diff --git a/content/posts/uefi-full-disk-encryption.md b/content/posts/uefi-full-disk-encryption.md
index 2605ad1..ed155e9 100644
--- a/content/posts/uefi-full-disk-encryption.md
+++ b/content/posts/uefi-full-disk-encryption.md
@@ -327,7 +327,8 @@ The file rc.confg also needs to be edited
 rc_configured=YES
 
 # Add local overrides below.
-#
+critical_filesystems_local="OPTIONAL:/var OPTIONAL:/usr"
+
 hostname=marte.local
 dhcpcd=YES
 dhcpcd_flags="-qM wm0"
@@ -343,6 +344,8 @@ For example, my network device is `wm0`.
 And this example hostname is `marte.local`.
 Your network card and requirements may be different.
 
+Also `critical_filesystems_local` variable is quite important. Since our `/usr` filesystem is not mounted at the beginning, some tools may not be available. We need to wait for it to be mounted before executing binaries from `/usr`.
+
 # Unmount and reboot
 
 Umount the new system:
diff --git a/content/posts/uefi-netbsd-archlinux-dual-boot.md b/content/posts/uefi-netbsd-archlinux-dual-boot.md
index 81e003a..21bcce6 100644
--- a/content/posts/uefi-netbsd-archlinux-dual-boot.md
+++ b/content/posts/uefi-netbsd-archlinux-dual-boot.md
@@ -500,6 +500,7 @@ Then we edit `rc.conf`.
 
 ```
 rc_configured=YES
+critical_filesystems_local="OPTIONAL:/var OPTIONAL:/usr"
 
 # Add local overrides below.
 dhcpcd=YES