I discovered after updating and rebooting a centos system that it still shows an old grub menu and the new kernel(s) are not there.
After bootup the links from /etc/grub2.cnf were broken. I recreated these with
grub2-mkconfig -o /boot/efi/EFI/centos/grub.cfg grub2-mkconfig -o /boot/grub2/grub.cfg This fixed the links and I can see the grub config files looks good (in my limited experience, I have not tried to validated the content of the files), but the menu was not updated. In other words on the next reboot I am again presented with a very old boot menu with some anient kernel versions, only one of which is even still on the system.
On further googling I discovered that the /boot/efi partition is a thing and it should be mounted. It is listed in the /etc/fstab file:
# grep efi /etc/fstab UUID=E911-FC5F /boot/efi vfat umask=0077,shortname=winnt,nofail 0 0 I created a directory /mnt/efi and tried to mount it to check the file system but get an error stating that vfat is an unknown file system type
[root@app03 etc]# mount -t vfat /dev/sda1 /mnt/efi mount: unknown filesystem type 'vfat' I even tried with the mount options from the fstab file:
[root@app03 etc]# mount -o umask=0077,shortname=winnt,nofail --verbose /dev/sda1 /mnt/efi mount: unknown filesystem type 'vfat' I tried to load the vfat module but still get the same error
[root@app03 etc]# blkid /dev/sda1 /dev/sda1: SEC_TYPE="msdos" UUID="E911-FC5F" TYPE="vfat" PARTLABEL="EFI System Partition" PARTUUID="895f6027-a800-4f20-8d36-6b5c2f740d90" [root@app03 etc]# lsmod |grep vfat [root@app03 etc]# modprobe vfat [root@app03 etc]# lsmod |grep vfat [root@app03 etc]# locate vfat /usr/lib/modules/3.10.0-1062.18.1.el7.x86_64/kernel/fs/fat/vfat.ko.xz /usr/lib/modules/3.10.0-1160.53.1.el7.x86_64/kernel/fs/fat/vfat.ko.xz /usr/lib/modules/3.10.0-1160.76.1.el7.x86_64/kernel/fs/fat/vfat.ko.xz /usr/lib/modules/3.10.0-1160.88.1.el7.x86_64/kernel/fs/fat/vfat.ko.xz /usr/lib/modules/3.10.0-862.6.3.el7.x86_64/kernel/fs/fat/vfat.ko.xz /usr/sbin/fsck.vfat /usr/sbin/mkfs.vfat /usr/share/man/man8/fsck.vfat.8.gz /usr/share/man/man8/mkfs.vfat.8.gz [root@app03 etc]# mount /dev/sda1 /mnt/efi mount: unknown filesystem type 'vfat' [root@app03 etc]# grep vfat /etc/filesystems vfat [root@app03 etc]# Looking at the partitions doesn't help me much:
[root@app03 etc]# fdisk -l /dev/sda WARNING: fdisk GPT support is currently new, and therefore in an experimental phase. Use at your own discretion. Disk /dev/sda: 479.6 GB, 479559942144 bytes, 936640512 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 262144 bytes / 262144 bytes Disk label type: gpt Disk identifier: BBDE0244-EE22-420F-A32E-DC5CB3CF3540 # Start End Size Type Name 1 2048 411647 200M EFI System EFI System Partition 2 411648 2508799 1G Microsoft basic 3 2508800 936638463 445.4G Linux LVM I'm stuck at this point. I gather I need to re-install the grub using a command such as grub2-install --efi-directory=/boot/efi /dev/sda but as long as /boot/efi is not mounted I fear it will only make matters worse.
In this case /dev/sda1 is the EFI system partition and /dev/sda2 is the /boot partition.
Questions:
- Can I re-create the EFI partition? Is this neccesary? Would it even help at all?
- Can I use the /dev/sda2 partition in stead and install it there?
- I have five of these application servers and the problem exists only on one of them - how could this even happen?
In case it helps, on another server where it works as expected I see the following:
[root@app02 ~]# lsmod |grep vfat vfat 17461 1 fat 65950 1 vfat [root@app02 ~]# mount -v |grep vfat /dev/sda1 on /boot/efi type vfat (rw,relatime,fmask=0077,dmask=0077,codepage=437,iocharset=ascii,shortname=winnt,errors=remount-ro) [root@app02 ~]# df -h |grep efi /dev/sda1 200M 12M 189M 6% /boot/efi 
