ディレクトリーごとの容量を知る方法です。
duコマンドで確認する
-sオプションで合計を、-hで人が読みやすい形式で表示します。
$ sudo du -sh /boot/*
9.0M /boot/System.map-5.14.0-570.12.1.el9_6.x86_64
9.0M /boot/System.map-5.14.0-570.58.1.el9_6.x86_64
224K /boot/config-5.14.0-570.12.1.el9_6.x86_64
232K /boot/config-5.14.0-570.58.1.el9_6.x86_64
7.1M /boot/efi
2.3M /boot/grub2
164M /boot/initramfs-0-rescue-7f0ad21e475249ca9ba63bb2cad136e2.img
37M /boot/initramfs-5.14.0-570.12.1.el9_6.x86_64.img
37M /boot/initramfs-5.14.0-570.12.1.el9_6.x86_64kdump.img
37M /boot/initramfs-5.14.0-570.58.1.el9_6.x86_64.img
37M /boot/initramfs-5.14.0-570.58.1.el9_6.x86_64kdump.img
16K /boot/loader
0 /boot/symvers-5.14.0-570.12.1.el9_6.x86_64.gz
0 /boot/symvers-5.14.0-570.58.1.el9_6.x86_64.gz
15M /boot/vmlinuz-0-rescue-7f0ad21e475249ca9ba63bb2cad136e2
15M /boot/vmlinuz-5.14.0-570.12.1.el9_6.x86_64
15M /boot/vmlinuz-5.14.0-570.58.1.el9_6.x86_64大きい順に並べ替える。
$ sudo du -sh /boot/* | sort -hr
164M /boot/initramfs-0-rescue-7f0ad21e475249ca9ba63bb2cad136e2.img
37M /boot/initramfs-5.14.0-570.58.1.el9_6.x86_64kdump.img
37M /boot/initramfs-5.14.0-570.58.1.el9_6.x86_64.img
37M /boot/initramfs-5.14.0-570.12.1.el9_6.x86_64kdump.img
37M /boot/initramfs-5.14.0-570.12.1.el9_6.x86_64.img
15M /boot/vmlinuz-5.14.0-570.58.1.el9_6.x86_64
15M /boot/vmlinuz-5.14.0-570.12.1.el9_6.x86_64
15M /boot/vmlinuz-0-rescue-7f0ad21e475249ca9ba63bb2cad136e2
9.0M /boot/System.map-5.14.0-570.58.1.el9_6.x86_64
9.0M /boot/System.map-5.14.0-570.12.1.el9_6.x86_64
7.1M /boot/efi
2.3M /boot/grub2
232K /boot/config-5.14.0-570.58.1.el9_6.x86_64
224K /boot/config-5.14.0-570.12.1.el9_6.x86_64
16K /boot/loader
0 /boot/symvers-5.14.0-570.58.1.el9_6.x86_64.gz
0 /boot/symvers-5.14.0-570.12.1.el9_6.x86_64.gz