How to do a Filesystem Resize (ext3/ext4) on Redhat running on VMware

A filesystem resize can be done in several ways, online, offline, with LVM2 or without LVM2.  However, this blog will describe how to do an online resize of ext3/ext4 filesystems where a virtual disk (vmdk) is online added to a VMware Redhat guest OS.

So let’s start with the online filesystem resize of ext3/4 filesystems on the Redhat guest OS.  A new virutal disk (preferably an eagerd zero thick on VM running Oracle) was added as a pre requirement. Adding a new virtual disk is an online operation and no downtime is required to do it.

The whole procedure in this document is described by using the command line only. There is also a graphical user interface `system-config-lvm` that can perform the job, but that tool is out of scope in this document.

Online resize a ext3/4 filesystem

There are several steps that have to be done. These are in general:

  1. Scanning for new LUN’s
  2. Partition the new LUN’s and partprobe
  3. Create the physical volume
  4. Extend the volume group and the logical volume
  5. Extend the filesystem online

Rescan for new LUN’s

Depending on the number of virtual controllers, you have to scan for your new LUN’s on each of these. In case you know on which the disk was added, then of course, you need to scan only the appropriate one.

Rescan for new LUN’s on the first SCSI Controller (LSI Logic Parallel)

1
# echo "- - -"  > /sys/class/scsi_host/host0/scan*

Rescan for new LUN’s on the second SCSI Controller (Paravirtualized)

1
# echo "- - -"  > /sys/class/scsi_host/host1/scan*

Create a Primary Partion on the new devices

1
2
3
# fdisk /dev/sdx??
 
# fdisk /dev/sdy??

Partprobe the new devices

Partprobe is a program that informs the operating system kernel of partition table changes, by requesting that the operating system re-read the partition table.

1
2
3
# partprobe /dev/sdx??
 
# partprobe /dev/sdy??

Create the Pysical Volumes

1
2
3
# pvcreate /dev/sdx??
 
Physical volume "/dev/sdx??" successfully created
1
2
3
# pvcreate /dev/sdy??
 
Physical volume "/dev/sdy??" successfully created

Extend the Volume Group

1
2
3
# vgextend VGOracle /dev/sdx??
 
Volume group "VGOracle" successfully extended
1
2
3
# vgextend VGOracle /dev/sdy??
 
Volume group "VGOracle" successfully extended

Extend the Logical Volume

1
2
3
4
5
# lvextend -L 72G /dev/VGOracle/LVOracleu??
 
Extending logical volume LVOracleu?? to 72.00 GB
 
Logical volume LVOracleu01 successfully resized

Online Resize the ext3/ext4 Filesystem

After the logical volume is resized successfully, you can resize, in fact any filesystem that is online re-sizable. The following are examples for the ext3/ext4 filesystems. The syntax for ext3 and ext4 differ only slightly. For ext3 you use `resize2fs` even if its ext3 and not ext2, and in case of ext4 you use `resize4fs` were the command name is more logically.

ext3

1
# resize2fs /dev/VGOracle/LVOracleu??

ext4

1
# resize4fs /dev/VGOracle/LVOracleu??

 

That’s it. Now have fun with the bigger filesystem.

0 (0)
Article Rating (No Votes)
Rate this article
Attachments
There are no attachments for this article.
Comments
There are no comments for this article. Be the first to post a comment.
Full Name
Email Address
Security Code Security Code
Related Articles RSS Feed
Moving SSL Certificate from IIS to Apache
Viewed 2199 times since Mon, Feb 18, 2019
Do you Know These 5 Use of V$session View ?
Viewed 115501 times since Thu, Jun 21, 2018
7 Tips – Tuning Command Line History in Bash
Viewed 5733 times since Fri, Jul 5, 2019
www.unixarena.com
Viewed 2629 times since Fri, Jul 27, 2018
Terminal based "The Matrix" like implementation
Viewed 2519 times since Thu, Apr 18, 2019
Linux nslookup Command Examples for DNS Lookup
Viewed 9192 times since Sat, Sep 29, 2018
SYS: Configure a local repository. local repo
Viewed 11221 times since Mon, Oct 29, 2018
Linux Find Large Files
Viewed 3128 times since Mon, Oct 29, 2018
LVM: Reduce an existing Volume Group by removing one of its disks
Viewed 2683 times since Sat, Jun 2, 2018
LVM: Rename root VG/LV
Viewed 7907 times since Sat, Jun 2, 2018