xfsrestore: session time: Wed Jul 22 11:13:15 2020 xfsrestore: level: 0 xfsrestore: session label: "home" xfsrestore: media label: "home" xfsrestore: file system id: 82825a22-5e1e-4ea6-bde9-38077a069767 xfsrestore: session id: 9ab9dda5-52a9-446b-9380-f60cafdd5c21 xfsrestore: media id: 797cce91-d6c8-4d03-94b0-edd03bda3b90 xfsrestore: using online session inventory xfsrestore: searching media for directory dump xfsrestore: reading directories xfsrestore: 5 directories and 7 entries processed xfsrestore: directory post-processing xfsrestore: restoring non-directory files xfsrestore: restore complete: 0 seconds elapsed xfsrestore: Restore Summary: xfsrestore: stream 0 /var/tmp/home-xfs.dmp OK (success) xfsrestore: Restore Status: SUCCESS

Grow

## Scenario 1 : Add another partition ## Firstly follow his guide to extend the disk ## assuming the Volume group (vg) is rhel and the Logical volume is var ## Create the partition e.g. for GPT formatted disk, using gdisk, for MBR formatted disk, using fdisk gdisk /dev/sda Command (? for help): n Partition number (4-128, default 4): Enter First sector .... : Enter Last sector ..... : Enter Current type is 'Linux filesystem' Hex code or GUID (L to show codes, Enter = 8300):Enter
Command (? for help): w Final checks complete. About to write GPT data. THIS WILL OVERWRITE EXISTING PARTITIONS!! Do you want to proceed? (Y/N): Y ## do a partprobe to rescan the disk and detect the new partition partprobe ## assuming the new partition was partition 4 pvcreate /dev/sda4 vgextend vgname /dev/sda4 lvextend -l +100%FREE /dev/rhel/var ## resize the filesystem, for XFS, use xfs_growfsxfs_growfs /dev/rhel/var## Scenario 2 : Add another disk e.g. /dev/sdbpvcreate /dev/sdbvgextend vgname /dev/sdb lvextend -l +100%FREE /dev/rhel/var ## resize the filesystem, for XFS, use xfs_growfs xfs_growfs /dev/rhel/var