So I am planning on upgrading my dom0 from 3.0.4 to 3.1.0. I have already done this for the domU''s. But I need to know my backout plan if something doesn''t go right. I have a simple question. If I install the 3.1.0 from the tarball, can I still boot the 3.0.4 dom0 kernel with the 3.1.0 Xen tools if needed? I''m not sure of the compatibility. I had to compile my own 3.0.4 kernel because of missing SATA drivers in 2.6.16, but I believe they are in 2.6.18, which Xen 3.1.0 is based on. I''ll try and boot the 3.1.0 kernel, but if it fails, can I boot the 3.0.4 kernel even though the xm tools are 3.1.0? Thanks, Greg _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
For what it''s worth, I just did this upgrade recently. I wasn''t prepared to risk breaking my 3.0.4 setup, so I cloned my entire root filesystem (I use an LVM root FS), added an extra grub entry so I could boot from the old or the new one, and only then installed the tarballs in one, keeping the other as a safety net. I had a heck of a time getting my 3.1.0 Dom0 going. It was entirely my own fault, though -- all the problems I had were related to getting the right kernel config parameters for my hardware, and for my initrd setup supporting lvm root filesystem. In hindsight, it would have been trivially easy if I''d just done a diff of my old (2.6.16.33-xen) kernel config versus the stock xen-patched counterpart, and then applied the same changes to the new (2.6.18-xen) kernel. Sorry, I didn''t try running 3.0.4 with the 3.1.0 tools, not 3.1.0 with the 3.0.4 kernel, so I can''t tell you if these permutations work. But I''d bet money that they don''t. Good luck. On 9/25/07, Gregory Gee <gregory.gee@sympatico.ca> wrote:> > > So I am planning on upgrading my dom0 from 3.0.4 to 3.1.0. I have > already done this for the domU''s. But I need to know my backout plan if > something doesn''t go right. I have a simple question. > > If I install the 3.1.0 from the tarball, can I still boot the 3.0.4 > dom0 kernel with the 3.1.0 Xen tools if needed? I''m not sure of the > compatibility. I had to compile my own 3.0.4 kernel because of missing > SATA drivers in 2.6.16, but I believe they are in 2.6.18, which Xen > 3.1.0 is based on. I''ll try and boot the 3.1.0 kernel, but if it > fails, can I boot the 3.0.4 kernel even though the xm tools are 3.1.0? > > Thanks, > Greg > > > _______________________________________________ > Xen-users mailing list > Xen-users@lists.xensource.com > http://lists.xensource.com/xen-users >_______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Gregory Gee wrote:> > So I am planning on upgrading my dom0 from 3.0.4 to 3.1.0. I have > already done this for the domU''s. But I need to know my backout plan > if something doesn''t go right. I have a simple question. > > If I install the 3.1.0 from the tarball, can I still boot the 3.0.4 > dom0 kernel with the 3.1.0 Xen tools if needed?No. You can use kernels build for xen 3.0.3 on 3.1, but the xen userland tools must match xen version.> I''m not sure of the compatibility. I had to compile my own 3.0.4 > kernel because of missing SATA drivers in 2.6.16, but I believe they > are in 2.6.18, which Xen 3.1.0 is based on. I''ll try and boot the > 3.1.0 kernel, but if it fails, can I boot the 3.0.4 kernel even though > the xm tools are 3.1.0? >What distro are you using? On RHEL5 x86_64 : - xen.gz is provided by kernel-xen RPM - xen userland tools is provided by xen RPM, which in turn needs xen-libs For a clean update to xen 3.1, you need to provide kernel-xen, xen, and xen-libs RPM. It also means you can''t have kernel-xen updates from RH automatically used by default (set UPDATEDEFAULT=no in /etc/sysconfig/kernel) since it has xen.gz from xen 3.0.3. Here''s what I did : - create my own xen-3.1.0-0.2.fan.x86_64.rpm, using RH''s Xen-3.0.5 SRPM as a starting point - download RH''s xen-3.0.3-25.0.3.el5.x86_64.rpm xen-libs-3.0.3-25.0.3.el5.x86_64.rpm, for fallback purposes. - yum erase xen-libs.i386 - rpm -Uvh xen-3.1.0-0.2.fan.x86_64.rpm xen-libs-3.1.0-0.2.fan.x86_64.rpm - copy /usr/lib64/xen/xen.gz (created by my xen-3.1 rpm) to /boot/xen.gz-3.1.0-src - create an entry in /boot/grub/menu.lst that looks like this title Xen 3.1 (2.6.18-8.1.10.el5xen) root (hd0,0) kernel /xen.gz-3.1.0-src console=vga module /vmlinuz-2.6.18-8.1.10.el5xen ro root=/dev/rootvg/rootlv quiet xencons=tty module /initrd-2.6.18-8.1.10.el5xen.img note that I just copy an existing kernel-xen section, and change the "kernel" line. - set UPDATEDEFAULT=no in /etc/sysconfig/kernel - reboot Fallback scenario : - rpm -Uvh --oldpackage xen-3.0.3-25.0.3.el5.x86_64.rpm xen-libs-3.0.3-25.0.3.el5.x86_64.rpm - edit /boot/grub/menu.lst to use the original entry Regards, Fajar _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Goswin von Brederlow
2007-Sep-27 06:12 UTC
Re: [Xen-users] Upgrade to 3.1 and backout plan
"Fajar A. Nugraha" <fajar@telkom.net.id> writes:> Gregory Gee wrote: >> >> So I am planning on upgrading my dom0 from 3.0.4 to 3.1.0. I have >> already done this for the domU''s. But I need to know my backout plan >> if something doesn''t go right. I have a simple question.On debian you just install the xen packages. Debian has replaced the tools with wrapper scripts that check the hypervisor version in /sys/ and then start the tools of the right version. Imho the only way to go. I just have multiple entries in grub so I can choose the hypervisor to use. MfG Goswin _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users