Francis Greaves
2016-Feb-22 16:18 UTC
[CentOS-virt] Garbled screen after RAM Scrub on boot
Dear All I am using Centos 7 with Xen 4.6 on a Dell Poweredge T430 When the machine boots, after the 'Scrubbing Free RAM' message, I get a screen filled with little white squares until the login prompt, so I cannot see what is happening as the machine boots. Also there is nothing on the screen when I reboot. My /etc/default/grub is GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)" GRUB_DEFAULT=saved GRUB_DISABLE_SUBMENU=true GRUB_CMDLINE_LINUX="crashkernel=auto rhgb intremap=no_x2apic_optout" GRUB_CMDLINE_XEN_DEFAULT="dom0_mem=13312M,max:14336M dom0_max_vcpus=6 dom0_vcpus_pin" GRUB_GFXMODE=1024x768 GRUB_GFXPAYLOAD_LINUX=keep GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT="console=hvc0 earlyprintk=xen nomodeset" I have tried setting (for a 1024x768 resolution) vga=792 in the GRUB_CMDLINE_LINUX and commenting out GRUB_GFXMODE and GRUB_GFXPAYLOAD_LINUX, but this makes no difference What am I doing wrong? Regards Francis -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos-virt/attachments/20160222/6ab6dc20/attachment-0002.html>
When I was running Fedora 23 and using Xen (as the host OS), I saw something similar on my Dell Precision 470. I don't recall seeing it now with CentOS 7, but I tend to boot that machine headless more than not... On Mon, 22 Feb 2016, Francis Greaves wrote:> Dear All > I am using Centos 7 with Xen 4.6 on a Dell Poweredge T430 > When the machine boots, after the 'Scrubbing Free RAM' message, I get a screen filled with little white squares until the login prompt, so I cannot see > what is happening as the machine boots. Also there is nothing on the screen when I reboot. > > My /etc/default/grub is > > GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)" > GRUB_DEFAULT=saved > GRUB_DISABLE_SUBMENU=true > GRUB_CMDLINE_LINUX="crashkernel=auto rhgb intremap=no_x2apic_optout" > GRUB_CMDLINE_XEN_DEFAULT="dom0_mem=13312M,max:14336M dom0_max_vcpus=6 dom0_vcpus_pin" > GRUB_GFXMODE=1024x768 > GRUB_GFXPAYLOAD_LINUX=keep > GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT="console=hvc0 earlyprintk=xen nomodeset" > > I have tried setting (for a 1024x768 resolution) vga=792 in the GRUB_CMDLINE_LINUX and commenting out GRUB_GFXMODE and GRUB_GFXPAYLOAD_LINUX, but this > makes no difference > > What am I doing wrong? > > Regards > Francis > >Scot P. Floess RHCT (Certificate Number 605010084735240) Chief Architect FlossWare http://sourceforge.net/projects/flossware http://flossware.sourceforge.net https://github.com/organizations/FlossWare
Francis Greaves
2016-Feb-22 17:51 UTC
[CentOS-virt] Garbled screen after RAM Scrub on boot
Yes I usually work headless, but I have been setting it up from new, so need to see what is going on. Regards Francis From: "Scot P. Floess" <sfloess at nc.rr.com> To: "Francis Greaves" <francis at choughs.net> Cc: "centos-virt" <centos-virt at centos.org> Sent: Monday, 22 February, 2016 17:02:12 Subject: Re: [CentOS-virt] Garbled screen after RAM Scrub on boot When I was running Fedora 23 and using Xen (as the host OS), I saw something similar on my Dell Precision 470. I don't recall seeing it now with CentOS 7, but I tend to boot that machine headless more than not... On Mon, 22 Feb 2016, Francis Greaves wrote:> Dear All > I am using Centos 7 with Xen 4.6 on a Dell Poweredge T430 > When the machine boots, after the 'Scrubbing Free RAM' message, I get a screen filled with little white squares until the login prompt, so I cannot see > what is happening as the machine boots. Also there is nothing on the screen when I reboot. > > My /etc/default/grub is > > GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)" > GRUB_DEFAULT=saved > GRUB_DISABLE_SUBMENU=true > GRUB_CMDLINE_LINUX="crashkernel=auto rhgb intremap=no_x2apic_optout" > GRUB_CMDLINE_XEN_DEFAULT="dom0_mem=13312M,max:14336M dom0_max_vcpus=6 dom0_vcpus_pin" > GRUB_GFXMODE=1024x768 > GRUB_GFXPAYLOAD_LINUX=keep > GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT="console=hvc0 earlyprintk=xen nomodeset" > > I have tried setting (for a 1024x768 resolution) vga=792 in the GRUB_CMDLINE_LINUX and commenting out GRUB_GFXMODE and GRUB_GFXPAYLOAD_LINUX, but this > makes no difference > > What am I doing wrong? > > Regards > Francis > >Scot P. Floess RHCT (Certificate Number 605010084735240) Chief Architect FlossWare http://sourceforge.net/projects/flossware http://flossware.sourceforge.net https://github.com/organizations/FlossWare -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos-virt/attachments/20160222/832003fb/attachment-0002.html>
On Mon, Feb 22, 2016 at 4:18 PM, Francis Greaves <francis at choughs.net> wrote:> Dear All > I am using Centos 7 with Xen 4.6 on a Dell Poweredge T430 > When the machine boots, after the 'Scrubbing Free RAM' message, I get a > screen filled with little white squares until the login prompt, so I cannot > see what is happening as the machine boots. Also there is nothing on the > screen when I reboot. > > My /etc/default/grub is > > GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)" > GRUB_DEFAULT=saved > GRUB_DISABLE_SUBMENU=true > GRUB_CMDLINE_LINUX="crashkernel=auto rhgb intremap=no_x2apic_optout" > GRUB_CMDLINE_XEN_DEFAULT="dom0_mem=13312M,max:14336M dom0_max_vcpus=6 > dom0_vcpus_pin" > GRUB_GFXMODE=1024x768 > GRUB_GFXPAYLOAD_LINUX=keep > GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT="console=hvc0 earlyprintk=xen > nomodeset" > > I have tried setting (for a 1024x768 resolution) vga=792 in the > GRUB_CMDLINE_LINUX and commenting out GRUB_GFXMODE and > GRUB_GFXPAYLOAD_LINUX, but this makes no difference > > What am I doing wrong?Francis, Thanks for reporting this. I'd suggest re-posting your question on xen-users -- there are a lot more eyeballs watching that list than this one, and it's easier to "escalate" the issue to the development list from there. My first instinct is wondering whether grub setting the graphics mode is part of the problem. Have you tried having grub just take the bios text mode that was given it, rather than changing it? (Obviously ideally Xen would work whatever the graphics mode is, but most developers are accessing test boxes over serial in a colo, so it's not the kind of thing they're prone to notice.) -George
Francis Greaves
2016-Feb-23 13:40 UTC
[CentOS-virt] Garbled screen after RAM Scrub on boot
Dear George, Thanks for the input and ideas. Unfortunately bootscrub=false dos not work, not does setting nothing for vga, still get the 'Little white squares'! I am asking the xen-users as you suggest Regards, Francis From: "George Dunlap" <dunlapg at umich.edu> To: "Francis Greaves" <francis at choughs.net>, "centos-virt" <centos-virt at centos.org> Sent: Tuesday, 23 February, 2016 09:31:40 Subject: Re: [CentOS-virt] Garbled screen after RAM Scrub on boot On Mon, Feb 22, 2016 at 4:18 PM, Francis Greaves <francis at choughs.net> wrote:> Dear All > I am using Centos 7 with Xen 4.6 on a Dell Poweredge T430 > When the machine boots, after the 'Scrubbing Free RAM' message, I get a > screen filled with little white squares until the login prompt, so I cannot > see what is happening as the machine boots. Also there is nothing on the > screen when I reboot. > > My /etc/default/grub is > > GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)" > GRUB_DEFAULT=saved > GRUB_DISABLE_SUBMENU=true > GRUB_CMDLINE_LINUX="crashkernel=auto rhgb intremap=no_x2apic_optout" > GRUB_CMDLINE_XEN_DEFAULT="dom0_mem=13312M,max:14336M dom0_max_vcpus=6 > dom0_vcpus_pin" > GRUB_GFXMODE=1024x768 > GRUB_GFXPAYLOAD_LINUX=keep > GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT="console=hvc0 earlyprintk=xen > nomodeset" > > I have tried setting (for a 1024x768 resolution) vga=792 in the > GRUB_CMDLINE_LINUX and commenting out GRUB_GFXMODE and > GRUB_GFXPAYLOAD_LINUX, but this makes no difference > > What am I doing wrong?Francis, Thanks for reporting this. I'd suggest re-posting your question on xen-users -- there are a lot more eyeballs watching that list than this one, and it's easier to "escalate" the issue to the development list from there. My first instinct is wondering whether grub setting the graphics mode is part of the problem. Have you tried having grub just take the bios text mode that was given it, rather than changing it? (Obviously ideally Xen would work whatever the graphics mode is, but most developers are accessing test boxes over serial in a colo, so it's not the kind of thing they're prone to notice.) -George -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos-virt/attachments/20160223/45b075a2/attachment-0002.html>