028 to 042 kernel upgrade - Revision history

79.112.22.184 at 13:21, 26 May 2015

2015-05-26T13:21:01Z

79.112.22.184: edit for swraid bitmap small chunk

2015-05-26T13:19:29Z

edit for swraid bitmap small chunk

Kir: add -p to fsck.ext4

2015-01-29T17:08:11Z

add -p to fsck.ext4

Kir: /* Create new initrd with proper modules */ simplify mkinitrd command

2013-11-21T04:03:10Z

‎Create new initrd with proper modules: simplify mkinitrd command

Kir: improvements all over the place (apparently live cd is optional)

2013-11-21T03:54:40Z

improvements all over the place (apparently live cd is optional)

Paparaciz: now should look better

2013-10-30T07:32:18Z

now should look better

Paparaciz: fix link to user page

2013-10-30T07:24:20Z

fix link to user page

Kir: created (stolen from https://openvz.org/User_talk:Denis_Hohryakov)

2013-10-29T21:44:51Z

created (stolen from https://openvz.org/User_talk:Denis_Hohryakov)

New page

This article describes a way to upgrade your old OpenVZ system with RHEL5-based
(028stabNNN kernel) to RHEL6-based (042stabNNN) kernel, and convert /vz
from ext3 to ext4.

Assumptions:
* systems is CentOS (RHEL) 5.x
* vzkernel is 028stabXXX, i.e. RHEL5-based
* /vz uses ext3

End result should be:
* Same CentOS 5 system
* vzkernel is 042stabXXX
* /vz uses ext4

== Update your system ==

yum update

== Add rhel6 kernel repos ==

Disable rhel5 and enable rhel6 OpenVZ kernel repository.
In other words, change <code>/etc/yum.repos.d/openvz.repo</code>
to look like this (changes required are '''in bold'''):

[openvz-kernel-rhel6]
name=OpenVZ RHEL6-based stable kernels
<nowiki>#baseurl=http://download.openvz.org/kernel/branches/rhel6-2.6.32/current/</nowiki>
<nowiki>mirrorlist=http://download.openvz.org/kernel/mirrors-rhel6-2.6.32</nowiki>
'''enabled=1'''
gpgcheck=1
<nowiki>gpgkey=http://download.openvz.org/RPM-GPG-Key-OpenVZ</nowiki>
'''#exclude=vzkernel-firmware'''

[openvz-kernel-rhel5]
name=OpenVZ RHEL5-based kernel
<nowiki>#baseurl=http://download.openvz.org/kernel/branches/rhel5-2.6.18/current/</nowiki>
<nowiki>mirrorlist=http://download.openvz.org/kernel/mirrors-rhel5-2.6.18</nowiki>
'''enabled=0'''
gpgcheck=1
<nowiki>gpgkey=http://download.openvz.org/RPM-GPG-Key-OpenVZ</nowiki>

== Install new OpenVZ kernel ==

# yum install vzkernel.x86_64

== Check bootloader configuration ==

Make sure 042stab kernel is there and will boot by default:

cat /boot/grub/grub.conf

timeout 5
default 0
title OpenVZ (2.6.32-042stab081.8)
root (hd0,1)
kernel /vmlinuz-2.6.32-042stab081.8 ro root=/dev/sda3 vga=0x317 selinux=0 sysfs.deprecated=1
initrd /initrd-2.6.32-042stab081.8.img

title OpenVZ (2.6.18-348.16.1.el5.028stab108.1)
root (hd0,1)
kernel /vmlinuz-2.6.18-348.16.1.el5.028stab108.1 ro root=/dev/sda3 vga=0x317 selinux=0
initrd /initrd-2.6.18-348.16.1.el5.028stab108.1.img
....

== Reboot into new kernel ==

# reboot

and make sure the system is up and running.

== Convert /vz to ext4 ==

Boot node from a live-CD (such as, CentOS 6 live CD) and perform the following steps.

Check file system:
# fsck.ext3 -f /dev/sd''xY''

Turn on ext4 features:
# tune2fs -O extents,uninit_bg,dir_index /dev/sd''xY''

Check the new file system again, as ext4 this time:
# fsck.ext4 -fD /dev/sd''xY''

You can do the same for root filesystem, too.

Now, mount your ROOT (<code>/</code>, not <code>/vz</code>) and BOOT partitions:
# mkdir /tmp/root
# mount /dev/sd''aB'' /tmp/root
# mount /dev/sd''aC'' /tmp/root/boot

Finally, chroot into it:
# chroot /tmp/root

Edit its <code>/etc/fstab</code>, replacing <code>ext3</code> with <code>ext4</code> for <code>/vz</code> (and <code>/</code> if you converted it as well).
# vi /etc/fstab

== Create new initrd with proper modules ==

This assumes you are still entered chroot:

# mkinitrd -v -f --with=ext4 --builtin=ehci-hcd --builtin=ohci-hcd --builtin=uhci-hcd \
/boot/initrd-2.6.32-042stab81.8.img 2.6.32-042stab081.8

Notes:
* you have to add ext4 explicitly
* in RHEL6 kernels some USB stuff (that used to be in ehci-hcd, ohci-hcd, uhci-hcd modules) is built-in

== Reboot and enjoy ==

End result is:

# cat /etc/issue
CentOS release 5.10 (Final)
Kernel \r on an \m

# uname -a
Linux CentOS-58-64-minimal 2.6.32-042stab081.8 #1 SMP Mon Sep 30 16:52:24 MSK 2013 x86_64 x86_64 x86_64 GNU/Linux

# df -Th
Filesystem Type Size Used Avail Use% Mounted on
/dev/sda3 ext4 259G 1.5G 244G 1% /
tmpfs tmpfs 16G 0 16G 0% /dev/shm
/dev/sda2 ext3 496M 46M 425M 10% /boot
/dev/sdb1 ext4 1.8T 196M 1.7T 1% /vz

== See also ==

* [[Quick installation]]

== Acknowledgements ==

This article was originally written by [[Denis Hohryakov]].

[[Category: HOWTO]]

@@ Line 76: / Line 76: @@
 == For linux swraid (mdadm) users with bitmap enabled and low IO write speed, you might need to redo bitmap
 cat /proc/mdstat , if chunk size is small  , try (example for internal bitmap) :
-mdadm --grow --bitmap=none /dev/md2
+mdadm --grow --bitmap=none /dev/md2 ;
 mdadm --grow --bitmap=internal --bitmap-chunk=16384 /dev/md2

← Older revision		Revision as of 13:19, 26 May 2015
Line 73:		Line 73:

	and make sure the system is up and running.		and make sure the system is up and running.
		+
		+	== For linux swraid (mdadm) users with bitmap enabled and low IO write speed, you might need to redo bitmap
		+	cat /proc/mdstat , if chunk size is small , try (example for internal bitmap) :
		+	mdadm --grow --bitmap=none /dev/md2
		+	mdadm --grow --bitmap=internal --bitmap-chunk=16384 /dev/md2

	== Convert /vz to ext4 ==		== Convert /vz to ext4 ==

@@ Line 91: / Line 91: @@
 Check the new file system again, as ext4 this time:
-  # fsck.ext4 -fD /dev/sd''xY''
+  # fsck.ext4 -fpD /dev/sd''xY''
 If you have booted from the live CD, you can do the same for root filesystem.

@@ Line 131: / Line 131: @@
 == Acknowledgements ==
-This article was originally written by [[User:Denis Hohryakov]].
+This article was originally written by [[User:Denis Hohryakov|Denis Hohryakov]].
 [[Category: HOWTO]]

@@ Line 109: / Line 109: @@
   # KV=042stab083.2
-  # mkinitrd -v -f --with=ext4 --builtin=ehci-hcd --builtin=ohci-hcd --builtin=uhci-hcd \
+  # mkinitrd -v -f --with=ext4 --without-usb /boot/initrd-2.6.32-${KV}.img 2.6.32-${KV}
 Notes:
 * you have to add ext4 explicitly
-* in RHEL6 kernels some USB stuff (that used to be in ehci-hcd, ohci-hcd, uhci-hcd modules) is built-in
+* in RHEL6 kernels USB modules are built-in
 == Reboot and enjoy ==

@@ Line 1: / Line 1: @@
 This article describes a way to upgrade your old OpenVZ system with RHEL5-based
 (028stabNNN kernel) to RHEL6-based (042stabNNN) kernel, and convert /vz
-from ext3 to ext4.
+from ext3 to ext4, while keeping RHEL/CentOS 5 as a host OS.
 Assumptions:
@@ Line 16: / Line 16: @@
   yum update
 == Add rhel6 kernel repos ==
@@ Line 72: / Line 76: @@
 == Convert /vz to ext4 ==
-Boot node from a live-CD (such as, CentOS 6 live CD) and perform the following steps.
+If your /vz is a separate file system, you need to stop all containers
 Check file system:
@@ Line 78: / Line 88: @@
 Turn on ext4 features:
-  # tune2fs -O extents,uninit_bg,dir_index /dev/sd''xY''
+  # tune4fs -O extents,uninit_bg,dir_index /dev/sd''xY''
 Check the new file system again, as ext4 this time:
   # fsck.ext4 -fD /dev/sd''xY''
-You can do the same for root filesystem, too.
+If you have booted from the live CD, you can do the same for root filesystem.
-Now, mount your ROOT (<code>/</code>, not <code>/vz</code>) and BOOT partitions:
+If you have booted from the live CD, do this:
   # mkdir /tmp/root
   # mount /dev/sd''aB'' /tmp/root
   # mount /dev/sd''aC'' /tmp/root/boot
+* chroot into it:
   # chroot /tmp/root
-Edit its <code>/etc/fstab</code>, replacing <code>ext3</code> with <code>ext4</code> for <code>/vz</code> (and <code>/</code> if you converted it as well).
+Finally, edit <code>/etc/fstab</code>, replacing <code>ext3</code> with <code>ext4</code> for <code>/vz</code> (and <code>/</code> if you converted it as well).
   # vi /etc/fstab
 == Create new initrd with proper modules ==
-This assumes you are still entered chroot:
+ # KV=042stab083.2
   # mkinitrd -v -f --with=ext4 --builtin=ehci-hcd --builtin=ohci-hcd --builtin=uhci-hcd \
-    /boot/initrd-2.6.32-042stab81.8.img 2.6.32-042stab081.8
+    /boot/initrd-2.6.32-${KV}.img 2.6.32-${KV}
 Notes:
@@ Line 124: / Line 133: @@
        /dev/sda2     ext3    496M   46M  425M  10% /boot
        /dev/sdb1     ext4    1.8T  196M  1.7T   1% /vz
 == See also ==