我無法進入我的 CentOS 8，無法切換 root，’/sysroot'

我只有圖片。而且我不能很好地寫出問題。

我正在啟動我的筆記型電腦（使用Windows 10 Proand CentOS8）。

systemctl status initrd-switch-root.service

https://i.stack.imgur.com/fuGRU.jpg

https://i.stack.imgur.com/CAQ7Y.jpg

最後一張圖Failed to Start Switch Root。和

Failed to switch root: Specified switch root path '/sysroot' does not seem to be an OS tree. os-release file is missing.

https://i.stack.imgur.com/onWbr.jpg

做一個**ls -al /sysroot**目錄是空的。

我dmesg得到了：

知道為什麼會發生這種故障嗎？

很明顯，我該如何解決呢？

在圖像中，唯一有效的條目是 Rescue Windows 條目上方的 CentOS 條目CentOS Linux (0-rescue-***)

請幫忙。

編輯 1：

使用解決方案https://unix.stackexchange.com/a/212710/117555

1. 檢查開發->ls -al /dev/s*
2. 插入 U 盤
3. 再次檢查->ls -al /dev/s*
4. 創建掛載目錄 ->mkdir -p /mnt/logError_SwitchRoot
5. 安裝棒->mount /dev/sd[letter][number] /mnt/logError_SwitchRoot
6. 複製文件->cp /run/initramfs/rdsosreport.txt /mnt/logError_SwitchRoot
7. 解除安裝棍子->umount /mnt/logError_SwitchRoot

我現在在https://drive.google.com/file/d/1vMK0QAoyMZ7xTibDqn8Y_Y9nohUStN-6/view?usp=sharingrdsosreport.txt上存檔

檢查文件：

   /dev/nvme0n1p1: LABEL="SYSTEM_DRV" UUID="5464-19F2" TYPE="vfat" PARTLABEL="EFI system partition" PARTUUID="31ebd6ef-ec98-42c7-a57b-7855c2c9a1f3"
   /dev/nvme0n1p5: LABEL="WINRE_DRV" UUID="C2EC6975EC69651F" TYPE="ntfs" PARTLABEL="Basic data partition" PARTUUID="51363955-3d66-4f95-92de-732ccff36936"
   /dev/nvme0n1p6: LABEL="boot_efi" UUID="6E91-210B" TYPE="vfat" PARTLABEL="EFI System Partition" PARTUUID="5291c15b-2f5c-42a0-b3e3-2c69f27b801b"
   /dev/nvme0n1p7: UUID="7471a525-f8c8-4a77-819e-65b40c04eaaf" TYPE="ext4" PARTUUID="13b3a31b-193f-4ef5-9076-a083cdc857de"
   /dev/nvme0n1p8: UUID="d1ee8d12-37a1-43e7-9f13-0f97544864aa" TYPE="ext4" PARTUUID="88cd29e2-3b20-44e4-bdf4-0ce02d9008d6"
   /dev/nvme0n1p9: UUID="54f24598-4a21-4875-bacd-61c060de891f" TYPE="ext4" PARTUUID="d1126852-240f-4e03-a8f3-86f769b3fd77"
   /dev/nvme0n1p10: UUID="3fc5f4f8-566b-48e2-85e1-59f5dccdcb57" TYPE="ext4" PARTUUID="b2190e39-3ee8-4a41-a156-6a866ee8ee14"
   /dev/nvme0n1p11: UUID="42640b78-ce32-403c-8705-8c12e2d02855" TYPE="swap" PARTUUID="acc07fc2-4876-42c0-9d02-b066c04cfd4f"
   /dev/sda1: LABEL="EFI" UUID="67E3-17ED" TYPE="vfat" PARTLABEL="EFI System Partition" PARTUUID="5cd547d2-a0ef-4c51-8a00-9877055342bb"
   /dev/nvme0n1: PTUUID="e24c5cda-1faa-490b-b677-7c4792194960" PTTYPE="gpt"
   /dev/nvme0n1p2: PARTLABEL="Microsoft reserved partition" PARTUUID="b692aa4c-0d83-40f0-8707-cd0b49290b00"
   /dev/nvme0n1p3: PARTLABEL="Basic data partition" PARTUUID="72f573a8-4b1d-40ab-900c-5b2b608fa964"
   /dev/nvme0n1p4: PARTLABEL="Basic data partition" PARTUUID="50badba8-609d-4a24-b957-c8f90b8d7d80"
   /dev/sda2: PARTUUID="f704e2d2-a0b9-4fa4-9b19-cef07c8b6668"

和

BOOT_IMAGE=(hd1,gpt7)/vmlinuz-5.8.0-1.el8.elrepo.x86_64

編輯 2：

我找到了一些我的安裝圖片（2020 年 7 月 5 日 15:05，供我參考）！

DATA
   /home
   nvme0n1p8

SYSTEM
   /boot/efi
   nvme0n1p6

   /var
   nvme0n1p10

   /
   nvme0n1p9

   /boot
   nvme0n1p7

   swap
   nvme0n1p11

這是我的資訊（重啟後）

[root@centos /]# lsblk -o NAME,MAJ:MIN,RM,SIZE,RO,FSTYPE,UUID,MOUNTPOINT
NAME         MAJ:MIN RM   SIZE RO FSTYPE   UUID                                 MOUNTPOINT
loop0          7:0    0  29.8M  1 squashfs                                      /var/lib/snapd/snap/snapd/8140
loop1          7:1    0    55M  1 squashfs                                      /var/lib/snapd/snap/core18/1754
loop2          7:2    0  29.9M  1 squashfs                                      /var/lib/snapd/snap/snapd/8542
loop3          7:3    0    55M  1 squashfs                                      /var/lib/snapd/snap/core18/1880
loop4          7:4    0    97M  1 squashfs                                      /var/lib/snapd/snap/core/9665
loop5          7:5    0  62.1M  1 squashfs                                      /var/lib/snapd/snap/gtk-common-themes/1506
nvme0n1      259:0    0   477G  0                                               
├─nvme0n1p1  259:1    0   260M  0 vfat     5464-19F2                            
├─nvme0n1p2  259:2    0    16M  0                                               
├─nvme0n1p3  259:3    0 115.7G  0                                               
├─nvme0n1p4  259:4    0   104G  0                                               
├─nvme0n1p5  259:5    0  1000M  0 ntfs     C2EC6975EC69651F                     
├─nvme0n1p6  259:6    0     1G  0 vfat     6E91-210B                            /boot/efi
├─nvme0n1p7  259:7    0     1G  0 ext4     7471a525-f8c8-4a77-819e-65b40c04eaaf /boot
├─nvme0n1p8  259:8    0   174G  0 ext4     d1ee8d12-37a1-43e7-9f13-0f97544864aa /home
├─nvme0n1p9  259:9    0    32G  0 ext4     54f24598-4a21-4875-bacd-61c060de891f /
├─nvme0n1p10 259:10   0    24G  0 ext4     3fc5f4f8-566b-48e2-85e1-59f5dccdcb57 /var
└─nvme0n1p11 259:11   0    24G  0 swap     42640b78-ce32-403c-8705-8c12e2d02855 [SWAP]
[root@centos /]# 

我有這個清單…

/tmp/nvme0n1p6/:
total 16
drwxr-xr-x 4 root root 4096 Jan  1  1970 .
drwxr-xr-x 6 root root  120 Jun 11 02:11 ..
drwxr-xr-x 4 root root 4096 Jul  5  2020 EFI
-rwxr-xr-x 1 root root 4096 Jan  1  1980 FSCK0000.REC
drwxr-xr-x 2 root root 4096 Jul 22  2020 System Volume Information

/tmp/nvme0n1p6/EFI:
total 16
drwxr-xr-x 4 root root 4096 Jul  5  2020 .
drwxr-xr-x 4 root root 4096 Jan  1  1970 ..
drwxr-xr-x 2 root root 4096 Jul  5  2020 BOOT
drwxr-xr-x 3 root root 4096 Aug 23  2020 centos

/tmp/nvme0n1p6/EFI/BOOT:
total 1544
drwxr-xr-x 2 root root    4096 Jul  5  2020 .
drwxr-xr-x 4 root root    4096 Jul  5  2020 ..
-rwxr-xr-x 1 root root 1211224 May  7  2020 BOOTX64.EFI
-rwxr-xr-x 1 root root  356800 May  7  2020 fbx64.efi

/tmp/nvme0n1p6/EFI/centos:
total 5360
drwxr-xr-x 3 root root    4096 Aug 23  2020 .
drwxr-xr-x 4 root root    4096 Jul  5  2020 ..
-rwxr-xr-x 1 root root     134 May  7  2020 BOOTX64.CSV
drwxr-xr-x 2 root root    4096 Apr 14  2020 fonts
-rwxr-xr-x 1 root root    5502 Jul  5  2020 grub.cfg
-rwxr-xr-x 1 root root       0 Aug 23  2020 grubenv
-rwxr-xr-x 1 root root 1877384 Apr 14  2020 grubx64.efi
-rwxr-xr-x 1 root root 1160136 May  7  2020 mmx64.efi
-rwxr-xr-x 1 root root 1205152 May  7  2020 shimx64-centos.efi
-rwxr-xr-x 1 root root 1211224 May  7  2020 shimx64.efi

/tmp/nvme0n1p6/EFI/centos/fonts:
total 8
drwxr-xr-x 2 root root 4096 Apr 14  2020 .
drwxr-xr-x 3 root root 4096 Aug 23  2020 ..

/tmp/nvme0n1p6/System Volume Information:
total 8
drwxr-xr-x 2 root root 4096 Jul 22  2020 .
drwxr-xr-x 4 root root 4096 Jan  1  1970 ..

這是另一個列表

/tmp/nvme0n1p7/:
total 360344
dr-xr-xr-x 7 root   root      4096 Aug 11  2020 .
drwxr-xr-x 7 root   root       140 Jun 11 02:17 ..
-rw-r--r-- 1 root   root       166 Dec  4  2019 .vmlinuz-4.18.0-147.el8.x86_64.hmac
-rw-r--r-- 1 root   root       172 Jun 10  2020 .vmlinuz-4.18.0-193.6.3.el8_2.x86_64.hmac
drwxrwxrwx 2 nobody 65534     4096 Sep  7  2020 System Volume Information
-rw------- 1 root   root   3838259 Dec  4  2019 System.map-4.18.0-147.el8.x86_64
-rw------- 1 root   root   3910484 Jun 10  2020 System.map-4.18.0-193.6.3.el8_2.x86_64
-rw------- 1 root   root   4654688 Jul  7  2020 System.map-5.7.8-1.el8.elrepo.x86_64
-rw------- 1 root   root   4714527 Aug  2  2020 System.map-5.8.0-1.el8.elrepo.x86_64
-rw-r--r-- 1 root   root    184613 Dec  4  2019 config-4.18.0-147.el8.x86_64
-rw-r--r-- 1 root   root    187643 Jun 10  2020 config-4.18.0-193.6.3.el8_2.x86_64
-rw-r--r-- 1 root   root    197087 Jul  7  2020 config-5.7.8-1.el8.elrepo.x86_64
-rw-r--r-- 1 root   root    201589 Aug  2  2020 config-5.8.0-1.el8.elrepo.x86_64
drwxr-xr-x 2 root   root      4096 Jul  5  2020 efi
drwx------ 2 root   root      4096 Apr 14  2020 grub2
-rw------- 1 root   root  71713525 Jul  5  2020 initramfs-0-rescue-fb78af0a9247484aad9831a10a928084.img
-rw------- 1 root   root  49320247 Jul  6  2020 initramfs-4.18.0-147.el8.x86_64.img
-rw------- 1 root   root  18223920 Jul  6  2020 initramfs-4.18.0-147.el8.x86_64kdump.img
-rw------- 1 root   root  49864041 Jul  6  2020 initramfs-4.18.0-193.6.3.el8_2.x86_64.img
-rw------- 1 root   root  18642820 Jul  6  2020 initramfs-4.18.0-193.6.3.el8_2.x86_64kdump.img
-rw------- 1 root   root  50414753 Jul 15  2020 initramfs-5.7.8-1.el8.elrepo.x86_64.img
-rw------- 1 root   root  50395127 Aug 11  2020 initramfs-5.8.0-1.el8.elrepo.x86_64.img
drwxr-xr-x 3 root   root      4096 Jul  5  2020 loader
drwx------ 2 root   root     16384 Jul  5  2020 lost+found
-rwxr-xr-x 1 root   root   8106744 Jul  5  2020 vmlinuz-0-rescue-fb78af0a9247484aad9831a10a928084
-rwxr-xr-x 1 root   root   8106744 Dec  4  2019 vmlinuz-4.18.0-147.el8.x86_64
-rwxr-xr-x 1 root   root   8913656 Jun 10  2020 vmlinuz-4.18.0-193.6.3.el8_2.x86_64
-rwxr-xr-x 1 root   root   8558528 Jul  7  2020 vmlinuz-5.7.8-1.el8.elrepo.x86_64
-rwxr-xr-x 1 root   root   8742176 Aug  2  2020 vmlinuz-5.8.0-1.el8.elrepo.x86_64

/tmp/nvme0n1p7/System Volume Information:
total 12
drwxrwxrwx 2 nobody 65534 4096 Sep  7  2020 .
dr-xr-xr-x 7 root   root  4096 Aug 11  2020 ..
-rw-rw-rw- 1 nobody 65534   76 Sep  7  2020 IndexerVolumeGuid

/tmp/nvme0n1p7/efi:
total 8
drwxr-xr-x 2 root root 4096 Jul  5  2020 .
dr-xr-xr-x 7 root root 4096 Aug 11  2020 ..

/tmp/nvme0n1p7/grub2:
total 8
drwx------ 2 root root 4096 Apr 14  2020 .
dr-xr-xr-x 7 root root 4096 Aug 11  2020 ..
lrwxrwxrwx 1 root root   25 Apr 14  2020 grubenv -> ../efi/EFI/centos/grubenv

/tmp/nvme0n1p7/loader:
total 12
drwxr-xr-x 3 root root 4096 Jul  5  2020 .
dr-xr-xr-x 7 root root 4096 Aug 11  2020 ..
drwx------ 2 root root 4096 Aug 11  2020 entries

/tmp/nvme0n1p7/loader/entries:
total 28
drwx------ 2 root root 4096 Aug 11  2020 .
drwxr-xr-x 3 root root 4096 Jul  5  2020 ..
-rw-r--r-- 1 root root  395 Jul  5  2020 fb78af0a9247484aad9831a10a928084-0-rescue.conf
-rw-r--r-- 1 root root  323 Jul  5  2020 fb78af0a9247484aad9831a10a928084-4.18.0-147.el8.x86_64.conf
-rw-r--r-- 1 root root  353 Jul  6  2020 fb78af0a9247484aad9831a10a928084-4.18.0-193.6.3.el8_2.x86_64.conf
-rw-r--r-- 1 root root  356 Jul 15  2020 fb78af0a9247484aad9831a10a928084-5.7.8-1.el8.elrepo.x86_64.conf
-rw-r--r-- 1 root root  356 Aug 11  2020 fb78af0a9247484aad9831a10a928084-5.8.0-1.el8.elrepo.x86_64.conf

/tmp/nvme0n1p7/lost+found:
total 20
drwx------ 2 root root 16384 Jul  5  2020 .
dr-xr-xr-x 7 root root  4096 Aug 11  2020 ..

我怎麼知道 /sysroot 是什麼？

我沒有/boot/efi掛載，也沒有 /boot 目錄！

如何掛載/boot/efi？

grub 命令不起作用！

編輯 3：

為了解決這個問題

# grub2-editenv list
grub2-editenv: error: invalid environment block.
# grub2-editenv set
grub2-editenv: error: invalid environment block.
# 

我關注https://access.redhat.com/solutions/5622731

# mv /boot/grub2/grubenv /boot/grub2/grubenv.bak
# grub2-set-default 1
# grub2-editenv list
saved_entry=1
# grub2-editenv set
#

編輯 4：

https://www.golinuxcloud.com/update-grub2-grubby-grub2-editenv-rhel-8/ 檢查https://www.techbrown.com/change-default-grub-entries-timeout-centos-rhel/ 有效為了我

# grub2-editenv - set "kernelopts=root=UUID=54f24598-4a21-4875-bacd-61c060de891f ro"

重啟後

[root@centos /]# grub2-editenv list
saved_entry=1
boot_success=1
kernelopts=root=UUID=54f24598-4a21-4875-bacd-61c060de891f ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet 
[root@centos /]# 

編輯 5：

[root@centos /]# grub2-editenv list
saved_entry=fb78af0a9247484aad9831a10a928084-4.18.0-193.14.2.el8_2.x86_64
boot_success=1
kernelopts=root=UUID=54f24598-4a21-4875-bacd-61c060de891f ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet 
boot_indeterminate=1
[root@centos /]# 

對我來說，這條線很奇怪：

saved_entry=fb78af0a9247484aad9831a10a928084-4.18.0-193.14.2.el8_2.x86_64

編輯 6：

[root@centos /]# ls -al /boot/efi/EFI/centos/
total 5820
drwx------. 3 root root    4096 Jun 11 13:50 .
drwx------. 4 root root    4096 Nov 16  2020 ..
-rwx------. 1 root root     134 Jul 31  2020 BOOTX64.CSV
drwx------. 2 root root    4096 Mar  2 16:03 fonts
-rwx------. 1 root root    5502 Jul  5  2020 grub.cfg
-rwx------. 1 root root       0 Aug 23  2020 grubenv.bak
-rwx------. 1 root root 2285336 Mar  2 16:03 grubx64.efi
-rwx------. 1 root root 1162400 Jul 31  2020 mmx64.efi
-rwx------. 1 root root 1238416 Jul 31  2020 shimx64-centos.efi
-rwx------. 1 root root 1244496 Jul 31  2020 shimx64.efi
[root@centos /]# ls -al /boot/grub2/
total 20
drwx------. 2 root root 4096 Jun 12 22:20 .
dr-xr-xr-x. 7 root root 4096 Jun 11 13:58 ..
-rw-r--r--. 1 root root 5503 Jun 11 05:01 grub.cfg
-rw-------. 1 root root 1024 Jun 12 22:20 grubenv
lrwxrwxrwx. 1 root root   25 Apr 14  2020 grubenv.bak -> ../efi/EFI/centos/grubenv
[root@centos /]# cat /boot/grub2/grubenv
# GRUB Environment Block
saved_entry=fb78af0a9247484aad9831a10a928084-4.18.0-305.3.1.el8.x86_64
boot_success=1
kernelopts=root=UUID=54f24598-4a21-4875-bacd-61c060de891f ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet 
boot_indeterminate=1
#################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################[root@centos /]#

明顯有問題！！！該/efi/EFI/centos/grubenv文件不存在，/boot/grub2/grubenv似乎格式錯誤。

根據此連結https://bugzilla.redhat.com/show_bug.cgi?id=1435435 物理文件必須位於/efi/EFI/centos/grubenv並且符號連結/boot/grub2/grubenv應指向/efi/EFI/centos/grubenv.

如何創建/efi/EFI/centos/grubenv文件，而不直接編輯它？

和

[root@centos /]# awk -F\' '/^menuentry/ {print $2}' /boot/grub2/grub.cfg
Windows Boot Manager (on /dev/nvme0n1p1)
System setup
[root@centos /]#

[root@centos /]# awk -F\' '/^menuentry/ {print $2}' /boot/efi/EFI/centos/grub.cfg
Windows Boot Manager (on /dev/nvme0n1p1)
System setup
[root@centos /]#

[root@centos /]# grub2-mkconfig -o /boot/grub2/grub.cfg.bck
Generating grub configuration file ...
Found Windows Boot Manager on /dev/nvme0n1p1@/EFI/Microsoft/Boot/bootmgfw.efi
Adding boot menu entry for EFI firmware configuration
done
[root@centos /]#

[root@centos /]# awk -F\' '/^menuentry/ {print $2}' /boot/grub2/grub.cfg.bck
Windows Boot Manager (on /dev/nvme0n1p1)
System setup
[root@centos /]#

我複製到測試：

# cp /boot/grub2/grubenv /boot/efi/EFI/centos/

條目沒有出現？

我按照這個連結

# ls -al /boot/loader/entries
total 36
drwx------. 2 root root 4096 Jun 11 13:57 .
drwxr-xr-x. 3 root root 4096 Jul  5  2020 ..
-rw-r--r--. 1 root root  395 Jul  5  2020 fb78af0a9247484aad9831a10a928084-0-rescue.conf
-rw-r--r--. 1 root root  358 Jun 11 11:36 fb78af0a9247484aad9831a10a928084-4.18.0-193.14.2.el8_2.x86_64.conf
-rw-r--r--. 1 root root  353 Jul  5  2020 fb78af0a9247484aad9831a10a928084-4.18.0-193.6.3.el8_2.x86_64.conf
-rw-r--r--. 1 root root  336 Jun 11 13:57 fb78af0a9247484aad9831a10a928084-4.18.0-305.3.1.el8.x86_64.conf
-rw-r--r--. 1 root root  366 Jun 11 12:05 fb78af0a9247484aad9831a10a928084-5.12.10-1.el8.elrepo.x86_64.conf
-rw-r--r--. 1 root root  356 Jul 15  2020 fb78af0a9247484aad9831a10a928084-5.7.8-1.el8.elrepo.x86_64.conf
-rw-r--r--. 1 root root  356 Aug 11  2020 fb78af0a9247484aad9831a10a928084-5.8.0-1.el8.elrepo.x86_64.conf
[root@centos /]#

並按照這個答案https://stackoverflow.com/a/64637392

我列出所有# grubby --info=ALL

我查看一個特定的# grubby --info 0

檢查我的預設設置

[root@centos /]# grubby --info DEFAULT
index=3
kernel="/boot/vmlinuz-4.18.0-305.3.1.el8.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-4.18.0-305.3.1.el8.x86_64.img $tuned_initrd"
title="CentOS Linux (4.18.0-305.3.1.el8.x86_64) 8"
id="fb78af0a9247484aad9831a10a928084-4.18.0-305.3.1.el8.x86_64"
[root@centos /]#

我試圖用 #grubby --args amd_iommu=on --update-kernel=/boot/vmlinuz-$(uname -r)和 with更改預設值，grubby --args amd_iommu=on --update-kernel 2但它不起作用（使用# grubby --info DEFAULT）！

審查 0 個條目

[root@centos /]# grubby --info 0
index=0
kernel="/boot/vmlinuz-5.12.10-1.el8.elrepo.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params amd_iommu=on"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-5.12.10-1.el8.elrepo.x86_64.img $tuned_initrd"
title="Red Hat Enterprise Linux (5.12.10-1.el8.elrepo.x86_64) 8.4 (Ootpa)"
id="fb78af0a9247484aad9831a10a928084-5.12.10-1.el8.elrepo.x86_64"
[root@centos /]#

並遵循https://unix.stackexchange.com/a/394889/400726

按標題選擇：

[root@centos /]# grub2-editenv - set saved_entry='Red Hat Enterprise Linux (5.12.10-1.el8.elrepo.x86_64) 8.4 (Ootpa)'
[root@centos /]# 

顯然它改變了。

[root@centos /]# grubby --info DEFAULT
index=0
kernel="/boot/vmlinuz-5.12.10-1.el8.elrepo.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params amd_iommu=on"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-5.12.10-1.el8.elrepo.x86_64.img $tuned_initrd"
title="Red Hat Enterprise Linux (5.12.10-1.el8.elrepo.x86_64) 8.4 (Ootpa)"
id="fb78af0a9247484aad9831a10a928084-5.12.10-1.el8.elrepo.x86_64"
[root@centos /]#

重新啟動，但它也不起作用！

審查

[root@centos /]# cmp /boot/efi/EFI/centos/grubenv /boot/grub2/grubenv
/boot/efi/EFI/centos/grubenv /boot/grub2/grubenv differ: byte 38, line 2
[root@centos /]# 

文件已更改，不一樣！

[root@centos /]# cat /boot/efi/EFI/centos/grubenv
# GRUB Environment Block
saved_entry=fb78af0a9247484aad9831a10a928084-4.18.0-305.3.1.el8.x86_64
boot_success=0
kernelopts=root=UUID=54f24598-4a21-4875-bacd-61c060de891f ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet 
boot_indeterminate=0
##############################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################[root@centos /]# 

[root@centos /]# cat /boot/grub2/grubenv
# GRUB Environment Block
saved_entry=Red Hat Enterprise Linux (5.12.10-1.el8.elrepo.x86_64) 8.4 (Ootpa)
boot_success=1
kernelopts=root=UUID=54f24598-4a21-4875-bacd-61c060de891f ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet 
boot_indeterminate=1
##############################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################################[root@centos /]# 

我在嘗試

[root@centos /]# rm /boot/grub2/grubenv.bak
rm: remove symbolic link '/boot/grub2/grubenv.bak'? y
[root@centos /]#
[root@centos /]# rm /boot/efi/EFI/centos/grubenv.bak
rm: remove regular empty file '/boot/efi/EFI/centos/grubenv.bak'? y
[root@centos /]#

[root@centos /]# ln -s /boot/grub2/grubenv /boot/efi/EFI/centos/grubenv
ln: failed to create symbolic link '/boot/efi/EFI/centos/grubenv': Operation not permitted
[root@centos /]#

我更喜歡符號連結（但是，我了解情況https://www.linuxquestions.org/questions/suse-opensuse-60/boot-is-not-allowing-symbolic-link-creation-4175682262/#post6166967）！

[root@centos /]# cp /boot/grub2/grubenv /boot/efi/EFI/centos/
[root@centos /]#

有什麼解決辦法嗎？

[root@centos /]# ls -al /boot/grub2/
total 28
drwx------. 2 root root 4096 Jun 12 23:07 .
dr-xr-xr-x. 7 root root 4096 Jun 11 13:58 ..
-rw-r--r--. 1 root root 5503 Jun 11 05:01 grub.cfg
-rw-r--r--. 1 root root 6956 Jun 12 22:59 grub.cfg.bck
-rw-------. 1 root root 1024 Jun 12 22:59 grubenv
[root@centos /]#

[root@centos /]# ls -al /boot/efi/EFI/centos/
total 5824
drwx------. 3 root root    4096 Jun 12 23:09 .
drwx------. 4 root root    4096 Nov 16  2020 ..
-rwx------. 1 root root     134 Jul 31  2020 BOOTX64.CSV
drwx------. 2 root root    4096 Mar  2 16:03 fonts
-rwx------. 1 root root    5502 Jul  5  2020 grub.cfg
-rwx------. 1 root root    1024 Jun 12 23:06 grubenv
-rwx------. 1 root root 2285336 Mar  2 16:03 grubx64.efi
-rwx------. 1 root root 1162400 Jul 31  2020 mmx64.efi
-rwx------. 1 root root 1238416 Jul 31  2020 shimx64-centos.efi
-rwx------. 1 root root 1244496 Jul 31  2020 shimx64.efi
[root@centos /]#

編輯 7

記住最初的符號連結問題，我需要修復。

這裡我們有 DEFAULT Entry… 作為複制的結果。

[root@centos /]# grubby --info DEFAULT
index=0
kernel="/boot/vmlinuz-5.12.10-1.el8.elrepo.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params amd_iommu=on"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-5.12.10-1.el8.elrepo.x86_64.img $tuned_initrd"
title="Red Hat Enterprise Linux (5.12.10-1.el8.elrepo.x86_64) 8.4 (Ootpa)"
id="fb78af0a9247484aad9831a10a928084-5.12.10-1.el8.elrepo.x86_64"
[root@centos /]#

我需要測試更改，但首先我需要檢查所有條目。

[root@centos /]# grubby --info=ALL
index=0
kernel="/boot/vmlinuz-5.12.10-1.el8.elrepo.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params amd_iommu=on"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-5.12.10-1.el8.elrepo.x86_64.img $tuned_initrd"
title="Red Hat Enterprise Linux (5.12.10-1.el8.elrepo.x86_64) 8.4 (Ootpa)"
id="fb78af0a9247484aad9831a10a928084-5.12.10-1.el8.elrepo.x86_64"
index=1
kernel="/boot/vmlinuz-5.8.0-1.el8.elrepo.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-5.8.0-1.el8.elrepo.x86_64.img $tuned_initrd"
title="Red Hat Enterprise Linux (5.8.0-1.el8.elrepo.x86_64) 8.2 (Ootpa)"
id="fb78af0a9247484aad9831a10a928084-5.8.0-1.el8.elrepo.x86_64"
index=2
kernel="/boot/vmlinuz-5.7.8-1.el8.elrepo.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-5.7.8-1.el8.elrepo.x86_64.img $tuned_initrd"
title="Red Hat Enterprise Linux (5.7.8-1.el8.elrepo.x86_64) 8.2 (Ootpa)"
id="fb78af0a9247484aad9831a10a928084-5.7.8-1.el8.elrepo.x86_64"
index=3
kernel="/boot/vmlinuz-4.18.0-305.3.1.el8.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-4.18.0-305.3.1.el8.x86_64.img $tuned_initrd"
title="CentOS Linux (4.18.0-305.3.1.el8.x86_64) 8"
id="fb78af0a9247484aad9831a10a928084-4.18.0-305.3.1.el8.x86_64"
index=4
kernel="/boot/vmlinuz-4.18.0-193.14.2.el8_2.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-4.18.0-193.14.2.el8_2.x86_64.img $tuned_initrd"
title="CentOS Linux (4.18.0-193.14.2.el8_2.x86_64) 8 (Core)"
id="fb78af0a9247484aad9831a10a928084-4.18.0-193.14.2.el8_2.x86_64"
index=5
kernel="/boot/vmlinuz-4.18.0-193.6.3.el8_2.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-4.18.0-193.6.3.el8_2.x86_64.img $tuned_initrd"
title="CentOS Linux (4.18.0-193.6.3.el8_2.x86_64) 8 (Core)"
id="fb78af0a9247484aad9831a10a928084-4.18.0-193.6.3.el8_2.x86_64"
index=6
kernel="/boot/vmlinuz-0-rescue-fb78af0a9247484aad9831a10a928084"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-0-rescue-fb78af0a9247484aad9831a10a928084.img"
title="CentOS Linux (0-rescue-fb78af0a9247484aad9831a10a928084) 8 (Core)"
id="fb78af0a9247484aad9831a10a928084-0-rescue"
[root@centos /]#

現在，我嘗試更改條目。

[root@centos /]# grubby --args amd_iommu=on --update-kernel 3
[root@centos /]# grubby --info DEFAULT
index=0
kernel="/boot/vmlinuz-5.12.10-1.el8.elrepo.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params amd_iommu=on"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-5.12.10-1.el8.elrepo.x86_64.img $tuned_initrd"
title="Red Hat Enterprise Linux (5.12.10-1.el8.elrepo.x86_64) 8.4 (Ootpa)"
id="fb78af0a9247484aad9831a10a928084-5.12.10-1.el8.elrepo.x86_64"
[root@centos /]#

（以前不起作用），現在使用替代方式。

[root@centos /]# grub2-editenv - set saved_entry='CentOS Linux (4.18.0-305.3.1.el8.x86_64) 8'
[root@centos /]# grubby --info DEFAULT
index=3
kernel="/boot/vmlinuz-4.18.0-305.3.1.el8.x86_64"
args="ro crashkernel=auto resume=UUID=42640b78-ce32-403c-8705-8c12e2d02855 rhgb quiet $tuned_params amd_iommu=on"
root="UUID=54f24598-4a21-4875-bacd-61c060de891f"
initrd="/boot/initramfs-4.18.0-305.3.1.el8.x86_64.img $tuned_initrd"
title="CentOS Linux (4.18.0-305.3.1.el8.x86_64) 8"
id="fb78af0a9247484aad9831a10a928084-4.18.0-305.3.1.el8.x86_64"
[root@centos /]#

已解決：

Finally, after restart the changes works!!!

總結一下：

• 您在啟動時進入緊急模式
• 報告的錯誤是：

Failed to switch root: Specified switch root path '/sysroot' does not seem to be an OS tree. os-release file is missing.

• 表示rdsosreport.txt實際上沒有安裝任何東西/sysroot，並且/proc/cmdline只有一個核心啟動選項：BOOT_IMAGE=(hd1,gpt7)/vmlinuz-5.8.0-1.el8.elrepo.x86_64.

從rdsosreport.txt資訊來看，似乎應該至少列出root=UUID=54f24598-4a21-4875-bacd-61c060de891f或root=/dev/nvme0n1p9列出類似的內容，以辨識實際的根文件系統。但根本沒有root=選擇。這表明了一個相對簡單的引導載入程序問題，除非還有其他問題。

RHEL/CentOS 8 將此資訊儲存在一個grubenv文件中，在像您這樣的 UEFI 系統中，/boot/efi/EFI/centos/grubenv當所有文件系統都已安裝到其正常位置時，該文件將位於該文件中。該文件應包含如下行：

kernelopts=root=UUID=54f24598-4a21-4875-bacd-61c060de891f ro

您不應grubenv直接編輯文件，而應使用grub2-editenv命令：grub2-editenv list查看設置並grub2-editenv set "kernelopts=root=UUID=54f24598-4a21-4875-bacd-61c060de891f ro"進行設置。

但是要達到可以使用的地步，grub2-editenv您首先需要啟動並執行作業系統。

當 GRUB 菜單出現時，使用箭頭鍵移動到與您希望使用的核心相對應的行（可能是第一行或第三行）。然後按E而不是按Enter。將顯示引導條目以供編輯。找到以 開頭的行linux /vmlinuz-...，將游標移動到該行的末尾，然後鍵入空格和root=/dev/nvme0n1p9。（您也可以使用 UUID 形式，但這樣更難正確輸入。）

然後查看螢幕底部以找到將啟動修改條目的擊鍵（如果我沒記錯的話是Control+ ）。X

如果這可行，您的系統應該可以正常啟動到 CentOS - 僅在這一次。要永久解決該問題，您需要grubenv按照上述方法修復該文件。

引用自：https://unix.stackexchange.com/questions/607292