I am having an issue with Megacli when adding or removing virtual disks. I will post a link to fpaste that has the issue shown. In brief whenever i add, or remove, a virtual disk via MegaCli the attempt succeeds and the adapter is configured but the OS remounts dm-0 in read only. dm-0 is my root lv. This issue does not happen if i boot into the default, non Xen, CentOS kernel. On stock CentOS kernel i can add and remove VD's all day without any issue at all. ONLY happens while booted up with the Xen kernel. I have been racking my brain trying to figure this out. Any help is appreciated. My system: Dell Poweredge 2950 II PERC 5/i Controller CentOS 6.7 Xen Version: 4.4.3-1.el6 *Fpaste showing the console log messages during the event:* http://www.fpaste.org/277855/14445392/ *Full XL dump below:* xl info host : cmhinfra1.* release : 3.18.17-13.el6.x86_64 version : #1 SMP Tue Jul 21 17:17:17 UTC 2015 machine : x86_64 nr_cpus : 8 max_cpu_id : 7 nr_nodes : 1 cores_per_socket : 4 threads_per_core : 1 cpu_mhz : 1995 hw_caps : bfebfbff:20100800:00000000:00000900:0004e33d:00000000:00000001:00000000 virt_caps : hvm total_memory : 32762 free_memory : 29340 sharing_freed_memory : 0 sharing_used_memory : 0 outstanding_claims : 0 free_cpus : 0 xen_major : 4 xen_minor : 4 xen_extra : .3-1.el6 xen_version : 4.4.3-1.el6 xen_caps : xen-3.0-x86_64 xen-3.0-x86_32p hvm-3.0-x86_32 hvm-3.0-x86_32p hvm-3.0-x86_64 xen_scheduler : credit xen_pagesize : 4096 platform_params : virt_start=0xffff800000000000 xen_changeset : Thu Apr 23 15:06:13 2015 +0100 git:c5ec076-dirty xen_commandline : dom0_mem=1024M,max:1024M loglvl=all guest_loglvl=all console=tty0 console=com2 com2=57600 cc_compiler : gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-16) cc_compile_by : mockbuild cc_compile_domain : centos.org cc_compile_date : Tue Sep 8 15:31:24 UTC 2015 xend_config_format : 4 *grub.conf:* jeremym]# cat /etc/grub.conf # grub.conf generated by anaconda # # Note that you do not have to rerun grub after making changes to this file # NOTICE: You have a /boot partition. This means that # all kernel and initrd paths are relative to /boot/, eg. # root (hd0,0) # kernel /vmlinuz-version ro root=/dev/mapper/vg_cmhinfra1-lv_root # initrd /initrd-[generic-]version.img #boot=/dev/sdb default=0 timeout=5 #splashimage=(hd0,0)/grub/splash.xpm.gz #hiddenmenu serial --unit=1 --speed=57600 terminal --timeout console serial title CentOS (3.18.17-13.el6.x86_64) root (hd0,0) kernel /xen.gz dom0_mem=1024M,max:1024M loglvl=all guest_loglvl=all console=tty0 console=com2 com2=57600 module /vmlinuz-3.18.17-13.el6.x86_64 ro root=/dev/mapper/vg_cmhinfra1-lv_root rd_LVM_LV=vg_cmhinfra1/lv_swap rd_LVM_LV=vg_cmhinfra1/lv_root console=hvc0 nomodset module /initramfs-3.18.17-13.el6.x86_64.img title CentOS (2.6.32-573.7.1.el6.x86_64) root (hd0,0) kernel /vmlinuz-2.6.32-573.7.1.el6.x86_64 ro root=/dev/mapper/vg_cmhinfra1-lv_root rd_NO_LUKS KEYBOARDTYPE=pc KEYTABLE=us LANG=en_US.UTF-8 rd_NO_MD rd_LVM_LV=vg_cmhinfra1/lv_swap SYSFONT=latarcyrheb-sun16 crashkernel=auto rd_LVM_LV=vg_cmhinfra1/lv_root rd_NO_DM rhgb quiet console=ttyS1,57600 console=tty0 initrd /initramfs-2.6.32-573.7.1.el6.x86_64.img -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.centos.org/pipermail/centos-virt/attachments/20151012/9de7bf0d/attachment-0002.html>