If the boot process does not succeed, you have several options to debug the situation.
Identifying your problem area
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Remove ''rhgb'' and ''quiet'' from the kernel command line
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Add ''rd.shell'' to the kernel command line. This will present a shell should dracut be unable to locate your root device
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Add ''rd.shell rd.debug log_buf_len=1M'' to the kernel command line so that dracut shell commands are printed as they are executed
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The file /run/initramfs/rdsosreport.txt is generated, which contains all the logs and the output of all significant tools, which are mentioned later.
If you want to save that output, simply mount /boot by hand or insert an USB stick and mount that. Then you can store the output for later inspection.