You said:
manjaro linux, after pacman updating the system, it sais the boot fails


ChatGPT said:
If your Manjaro system fails to boot after a pacman system update (usually with sudo pacman -Syu), here’s how to start diagnosing and recovering it.

⚠️ Common Symptoms
GRUB doesn’t show up, or gives an error like error: file not found

Boot hangs on black screen

Kernel panic

You land in an emergency shell

You get initramfs errors or cannot find UUID=... messages

✅ Step-by-step Recovery Guide
1. Boot into a Live USB
   Use your Manjaro installation USB (or another Linux distro).

2. Mount Your Root Partition
   You’ll need to find and mount your root partition (and optionally /boot or /boot/efi):

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sudo su  # get root access

lsblk  # find your partitions
Assume your root is /dev/sda2 and EFI is /dev/sda1, run:

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mount /dev/sda2 /mnt
mount /dev/sda1 /mnt/boot/efi  # if you use EFI
3. Chroot into Your System
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   manjaro-chroot /mnt /bin/bash
   This puts you inside your installed system as if you booted it.

Now Fix the Boot Issue Depending on the Cause
A. GRUB Reinstallation (safe default)
Run this inside chroot:

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grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=manjaro --recheck
grub-mkconfig -o /boot/grub/grub.cfg
Use --target=i386-pc /dev/sdX if using legacy BIOS instead of EFI.

B. Regenerate Initramfs
If kernel or hooks changed:

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mkinitcpio -P
C. Reinstall Kernel (if broken)
You may want to ensure the kernel is present:

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mhwd-kernel -li        # list installed kernels
mhwd-kernel -i linux64 # replace `64` with actual version like `66`
D. Update Bootloader Entries
If boot entries are broken or missing:

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efibootmgr -v  # list EFI entries
You can clean and recreate entries if needed.

4. Exit and Reboot
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   exit
   reboot
   🧩 Optional: Diagnose Logs
   If you can get into the emergency shell or log in via chroot, look at:

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journalctl -xb
Look for any kernel/initramfs/disk/UUID-related errors.

🛡️ Prevent Future Boot Breakages
Always update via TTY or console, not via GUI if it's a big update.

Don’t interrupt mkinitcpio or grub-mkconfig during updates.

Backup /boot before major kernel or GRUB upgrades.

If you want to post specific errors (e.g. GRUB, UUID, journalctl logs), I can help pinpoint exactly what broke.