Fedora 27（Btrfs分区SSD）无法启动，求助解决启动报错问题

算力阿峰

2026-5-19

Hey there, let's work through this frustrating boot issue with your Fedora 27 and Btrfs setup—you've got two main hurdles here: a corrupted Btrfs filesystem and a locked root account blocking rescue mode access. Let's tackle them one by one.

Step 1: Bypass the Locked Root Account to Access Rescue Mode

The "root account is locked" error is stopping you from getting into the rescue console, so we'll use a GRUB trick to gain access and reset the root password:

When the GRUB menu pops up, select the rescue mode entry and press e to edit its boot parameters.
Look for the line starting with linux (it'll have a bunch of kernel options). At the very end of this line, add rd.break.
Press Ctrl+X to boot with this modified configuration. You'll drop into an emergency shell where the root filesystem is mounted read-only at /sysroot.
Remount it as read-write to make changes:
```
mount -o remount,rw /sysroot
```
Switch to the actual root environment:
```
chroot /sysroot
```
Now reset the root password (follow the prompts to enter and confirm a new one):
```
passwd root
```
Exit the chroot environment:
```
exit
```
Remount the filesystem back to read-only:
```
mount -o remount,ro /sysroot
```
Finally, start the normal init process to enter rescue mode:
```
exec /sbin/init
```

You should now have access to the rescue console without the lock error.

Step 2: Repair the Corrupted Btrfs Filesystem

Now that you're in rescue mode, let's fix the Btrfs issues you're seeing (bad tree blocks, orphan entries, pending checksums):

First, identify your Btrfs root partition. Run blkid to list all partitions—look for the one with TYPE="btrfs" (it's usually something like /dev/mapper/fedora-root or /dev/sda3).
Unmount the partition if it's already mounted (rescue mode might mount it automatically, so check with mount first):
```
umount /dev/your-btrfs-partition
```
Run a read-only check first to assess the damage (this won't modify your data):
```
btrfs check --readonly /dev/your-btrfs-partition
```
This will confirm the bad tree blocks and other issues you saw earlier.
If the read-only check confirms corruption, run the repair tool. Warning: This will modify your filesystem—if you can, back up any critical data first (e.g., by connecting the SSD to another computer or using a Live USB to mount it read-only).
```
btrfs check --repair /dev/your-btrfs-partition
```
This command will fix orphan entries, repair bad tree blocks, and resolve the pending checksum issues.
After repair, test mounting the partition to make sure it works:
```
mount /dev/your-btrfs-partition /mnt
```
You can navigate to /mnt and check if your files are accessible.

Step 3: Post-Repair Checks to Ensure Bootability

Once the filesystem is repaired, let's make sure your system can boot properly:

If you're still in the chroot environment (from Step 1), regenerate the initramfs to ensure all filesystem drivers are up to date:
```
dracut -f
```
Update your GRUB configuration to make sure it points to the correct partition:
- For BIOS systems:
```
grub2-mkconfig -o /boot/grub2/grub.cfg
```
- For UEFI systems:
```
grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg
```
Exit rescue mode and reboot your laptop. Try booting with your default kernel entry—this should work now if the repair was successful.

Important Notes

The btrfs check --repair command is a last resort—always prioritize backing up data before running it if possible.
If you keep seeing filesystem corruption after repair, it might be a sign of SSD hardware failure. Run a SMART check to verify:
```
smartctl -a /dev/sda
```
Fedora 27 reached end-of-life years ago, so it doesn't receive security updates or bug fixes. Once you get your system up and running, consider upgrading to a supported version of Fedora for better stability.

内容的提问来源于stack exchange，提问作者horizonbrave