Hello all. I''ve been running a Hardy Dom0/DomU for about 2.5 years. Recently I upgraded my test DomU to Karmic because I needed some upgraded tools on my desktop, and wanted to be sure I had an upgrade path that would work. I ran into the /proc/<pid>/mountinfo problem, and had to upgrade the Dom0 to a newer Debian kernel. (If you haven''t been down this path: Karmic requires at least a 2.6.26 kernel because of some /proc updates.) Then I had to upgrade my Dom0 to jaunty to get the Xen 3.3 so Xen could decompress the newer kernels from Karmic. (If you haven''t been down this path, newer linux kernels are sometimes compressed with lzma or bzip2, which Xen 3.2 doesn''t understand.) All seems to be well now -- except that I *cannot* get the console working with my karmic DomU. Today I even used the xen-tools to create a brand spanking new karmic DomU. Everything worked out of the box -- but no console. (There is a practical part of me that says "quit worrying about having a console: embrace your inner ssh". However, I know that eventually my ssh is going to break before a key deadline ...) I''ve tried a million variants of hdc0/xdc0/tty0, and I figure it''s time to actually understand how this thing is supposed to work. So: can someone please explain what needs to be true for a xen DomU console to work? Tons of people are struggling with this problem in all different variants of Xen, but I haven''t yet found a clear, concise outline of the basics of how it should work. The key questions are below. If some xen hero provides answers, I volunteer to write them up for the wiki to restore xen to the world :). Here are the key questions: 1) What is the relationship between xenconsole= and console= in the "extra = " config parameter? 2) Is there a relationship between the Dom0 console and a DomU console? Are there settings that are required on the Dom0 for the DomU console to work? 3) Is the foo in console=foo magic, interpreted by Xen in some mysterious way, or is it just a choice that connects to a normal tty in the domU? 4) Does the DomU need to have a /dev/foo for console=foo to work? If so, what should the properties of /dev/foo be? (I created a /dev/xvc0 on one of my karmic installs, and it got auto-removed on reboot. What''s that all about?!) 5) Does the DomU need to run getty on the /dev/foo? Conversely, is it important that the DomU not run getty? Karmic has changed its way of running getty, which has added to the confusion, but once you find /etc/init it''s pretty easy to follow. 6) Are there key modules that a DomU needs to have in its initrd to have the console work? Has anyone been down this path with karmic before? I''d like to understand the general situation better, but specific advice would be very welcome. Thank you! John _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Hello all. I''ve been running a Hardy Dom0/DomU for about 2.5 years. Recently I upgraded my test DomU to Karmic because I needed some upgraded tools on my desktop, and wanted to be sure I had an upgrade path that would work. I ran into the /proc/<pid>/mountinfo problem, and had to upgrade the Dom0 to a newer Debian kernel. (If you haven''t been down this path: Karmic requires at least a 2.6.26 kernel because of some /proc updates.) Then I had to upgrade my Dom0 to jaunty to get the Xen 3.3 so Xen could decompress the newer kernels from Karmic. (If you haven''t been down this path, newer linux kernels are sometimes compressed with lzma or bzip2, which Xen 3.2 doesn''t understand.) All seems to be well now -- except that I *cannot* get the console working with my karmic DomU. Today I even used the xen-tools to create a brand spanking new karmic DomU. Everything worked out of the box -- but no console. (There is a practical part of me that says "quit worrying about having a console: embrace your inner ssh". However, I know that eventually my ssh is going to break before a key deadline ...) I''ve tried a million variants of hdc0/xdc0/tty0, and I figure it''s time to actually understand how this thing is supposed to work. So: can someone please explain what needs to be true for a xen DomU console to work? Tons of people are struggling with this problem in all different variants of Xen, but I haven''t yet found a clear, concise outline of the basics of how it should work. The key questions are below. If some xen hero provides answers, I volunteer to write them up for the wiki to restore xen to the world :). Here are the key questions: 1) What is the relationship between xenconsole= and console= in the "extra = " config parameter? 2) Is there a relationship between the Dom0 console and a DomU console? Are there settings that are required on the Dom0 for the DomU console to work? 3) Is the foo in console=foo magic, interpreted by Xen in some mysterious way, or is it just a choice that connects to a normal tty in the domU? 4) Does the DomU need to have a /dev/foo for console=foo to work? If so, what should the properties of /dev/foo be? (I created a /dev/xvc0 on one of my karmic installs, and it got auto-removed on reboot. What''s that all about?!) 5) Does the DomU need to run getty on the /dev/foo? Conversely, is it important that the DomU not run getty? Karmic has changed its way of running getty, which has added to the confusion, but once you find /etc/init it''s pretty easy to follow. 6) Are there key modules that a DomU needs to have in its initrd to have the console work? Has anyone been down this path with karmic before? I''d like to understand the general situation better, but specific advice would be very welcome. Thank you! John _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
On Sun, Feb 07, 2010 at 10:01:09AM -0600, John Riedl wrote:> Hello all. I''ve been running a Hardy Dom0/DomU for about 2.5 years. > Recently I upgraded my test DomU to Karmic because I needed some > upgraded tools on my desktop, and wanted to be sure I had an upgrade > path that would work. I ran into the /proc/<pid>/mountinfo problem, > and had to upgrade the Dom0 to a newer Debian kernel. (If you haven''t > been down this path: Karmic requires at least a 2.6.26 kernel because > of some /proc updates.) Then I had to upgrade my Dom0 to jaunty to > get the Xen 3.3 so Xen could decompress the newer kernels from Karmic. > (If you haven''t been down this path, newer linux kernels are > sometimes compressed with lzma or bzip2, which Xen 3.2 doesn''t > understand.) All seems to be well now -- except that I *cannot* get > the console working with my karmic DomU. Today I even used the > xen-tools to create a brand spanking new karmic DomU. Everything > worked out of the box -- but no console. (There is a practical part > of me that says "quit worrying about having a console: embrace your > inner ssh". However, I know that eventually my ssh is going to break > before a key deadline ...) > > I''ve tried a million variants of hdc0/xdc0/tty0,The correct parameters are hvc0 or xvc0.> and I figure it''s > time to actually understand how this thing is supposed to work. So: > can someone please explain what needs to be true for a xen DomU > console to work? Tons of people are struggling with this problem in > all different variants of Xen, but I haven''t yet found a clear, > concise outline of the basics of how it should work. The key > questions are below. If some xen hero provides answers, I volunteer > to write them up for the wiki to restore xen to the world :). Here > are the key questions: > > 1) What is the relationship between xenconsole= and console= in the > "extra = " config parameter? >Older xenlinux kernels use the xencons= parameter, while the newer upstream pv_ops kernels use only the console=.> 2) Is there a relationship between the Dom0 console and a DomU > console? Are there settings that are required on the Dom0 for the > DomU console to work? >No. They''re not related. Only domU configuration affects the domU console.> 3) Is the foo in console=foo magic, interpreted by Xen in some > mysterious way, or is it just a choice that connects to a normal tty > in the domU?No, that information is only handled by the domU kernel.> 4) Does the DomU need to have a /dev/foo for console=foo to work? If > so, what should the properties of /dev/foo be? (I created a /dev/xvc0 > on one of my karmic installs, and it got auto-removed on reboot. > What''s that all about?!)Depends on the domU kernel.> 5) Does the DomU need to run getty on the /dev/foo? Conversely, is it > important that the DomU not run getty? Karmic has changed its way of > running getty, which has added to the confusion, but once you find > /etc/init it''s pretty easy to follow.Yes, it needs to do that.> 6) Are there key modules that a DomU needs to have in its initrd to > have the console work? >Not sure. Console has always worked for me with correct settings :)> Has anyone been down this path with karmic before? I''d like to > understand the general situation better, but specific advice would be > very welcome. >Take a look at this wiki page: http://wiki.xensource.com/xenwiki/XenCommonProblems -- Pasi _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users
Thank you for the reply. Letting me know that getty needed to be running and the pointer to the Common Problems wiki page http://wiki.xensource.com/xenwiki/XenCommonProblems was just the help I needed. Turned out my twin problems were : 1) After trying both xvc0 and hvc0 I was incorrectly concentrating on xvc0 since that''s what was working on my hardy domUs. On the pv_ops kernels, including the recent Ubuntu -server kernels, the correct device is hvc0. /dev/hvc0 exists on my karmic installs. 2) getty does not start on /dev/hvc0 by default on karmic. To start it, just copy /etc/init/tty1.conf to /etc/init/hvc0.conf, and edit appropriately. After that, console works as advertised on both my upgraded karmic, and my new install. Thanks! John _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users