diff --git a/README.md b/README.md
index 7bf67ed..6ef7300 100644
--- a/README.md
+++ b/README.md
@@ -10,7 +10,7 @@ This script is written to reinstall a VPS/virtual machine to Debian 10 Buster.
 
  * SolusVM/OpenStack/DigitalOcean/Vultr/Linode/Proxmox/QEMU KVM (BIOS boot)
  * Oracle Cloud Infrastructure (UEFI boot)
- * Google Cloud Compute Engine (**Must configure VPC internal IP and gateway manually**, UEFI boot, Secure Boot supported)
+ * Google Cloud Compute Engine (**Must manually configure VPC internal IP and gateway.** UEFI boot with Secure Boot support)
  * AWS EC2 & Lightsail (BIOS boot)
  * Hyper-V & Azure (Generation 1 BIOS boot & Generation 2 UEFI boot)
 
diff --git a/debi.sh b/debi.sh
index 045b788..a2d7389 100755
--- a/debi.sh
+++ b/debi.sh
@@ -32,9 +32,9 @@ in_target_backup() {
 }
 
 configure_sshd() {
-    # !isset($backup_sshd_config)
-    [ -z ${backup_sshd_config+1s} ] && in_target_backup /etc/ssh/sshd_config
-    backup_sshd_config=
+    # !isset($sshd_config_backup)
+    [ -z ${sshd_config_backup+1s} ] && in_target_backup /etc/ssh/sshd_config
+    sshd_config_backup=
     in_target sed -Ei \""s/^#?$1 .+/$1 $2/"\" /etc/ssh/sshd_config
 }