On Tue, 23 Feb 2016 14:40, Francis Greaves wrote: > 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" > To: "Francis Greaves" , "centos-virt" > 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 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" _________________________________________^ If you no not NEED a gfx boot at bare metal, remove the "rhgb" string, this switches grub from a "full graphic" mode to a "hires textmode", AFAICS, this also influences all grub instances in the whole XEN infrastructure, so it could be a influence. >> 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? [snip] - Yamaban.