June 2024


June 2024

Extended File System by adding a New Disk.

[root@myhost01 ~]# df -h Filesystem Size Used Avail Use% Mounted on /dev/mapper/VolGroup00-LogVol00 17G 13G 3.4G 79% / /dev/sda1 99M 43M 52M 45% /boot tmpfs 943M 0 943M 0% /dev/shm [root@myhost01 ~]# [root@myhost01 ~]# [root@myhost01 ~]# fdisk /dev/sdd Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel Building a new DOS […]

Converting a non-root filesystem to ext4

Before the Addition of new disk to the Linux Server : ============================================================================= ======>> The total number of disks on the system can be seen through fdisk -l

[root@servername ~]# fdisk -l | more

Disk /dev/sda: 21.4 GB, 21474836480 bytes 255 heads, 63 sectors/track, 2610 cylinders Units = cylinders of 16065 * 512 = […]

Converting a root filesystem to ext4

Converting a root filesystem is a bit more tricky because you cannot unmount it, as your system is running on it. Nevertheless it is still possible to do it without using an external bootable media. You should do this in a single-user mode.

First step is to modify your /etc/fstab file to say “ext4” […]

Linux File Systems: Ext2 vs Ext3 vs Ext4

EXT2, EXT3 and EXT4 are all filesystems created for Linux. This article explains the following:

High level difference between these filesystems. How to create these filesystems. How to convert from one filesystem type to another.

===>> Ext2

Ext2 stands for second extended file system. It was introduced in 1993. Developed by […]

Changing FS type from ext3 to ext4 in Linux

Now changing the ext3 FS to the ext4 FS type depends on the Requirement. =========================================================================

=====>> check the fs type by the below information

[root@servername ~]# mount | grep -i media

/dev/mapper/vg3-media1 on /media type ext3 (rw)

=====>> also check in the fstab file

[root@servername ~]# cat /etc/fstab /dev/vg0/root […]

CentOS 5: Converting Ext3 to Ext4

OS: CentOS 5.6 64bit Kernel version: 2.6.18-238.19.1.el5 Backup partition: /backup (mount from /dev/sdb)

1. First of all, its recommended to backup everything first. We will us ‘dd‘ command to backup the whole partition to another hard disk. That hard disk is attached via SATA cable. We will format the backup hard disk with […]

LINUX LVM multipath

krishbe$ multipath -ll mpath2 (360060480000190102091533030453034) dm-2 EMC,SYMMETRIX [size=30G][features=0][hwhandler=0][rw] \_ round-robin 0 [prio=2][active] \_ 0:0:0:112 sdd 8:48 [active][ready] \_ 3:0:0:112 sdg 8:96 [active][ready] mpath1 (360060480000190102091533030453033) dm-1 EMC,SYMMETRIX [size=30G][features=0][hwhandler=0][rw] \_ round-robin 0 [prio=2][active] \_ 0:0:0:111 sdc 8:32 [active][ready] \_ 3:0:0:111 sdf 8:80 [active][ready] mpath0 (360060480000190102091533030303830) dm-0 EMC,SYMMETRIX [size=2.8M][features=0][hwhandler=0][ro] \_ round-robin 0 [prio=2][active] \_ 0:0:0:0 sda 8:0 [active][ready] […]

Converting partitions from ext3 to ext4

The new features of ext4 over ext3 motivated me to migrate my ext3 partitions to the new file system. If you want to do the same, here’s the steps yo have to follow.

Converting from ext3 to ext4

Note: The following commands must be run on not mounted partitions. If you are planning to convert […]

Logical Volume Manager (LVM)

In the traditional disk partitioning scheme, administrators plan ahead the use of each partition. For instance, a laptop with 120 GB hard drive, 1 GB RAM can have the following partition scheme:

1 GB for swap (/dev/sda1), 12 GB for root (/dev/sda2), 107 GB for /home (/dev/sda3), meaning, the remaining space.

So far so […]

How to add LUN disk online under CentOS 6.2

Environment: CentOS 6.2 64bit with multipath connected to HP EVA storage, the LUN disk was LVM disk Objective: add a new LUN disk for server online and add into the existing LVM to make the partition size bigger scenario: LVM add new lun disk, increase the existing lvm lun disk, increase the existing partition disk […]