/ disk size is running out of space and you need to extend the root disk size of a SLES VM without reboot.
This solution is tested for SLES VMs running on VMware with vmdk files for disk storage.
LVM, multipath, and other disk configurations are not covered in this solution.
1. Extend the disk size in VMware - edit settings of the VM and change the disk size. e.g. /dev/vda from 24GB to 48GB.
Note: If the VM has snapshot levels, you need to delete all snapshots before you can extend the disk size.
2. Check the disk size in the VM in running SLES system:
rescan-scsi-bus.sh --alltargetslocalhost:~ # lsblk /dev/vda
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINTS
vda 253:0 0 48G 0 disk
├─vda1 253:1 0 512M 0 part /boot/efi
├─vda2 253:2 0 20G 0 part /usr/local
│ /var
│ /tmp
│ /srv
│ /root
│ /opt
│ /home
│ /boot/grub2/x86_64-efi
│ /boot/grub2/i386-pc
│ /.snapshots
│ /
└─vda3 253:3 0 3.5G 0 part [SWAP]
The block device /dev/vda is now increased to 48GB.
For KVM and libvirt VMs after block device is increased you can use the following command to tell VM about the disk size change:
virsh blockresize --domain test1 vda --size 48GB3. Check the partition table:
fdisk -l /dev/vdafdisk -l /dev/vda
GPT PMBR size mismatch (50331647 != 100663295) will be corrected by write.
The backup GPT table is not on the end of the device.
Disk /dev/vda: 48 GiB, 51539607552 bytes, 100663296 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
Disklabel type: gpt
Disk identifier: 0754976C-FEE2-44EF-89A1-C580CDFD2EFD
Device Start End Sectors Size Type
/dev/vda1 2048 1050623 1048576 512M EFI System
/dev/vda2 1050624 42993663 41943040 20G Linux filesystem
/dev/vda3 42993664 50331614 7337951 3.5G Linux swap
We see that the disk size is increased to 48GB but the partition table is not updated yet. We have 3 partitions on the disk: vda1, vda2, vda3. The vda2 partition is the root partition which we want to extend.
But prior to extend the 2nd partition we need to temporarily remove the swap partition vda3.
4. Backup partition table:
sfdisk -d /dev/vda > /tmp/vda-partition-table.bak5. Disable swap:
swapoff /dev/vda36. Delete the swap partition:
fdisk /dev/vda
Welcome to fdisk (util-linux 2.37.4).
Changes will remain in memory only, until you decide to write them.
Be careful before using the write command.
GPT PMBR size mismatch (50331647 != 100663295) will be corrected by write.
The backup GPT table is not on the end of the device. This problem will be corrected by write.
This disk is currently in use - repartitioning is probably a bad idea.
It's recommended to umount all file systems, and swapoff all swap
partitions on this disk.
Command (m for help): p
Disk /dev/vda: 48 GiB, 51539607552 bytes, 100663296 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
Disklabel type: gpt
Disk identifier: 0754976C-FEE2-44EF-89A1-C580CDFD2EFD
Device Start End Sectors Size Type
/dev/vda1 2048 1050623 1048576 512M EFI System
/dev/vda2 1050624 42993663 41943040 20G Linux filesystem
/dev/vda3 42993664 50331614 7337951 3.5G Linux swap
Command (m for help): d
Partition number (1-3, default 3): 3
Partition 3 has been deleted.
Command (m for help):
Do not type "w" to write the changes yet. We need to extend the 2nd partition first.
7. Extend the 2nd partition: We need to first delete the 2nd partition and create it again.
Command (m for help): d
Partition number (1,2, default 2):
Partition 2 has been deleted.
Command (m for help): n
Partition number (2-128, default 2):
First sector (1050624-100663262, default 1050624):
Last sector, +/-sectors or +/-size{K,M,G,T,P} (1050624-100663262, default 100663262): +44G
Created a new partition 2 of type 'Linux filesystem' and of size 44 GiB.
Partition #2 contains a btrfs signature.
Do you want to remove the signature? [Y]es/[N]o: N
Command (m for help): 8. Check the partition table:
Command (m for help): p
Disk /dev/vda: 48 GiB, 51539607552 bytes, 100663296 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
Disklabel type: gpt
Disk identifier: 0754976C-FEE2-44EF-89A1-C580CDFD2EFD
Device Start End Sectors Size Type
/dev/vda1 2048 1050623 1048576 512M EFI System
/dev/vda2 1050624 93325311 92274688 44G Linux filesystem
Command (m for help):9. Create swap partition: So we create a new partition and take all remaining free space and toggle the partition type from "Linux filesystem" to "Linux swap".
Command (m for help): n
Partition number (3-128, default 3):
First sector (93325312-100663262, default 93325312):
Last sector, +/-sectors or +/-size{K,M,G,T,P} (93325312-100663262, default 100663262):
Created a new partition 3 of type 'Linux filesystem' and of size 3.5 GiB.
Command (m for help): t
Partition number (1-3, default 3):
Partition type or alias (type L to list all): swap
Changed type of partition 'Linux filesystem' to 'Linux swap'.
Command (m for help): 10. Review the partition table:
Command (m for help): p
Disk /dev/vda: 48 GiB, 51539607552 bytes, 100663296 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
Disklabel type: gpt
Disk identifier: 0754976C-FEE2-44EF-89A1-C580CDFD2EFD
Device Start End Sectors Size Type
/dev/vda1 2048 1050623 1048576 512M EFI System
/dev/vda2 1050624 93325311 92274688 44G Linux filesystem
/dev/vda3 93325312 100663262 7337951 3.5G Linux swap
Command (m for help):11. Write the changes to disk:
Command (m for help): w
The partition table has been altered.
Syncing disks.
localhost:~ # 12. Resize the filesystem: In case of filesystem ext3/4 use this command:
resize2fs /dev/vda2In case of filesystem xfs use this command:
xfs_growfs /dev/vda2In case of btrfs filesystem use this command:
btrfs filesystem resize max /13. Activate swap:
mkswap /dev/vda3
swapon /dev/vda3mkswap generates new partion UUID which must be updated in /etc/fstab.
mkswap /dev/vda3
Setting up swapspace version 1, size = 3.5 GiB (3757023232 bytes)
no label, UUID=41a063c1-6b88-40a0-bf03-fad15a0a1b73
Update /etc/fstab with the new UUID:
vi /etc/fstab
UUID=41a063c1-6b88-40a0-bf03-fad15a0a1b73 swap swap defaults 0 014. Check the disk size:
lsblk
df -hT
free -mSample output from btrfs filesystem after resizing:
df -hT
Filesystem Type Size Used Avail Use% Mounted on
devtmpfs devtmpfs 4.0M 0 4.0M 0% /dev
tmpfs tmpfs 2.6G 4.0K 2.6G 1% /dev/shm
tmpfs tmpfs 710M 9.1M 701M 2% /run
tmpfs tmpfs 4.0M 0 4.0M 0% /sys/fs/cgroup
/dev/vda2 btrfs 44G 2.6G 42G 6% /
/dev/vda2 btrfs 44G 2.6G 42G 6% /.snapshots
/dev/vda2 btrfs 44G 2.6G 42G 6% /boot/grub2/i386-pc
/dev/vda2 btrfs 44G 2.6G 42G 6% /boot/grub2/x86_64-efi
/dev/vda2 btrfs 44G 2.6G 42G 6% /home
/dev/vda2 btrfs 44G 2.6G 42G 6% /opt
/dev/vda2 btrfs 44G 2.6G 42G 6% /root
/dev/vda2 btrfs 44G 2.6G 42G 6% /srv
/dev/vda2 btrfs 44G 2.6G 42G 6% /tmp
/dev/vda2 btrfs 44G 2.6G 42G 6% /var
/dev/vda2 btrfs 44G 2.6G 42G 6% /usr/local
/dev/vda1 vfat 511M 5.1M 506M 1% /boot/efi
tmpfs tmpfs 355M 4.0K 355M 1% /run/user/015. Done.