Sysadmin Grub Help?

rdan · Dec 8, 2018

eva2000 said: ↑

Interesting that it is still a problem for your setup - is it the exact same server too ?
Click to expand...

Different server with same specs.
First reboot since August 2017.

eva2000 · Dec 8, 2018

Ah I see

rdan · Jan 21, 2019

Jimmy said: ↑

Where md/md2 is the drive with your OS.
Click to expand...

Do you guys have any idea about this?

Grub is missing :/

rdan · Jan 21, 2019

Will it be fix by copying all files from
/usr/lib/grub/x86_64-efi/ to
/boot/grub2 ?

But I can't CP though on grub console.

rdan · Jan 21, 2019

I boot on rescue mode, then mounted
mount /dev/md3 to /mnt/
I can now copy files on this console?

/mnt/usr/lib/grub/x86_64-efi/
to
/mnt/boot/grub2 ?

rdan · Jan 21, 2019

rdan said: ↑

I boot on rescue mode, then mounted
mount /dev/md3 to /mnt/
I can now copy files on this console?

/mnt/usr/lib/grub/x86_64-efi/
to
/mnt/boot/grub2 ?
Click to expand...

Done this, I did successfully executed this command:

grub> set prefix=(md/md2)/boot/grub2
grub> set root=(md/md2)
grub> insmod linux
grub> normal
Click to expand...

But still after reboot, stuck on grub console.

Not sure what else I need to do :/

rdan · Jan 21, 2019

root@rescue:~# sudo mount /dev/md3 /mnt
root@rescue:~# sudo grub-install --boot-directory=/mnt /dev/md
md/ md2 md3
root@rescue:~# sudo grub-install --boot-directory=/mnt /dev/md3
Installing for x86_64-efi platform.
grub-install: error: cannot find EFI directory.

pamamolf · Jan 21, 2019

From grub run:
Code:
ls
you will see something like this:

(md/md3) (md/md2) (hd0)

then run:
Code:
ls (md/md2)
or
ls (md/md2)/
just to veryify that md2 is the main disk by finding the folder /home

If md2 is the main disk then run:
Code:
set prefix=(md/md2)/boot/grub2
set root=(md/md2)
insmod linux
normal
reboot the server after that

Then it should boot...

And then run:
Code:
yum reinstall grub2-efi shim
grub2-mkconfig -o /boot/efi/EFI/centos/grub.cfg
reboot

rdan · Jan 21, 2019

pamamolf said: ↑
From grub run:
Code:
ls
you will see something like this:

(md/md3) (md/md2) (hd0)

then run:
Code:
ls (md/md2)
or
ls (md/md2)/
just to veryify that md2 is the main disk by finding the folder /home

If md2 is the main disk then run:
Code:
set prefix=(md/md2)/boot/grub2
set root=(md/md2)
insmod linux
normal
reboot the server after that

Then it should boot...

And then run:
Code:
yum reinstall grub2-efi shim
grub2-mkconfig -o /boot/efi/EFI/centos/grub.cfg
reboot
Click to expand...
That is not working with me.
For some reason /boot/ is empty :/

eva2000 · Sep 15, 2019

I am testing 3 dedicated servers with 1.2TB NVMe SSD on CentOS 7 and looking at additional checks for this potential grub issue. So can folks who are using NVMe ssd based centos 7 servers run these commands on the NVMe based servers and post the output you get
Code (Text):
yum -q -y install efibootmgr
efibootmgr
ls -lah /boot/efi/EFI/centos
ls -lah /sys/firmware/efi
dmesg | grep -i efi
egrep 'linux16|initrd16|linuxefi|initrdefi' /boot/grub2/grub.cfg
egrep 'linux16|initrd16|linuxefi|initrdefi' /boot/efi/EFI/centos/grub.cfg
df -hT
mention the web host the server is with too

Matt · Sep 15, 2019

Code:

[17:40][root@*]# efibootmgr
BootCurrent: 0003
Timeout: 0 seconds
BootOrder: 0003,0009,0008,0006,0004,0005,0007,0000,0001,0002
Boot0000* Enter Setup
Boot0001  Boot Device List
Boot0002  Network Boot
Boot0003* UEFI IPv4: Intel I210 Network 00 at Baseboard
Boot0004* UEFI IPv6: Intel I210 Network 00 at Baseboard
Boot0005* Launch EFI Shell
Boot0006* UEFI IPv4: Intel I210 Network 00 at Baseboard 2
Boot0007* UEFI IPv6: Intel I210 Network 00 at Baseboard 2
Boot0008* centos
Boot0009* centos7_64 (GRUB) (first drive nvme0n1)
Boot000A* UEFI Misc Device
[17:41][root@*]# ls -lah /boot/efi/EFI/centos
total 152K
drwxr-xr-x. 3 root root 4.0K Jun  5 06:30 .
drwxr-xr-x. 3 root root 4.0K Jun  5 06:30 ..
drwxr-xr-x. 2 root root 4.0K Jun  5 06:30 fonts
-rwxr-xr-x. 1 root root 1.0K Aug  2 10:37 grubenv
-rwxr-xr-x. 1 root root 136K Jun  5 06:30 grubx64.efi
[17:41][root@*]# ls -lah /sys/firmware/efi
total 0
drwxr-xr-x.  5 root root    0 Sep 14 17:39 .
drwxr-xr-x.  7 root root    0 Sep 14 17:39 ..
-r--r--r--.  1 root root 4.0K Sep 14 17:39 config_table
drwxr-xr-x.  2 root root    0 Jun  5 08:13 efivars
-r--r--r--.  1 root root 4.0K Sep 14 17:39 fw_platform_size
-r--r--r--.  1 root root 4.0K Sep 14 17:39 fw_vendor
-r--r--r--.  1 root root 4.0K Sep 14 17:39 runtime
drwxr-xr-x.  8 root root    0 Sep 14 17:39 runtime-map
-r--------.  1 root root 4.0K Sep 14 17:39 systab
drwxr-xr-x. 90 root root    0 Sep 14 17:39 vars
[17:41][root@*]# dmesg | grep -i efi
[17:41][root@*]# df -hT
Filesystem     Type      Size  Used Avail Use% Mounted on
/dev/md2       ext4      411G  181G  209G  47% /
devtmpfs       devtmpfs   16G     0   16G   0% /dev
tmpfs          tmpfs      16G     0   16G   0% /dev/shm
tmpfs          tmpfs      16G  1.6G   14G  11% /run
tmpfs          tmpfs      16G     0   16G   0% /sys/fs/cgroup
/dev/nvme0n1p1 vfat      510M  2.7M  508M   1% /boot/efi
tmpfs          tmpfs     3.1G     0  3.1G   0% /run/user/0

Code:

[18:42][root@*]# efibootmgr
BootCurrent: 0003
Timeout: 1 seconds
BootOrder: 0003,0004,0005,0006,0008,0007
Boot0002  UEFI: Built-in EFI Shell
Boot0003* UEFI: PXE IP4 Intel(R) Ethernet Controller X540-AT2
Boot0004* UEFI: PXE IP4 Intel(R) Ethernet Controller X540-AT2
Boot0005* UEFI: PXE IP4 Broadcom NetXtreme Gigabit Ethernet (BCM5720)
Boot0006* UEFI: PXE IP4 Broadcom NetXtreme Gigabit Ethernet (BCM5720)
Boot0007  USB
Boot0008  UEFI: Built-in EFI Shell
[18:42][root@*]# ls -lah /boot/efi/EFI/centos
total 144K
drwxr-xr-x. 2 root root 4.0K Jul  6 07:26 .
drwxr-xr-x. 3 root root 4.0K Jul  6 07:26 ..
-rwxr-xr-x. 1 root root 136K Jul  6 07:26 grubx64.efi
[18:42][root@*]# ls -lah /sys/firmware/efi
total 0
drwxr-xr-x.  6 root root    0 Sep 14 18:42 .
drwxr-xr-x.  7 root root    0 Jul  6 07:32 ..
-r--r--r--.  1 root root 4.0K Sep 14 18:42 config_table
drwxr-xr-x.  2 root root    0 Jul  6 07:32 efivars
drwxr-xr-x.  3 root root    0 Sep 14 18:42 esrt
-r--r--r--.  1 root root 4.0K Sep 14 18:42 fw_platform_size
-r--r--r--.  1 root root 4.0K Sep 14 18:42 fw_vendor
-r--r--r--.  1 root root 4.0K Sep 14 18:42 runtime
drwxr-xr-x. 25 root root    0 Sep 14 18:42 runtime-map
-r--------.  1 root root 4.0K Jul  6 07:33 systab
drwxr-xr-x. 76 root root    0 Sep 14 18:42 vars
[18:42][root@*]# dmesg | grep -i efi
[18:42][root@*]# df -hT
Filesystem     Type      Size  Used Avail Use% Mounted on
/dev/md2       ext4      1.8T  507G  1.2T  31% /
devtmpfs       devtmpfs   63G     0   63G   0% /dev
tmpfs          tmpfs      63G   20M   63G   1% /dev/shm
tmpfs          tmpfs      63G  4.1G   59G   7% /run
tmpfs          tmpfs      63G     0   63G   0% /sys/fs/cgroup
/dev/nvme0n1p1 vfat      510M  152K  510M   1% /boot/efi
tmpfs          tmpfs      13G     0   13G   0% /run/user/0

Both OVH, and haven't been rebooted since they were initially spun up (running kernel care, so only rebooting as a last resort with them).

Just checked, and both had broken /etc/grub2-efi.cfg symlinks, as /boot/efi/EFI/centos/grub.cfg was missing until running the following command

Code:

[18:49][root@*]# grub2-mkconfig -o /boot/efi/EFI/centos/grub.cfg
Generating grub configuration file ...
Found linux image: /boot/vmlinuz-3.10.0-957.27.2.el7.x86_64
Found initrd image: /boot/initramfs-3.10.0-957.27.2.el7.x86_64.img
Found linux image: /boot/vmlinuz-3.10.0-957.21.3.el7.x86_64
Found initrd image: /boot/initramfs-3.10.0-957.21.3.el7.x86_64.img
Found linux image: /boot/vmlinuz-0-rescue-6ab4ad267a0360ab401378365d203d99
Found initrd image: /boot/initramfs-0-rescue-6ab4ad267a0360ab401378365d203d99.img
done

Matt · Sep 15, 2019

Checked my 3rd server with them that has NVMe and it was the same.

eva2000 · Sep 15, 2019

Matt said: ↑

Both OVH, and haven't been rebooted since they were initially spun up (running kernel care, so only rebooting as a last resort with them).

Just checked, and both had broken /etc/grub2-efi.cfg symlinks, as /boot/efi/EFI/centos/grub.cfg was missing until running the following command
Click to expand...

Cheers @Matt interesting trying to determine if a server is booting with UEFI or non-UEFI bios as usually googled tests don't seem to apply to ALL checks from what you posted heh.

What's output for these 2 commands as well
Code (Text):
egrep 'linux16|initrd16|linuxefi|initrdefi' /boot/grub2/grub.cfg
egrep 'linux16|initrd16|linuxefi|initrdefi' /boot/efi/EFI/centos/grub.cfg

Matt · Sep 15, 2019

However, looking at the verbose output of efibootmgr

Code:

18:02][root@*]# efibootmgr -v
BootCurrent: 0003
Timeout: 0 seconds
BootOrder: 0003,0009,0008,0006,0004,0005,0007,0000,0001,0002
Boot0000* Enter Setup    FvVol(cdbb7b35-6833-4ed6-9ab2-57d2acddf6f0)/FvFile(462caa21-7614-4503-836e-8ab6f4662331)
Boot0001  Boot Device List    FvVol(cdbb7b35-6833-4ed6-9ab2-57d2acddf6f0)/FvFile(eec25bdc-67f2-4d95-b1d5-f81b2039d11d)$.I.B.T...
Boot0002  Network Boot    FvVol(cdbb7b35-6833-4ed6-9ab2-57d2acddf6f0)/FvFile(9e09e6fd-4e16-6468-9b78-bdaeaf609cff)$.I.B.T...
Boot0003* UEFI IPv4: Intel I210 Network 00 at Baseboard    /Pci(0x1d,0x2)/Pci(0x0,0x0)/MAC(a4bf012063f2,0)/IPv4(0.0.0.00.0.0.0,0,0)N.....YM....R,Y.
Boot0004* UEFI IPv6: Intel I210 Network 00 at Baseboard    /Pci(0x1d,0x3)/Pci(0x0,0x0)/MAC(a4bf012063f3,0)/IPv6([::]:<->[::]:,0,0)N.....YM....R,Y.
Boot0005* Launch EFI Shell    FvVol(cdbb7b35-6833-4ed6-9ab2-57d2acddf6f0)/FvFile(c57ad6b7-0515-40a8-9d21-551652854e37)
Boot0006* UEFI IPv4: Intel I210 Network 00 at Baseboard 2    /Pci(0x1d,0x3)/Pci(0x0,0x0)/MAC(a4bf012063f3,0)/IPv4(0.0.0.00.0.0.0,0,0)N.....YM....R,Y.
Boot0007* UEFI IPv6: Intel I210 Network 00 at Baseboard 2    /Pci(0x1d,0x2)/Pci(0x0,0x0)/MAC(a4bf012063f2,0)/IPv6([::]:<->[::]:,0,0)N.....YM....R,Y.
Boot0008* centos    HD(1,GPT,050ee7d4-35c8-453b-98be-dc1136ec1b7d,0x800,0xff800)/File(\EFI\centos\grubx64.efi)
Boot0009* centos7_64 (GRUB) (first drive nvme0n1)    HD(1,GPT,050ee7d4-35c8-453b-98be-dc1136ec1b7d,0x800,0xff800)/File(\EFI\centos\grubx64.efi)
Boot000A* UEFI Misc Device    /Pci(0x1,0x1)/Pci(0x0,0x0)/NVMe(0x1,00-00-00-00-00-00-00-00)N.....YM....R,Y.

It's booting from the 3rd entrty which is the NIC (booting in the standard OS kernel on the drives, not the OVH custom kernel)

Matt · Sep 15, 2019

Code:

[18:02][root@*]# egrep 'linux16|initrd16|linuxefi|initrdefi' /boot/grub2/grub.cfg
    linuxefi /boot/vmlinuz-3.10.0-957.27.2.el7.x86_64 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0 LANG=en_US.UTF-8
    initrdefi /boot/initramfs-3.10.0-957.27.2.el7.x86_64.img
    linuxefi /boot/vmlinuz-3.10.0-957.12.2.el7.x86_64 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0
    initrdefi /boot/initramfs-3.10.0-957.12.2.el7.x86_64.img
    linuxefi /boot/vmlinuz-0-rescue-9139efd81b40e4f54a7681b55cf760f7 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0
    initrdefi /boot/initramfs-0-rescue-9139efd81b40e4f54a7681b55cf760f7.img
[18:04][root@*]# egrep 'linux16|initrd16|linuxefi|initrdefi' /boot/efi/EFI/centos/grub.cfg
    linuxefi /boot/vmlinuz-3.10.0-957.27.2.el7.x86_64 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0
    initrdefi /boot/initramfs-3.10.0-957.27.2.el7.x86_64.img
    linuxefi /boot/vmlinuz-3.10.0-957.12.2.el7.x86_64 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0
    initrdefi /boot/initramfs-3.10.0-957.12.2.el7.x86_64.img
    linuxefi /boot/vmlinuz-0-rescue-9139efd81b40e4f54a7681b55cf760f7 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0
    initrdefi /boot/initramfs-0-rescue-9139efd81b40e4f54a7681b55cf760f7.img

eva2000 · Sep 15, 2019

Matt said: ↑

BootOrder: 0003,0009,0008,0006,0004,0005,0007,0000,0001,0002
Click to expand...

or is boot order for 0003 then 0009

Boot0009* centos7_64 (GRUB) (first drive nvme0n1)

then

Boot0008* centos HD

Matt · Sep 15, 2019

Yeah, but look at bootcurrent

Code:

18:02][root@*]# efibootmgr -v
BootCurrent: 0003
Timeout: 0 seconds
BootOrder: 0003,0009,0008,0006,0004,0005,0007,0000,0001,0002

Matt · Sep 15, 2019

another OVH server a customer has which has never been rebooted

Code:

[root@host ~]# efibootmgr
ls -lah /boot/efi/EFI/centos
BootCurrent: 0003
Timeout: 0 seconds
BootOrder: 0003,000B,0009,0006,0004,0005,0007,0000,0001,0002
Boot0000* Enter Setup
Boot0001  Boot Device List
Boot0002  Network Boot
Boot0003* UEFI IPv4: Intel I210 Network 00 at Baseboard
Boot0004* UEFI IPv6: Intel I210 Network 00 at Baseboard
Boot0005* Launch EFI Shell
Boot0006* UEFI IPv4: Intel I210 Network 00 at Baseboard 2
Boot0007* UEFI IPv6: Intel I210 Network 00 at Baseboard 2
Boot0008* UEFI Misc Device
Boot0009* centos
Boot000A* UEFI Misc Device 2
Boot000B* centos7_64 (GRUB) (first drive nvme0n1)
[root@host ~]# ls -lah /boot/efi/EFI/centos
total 156K
drwxr-xr-x. 3 root root 4.0K Feb 10  2019 .
drwxr-xr-x. 3 root root 4.0K Feb 18  2019 ..
drwxr-xr-x. 2 root root 4.0K Feb 10  2019 fonts
-rwxr-xr-x. 1 root root 1.0K Aug 11 03:46 grubenv
-rwxr-xr-x. 1 root root 138K Feb 10  2019 grubx64.efi
[root@host ~]# ls -lah /sys/firmware/efi
total 0
drwxr-xr-x.  5 root root    0 Sep 14 14:17 .
drwxr-xr-x.  7 root root    0 Feb 10  2019 ..
-r--r--r--.  1 root root 4.0K Feb 10  2019 config_table
drwxr-xr-x.  2 root root    0 Feb 10  2019 efivars
-r--r--r--.  1 root root 4.0K Sep 14 14:17 fw_platform_size
-r--r--r--.  1 root root 4.0K Feb 10  2019 fw_vendor
-r--r--r--.  1 root root 4.0K Feb 10  2019 runtime
drwxr-xr-x.  8 root root    0 Feb 10  2019 runtime-map
-r--------.  1 root root 4.0K Feb 10  2019 systab
drwxr-xr-x. 92 root root    0 Sep 14 14:17 vars
[root@host ~]# dmsg | grep -i efi
-bash: dmsg: command not found
[root@host ~]# egrep 'linux16|initrd16|linuxefi|initrdefi' /boot/grub2/grub.cfg
        linuxefi /boot/vmlinuz-3.10.0-957.27.2.el7.x86_64 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=7f6baae9:f01f6156:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 rootflags=uquota noquiet nosplash net.ifnames=0 biosdevname=0 LANG=en_US.UTF-8
        initrdefi /boot/initramfs-3.10.0-957.27.2.el7.x86_64.img
        linuxefi /boot/vmlinuz-3.10.0-957.5.1.el7.x86_64 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=7f6baae9:f01f6156:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 rootflags=uquota noquiet nosplash net.ifnames=0 biosdevname=0
        initrdefi /boot/initramfs-3.10.0-957.5.1.el7.x86_64.img
        linuxefi /boot/vmlinuz-0-rescue-ccd3ffab29f1fab8bed3c8f85c602916 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=7f6baae9:f01f6156:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 rootflags=uquota noquiet nosplash net.ifnames=0 biosdevname=0
        initrdefi /boot/initramfs-0-rescue-ccd3ffab29f1fab8bed3c8f85c602916.img
[root@host ~]# egrep 'linux16|initrd16|linuxefi|initrdefi' /boot/efi/EFI/centos/grub.cfg
grep: /boot/efi/EFI/centos/grub.cfg: No such file or directory
[root@host ~]# df -hT
Filesystem     Type      Size  Used Avail Use% Mounted on
/dev/md2       xfs       417G   56G  361G  14% /
devtmpfs       devtmpfs   32G     0   32G   0% /dev
tmpfs          tmpfs      32G   12K   32G   1% /dev/shm
tmpfs          tmpfs      32G  3.2G   29G  10% /run
tmpfs          tmpfs      32G     0   32G   0% /sys/fs/cgroup
/dev/nvme0n1p1 vfat      510M  2.7M  508M   1% /boot/efi
/dev/loop0     ext3      3.9G  8.6M  3.7G   1% /tmp
tmpfs          tmpfs     6.3G     0  6.3G   0% /run/user/0

eva2000 · Sep 15, 2019

ah yes wonder if that is so OVH network recovery disk can work ?

Matt said: ↑

Code:

[18:02][root@*]# egrep 'linux16|initrd16|linuxefi|initrdefi' /boot/grub2/grub.cfg
    linuxefi /boot/vmlinuz-3.10.0-957.27.2.el7.x86_64 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0 LANG=en_US.UTF-8
    initrdefi /boot/initramfs-3.10.0-957.27.2.el7.x86_64.img
    linuxefi /boot/vmlinuz-3.10.0-957.12.2.el7.x86_64 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0
    initrdefi /boot/initramfs-3.10.0-957.12.2.el7.x86_64.img
    linuxefi /boot/vmlinuz-0-rescue-9139efd81b40e4f54a7681b55cf760f7 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0
    initrdefi /boot/initramfs-0-rescue-9139efd81b40e4f54a7681b55cf760f7.img
[18:04][root@*]# egrep 'linux16|initrd16|linuxefi|initrdefi' /boot/efi/EFI/centos/grub.cfg
    linuxefi /boot/vmlinuz-3.10.0-957.27.2.el7.x86_64 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0
    initrdefi /boot/initramfs-3.10.0-957.27.2.el7.x86_64.img
    linuxefi /boot/vmlinuz-3.10.0-957.12.2.el7.x86_64 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0
    initrdefi /boot/initramfs-3.10.0-957.12.2.el7.x86_64.img
    linuxefi /boot/vmlinuz-0-rescue-9139efd81b40e4f54a7681b55cf760f7 root=/dev/md2 ro crashkernel=auto rhgb quiet vga=normal nomodeset rd.auto=1 rd.md.uuid=0239b761:92ee10a0:a4d2adc2:26fd5302 rootdelay=10 rootdelay=10 noquiet nosplash net.ifnames=0 biosdevname=0
    initrdefi /boot/initramfs-0-rescue-9139efd81b40e4f54a7681b55cf760f7.img

Click to expand...

thanks Matt, sort of confirms how I can check if server is booting from UEFI bios or not

1. grub.cf entries load /boot/vmlinuz via linuxefi instead of linux16 and load /boot/initramfs using initrdefi instead of initrd16

2. efibootmgr returns info instead of

Code (Text):

efibootmgr
EFI variables are not supported on this system.

3. directory for /sys/firmware/efi exists

4. nvme labaled mount goes to /boot/efi (UEFI) instead of /boot (non-UEFI)

your output shows /boot/efi

Code (Text):

df -hT
Filesystem     Type      Size  Used Avail Use% Mounted on
/dev/md2       ext4      1.8T  507G  1.2T  31% /
devtmpfs       devtmpfs   63G     0   63G   0% /dev
tmpfs          tmpfs      63G   20M   63G   1% /dev/shm
tmpfs          tmpfs      63G  4.1G   59G   7% /run
tmpfs          tmpfs      63G     0   63G   0% /sys/fs/cgroup
/dev/nvme0n1p1 vfat      510M  152K  510M   1% /boot/efi
tmpfs          tmpfs      13G     0   13G   0% /run/user/0

on my 1.2TB NVMe servers it shows mount is /boot and not /boot/efi and grub shows loading via linux16 instead of linuxefi and /sys/firmware/efi doesn't exist on my servers so suggests non-UEFI bios

Code (Text):

df -hT
Filesystem     Type      Size  Used Avail Use% Mounted on
/dev/nvme0n1p2 ext4      1.1T  1.3G  1.1T   1% /
devtmpfs       devtmpfs   16G     0   16G   0% /dev
tmpfs          tmpfs      16G     0   16G   0% /dev/shm
tmpfs          tmpfs      16G  8.9M   16G   1% /run
tmpfs          tmpfs      16G     0   16G   0% /sys/fs/cgroup
/dev/nvme0n1p1 ext4      976M  149M  761M  17% /boot
tmpfs          tmpfs     3.2G     0  3.2G   0% /run/user/0

Code (Text):

egrep 'linux16|initrd16|linuxefi|initrdefi' /boot/grub2/grub.cfg
        linux16 /vmlinuz-3.10.0-957.27.2.el7.x86_64 root=UUID=b069c64f-8c96-436a-92ed-367ca3ff21b7 ro crashkernel=auto rhgb quiet LANG=en_US.UTF-8
        initrd16 /initramfs-3.10.0-957.27.2.el7.x86_64.img
        linux16 /vmlinuz-3.10.0-957.el7.x86_64 root=UUID=b069c64f-8c96-436a-92ed-367ca3ff21b7 ro crashkernel=auto rhgb quiet LANG=en_US.UTF-8
        initrd16 /initramfs-3.10.0-957.el7.x86_64.img
        linux16 /vmlinuz-0-rescue-0cc0bdde29a447c29dd1c7eff80c1b40 root=UUID=b069c64f-8c96-436a-92ed-367ca3ff21b7 ro crashkernel=auto rhgb quiet
        initrd16 /initramfs-0-rescue-0cc0bdde29a447c29dd1c7eff80c1b40.img

blank on supposed non-UEFI bios so legacy bios

Code (Text):

ls -lah /boot/efi/EFI/centos/                                       
total 8.0K
drwx------. 2 root root 4.0K Jan 30  2019 .
drwxr-xr-x. 3 root root 4.0K Sep 13 12:21 ..

so in theory my 1.2TB NVMe server is not booting via UEFI bios and using legacy bios and shoud NOT need to do extra command (grub2-mkconfig -o /boot/efi/EFI/centos/grub.cfg) to regenerate grub.cfg on bios updates like the servers from OVH mentioned in this thread

Matt · Sep 15, 2019

eva2000 · Sep 15, 2019

Matt said: ↑

View attachment 6916
Click to expand...

yeah missing grub2-efi.cfg on your OVH servers which suggest high likelihood you'd run into this thread's original issue of reboot not working if you have OVH CentOS 7 OS image and updating linux kernel + reboot of server as OVH server's use UEFI bios and NVMe mounted /boot/efi partition so looking for /boot/efi/EFI/centos/grub.cfg instead of normal /boot/grub2/grub.cfg

Log in / Register

Forums

Want to subscribe to topics you're interested in?

Sysadmin Grub Help?

rdan Well-Known Member

eva2000 Administrator Staff Member

rdan Well-Known Member

rdan Well-Known Member

rdan Well-Known Member

rdan Well-Known Member

rdan Well-Known Member

pamamolf Premium Member Premium Member

rdan Well-Known Member

eva2000 Administrator Staff Member

Matt Well-Known Member

Matt Well-Known Member

eva2000 Administrator Staff Member

Matt Well-Known Member

Matt Well-Known Member

eva2000 Administrator Staff Member

Matt Well-Known Member

Matt Well-Known Member

eva2000 Administrator Staff Member

Matt Well-Known Member

eva2000 Administrator Staff Member

.

Log in / Register

Useful Searches

Want to subscribe to topics you're interested in?

Sysadmin Grub Help?

rdan Well-Known Member

eva2000 Administrator Staff Member

rdan Well-Known Member

rdan Well-Known Member

rdan Well-Known Member

rdan Well-Known Member

rdan Well-Known Member

pamamolf Premium Member Premium Member

rdan Well-Known Member

eva2000 Administrator Staff Member

Matt Well-Known Member

Matt Well-Known Member

eva2000 Administrator Staff Member

Matt Well-Known Member

Matt Well-Known Member

eva2000 Administrator Staff Member

Matt Well-Known Member

Matt Well-Known Member

eva2000 Administrator Staff Member

Matt Well-Known Member

eva2000 Administrator Staff Member

.