On 7 February 2011 15:55, Jerry Geis geisj@pagestation.com wrote:

What will be the correct way to migrate ext3 to ext4 going from 5.5 to 5.6? Will something after the update ask if you want to migrate the file systems? Looking forward to some file system speed ups with large files.

Thanks

Jerry _______________________________________________ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos

Based on experienced with other systems (ubuntu etc) a rebuild would be teh best way if you want to move from one to the other (or a full backup of disk then restore all the files) due to existing files on the ext3 system not gaining the benefits from ext4 - only new files.

Personally I'm skipping such an extensive change until Centos 6 is due and I'll need to test on that anyway - and can verify an appropriate ext4 configuration at the some time.

James

-----Original Message----- From: centos-bounces@centos.org [mailto:centos-bounces@centos.org] On Behalf Of Jerry Geis Sent: Monday, February 07, 2011 10:55 AM To: CentOS ML Subject: [CentOS] premature question on 5.6

What will be the correct way to migrate ext3 to ext4 going from 5.5 to 5.6? Will something after the update ask if you want to migrate the file systems? Looking forward to some file system speed ups with large files.

Google convert ext3 to ext4 centos

Hit 1: https://www.centos.org/modules/newbb/viewtopic.php?topic_id=26324 contains yum -y install e4fsprogs vi /etc/fstab (change ext3 to ext4 for my / partition) mkinitrd --with=ext4 --with=ext3 -f /boot/initrd-2.6.18-194.3.1.el5.img 2.6.18-194.3.1 tune4fs -O extents,uninit_bg,dir_index /dev/mapper/VolGroup00-LogVolRoot shutdown -r now (reboot from DVD with linux rescue) fsck -t ext4 -pf /dev/mapper/VolGroup00-LogVolRoot (this failed for me so I had to then run...) fsck -t ext4 -f /dev/mapper/VolGroup00-LogVolRoot (answer Y to the questions about fixing it) (reboot back into normal boot)

Hit 2: https://www.centos.org/modules/newbb/viewtopic.php?topic_id=26324 Entire page

Hit 3: http://www.linuxquestions.org/questions/linux-general-1/convert-ext3-to- ext4-794210/ Using tune2fs should work just fine. There's a nice little guide at http://ext4.wiki.kernel.org/index.ph...system_to_ext4 and a more complete one at http://www.cyberciti.biz/tips/linux-...le-system.html

Hit 4: http://planet.admon.org/convert-file-system-from-ext3-to-ext4/ (the age of this hit is indeterminate, so the 'advice' to keep /boot in ext3 is of unknown necessity) Once you converted your file system to ext4, the fs cannot be mounted as ext3. Note that ext4 may have some bugs so do not use it on productive servers. It's also recommended that keep your /boot in ext3.

You need to check ext4 is supported and compiled in you current kernel. Otherwise, you need to apply the patch, and re-compile your kernel. I assume that your kernel supports ext4. Simply follow these steps to convert an existing ext3 file-system to ext4. For example, in order to converting /dev/sdb1 to ext4, you need to type: # cd /; umount /dev/sdb1 # tune2fs -O extents,uninit_bg,dir_index /dev/sdb1 # fsck -pf /dev/sdb1

Now, all's OK, just mount it as ext4:

mount -t ext4 /dev/sdb1 /ext4

If you have converted /boot file system , you need to update /boot/grub.conf. Use your favourite editor to open this file, find out current kernel config section and append the following parameter: rootfstype=ext4

Here is sample config:

title Ubuntu 8.10, kernel 2.6.28.1 root (hd0,1) kernel /boot/vmlinuz-2.6.28.1 ro quiet splash rootfstype=ext4 initrd /boot/initrd.img-2.6.28.1 Quiet

Sounds pretty do-able.

/me ******************************************************************* This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This footnote also confirms that this email message has been swept for the presence of computer viruses. www.Hubbell.com - Hubbell Incorporated**