Update build_nat_network.sh

scripts/build_nat_network.sh

@@ -1,7 +1,7 @@
 #!/bin/bash
 # from 
 # https://github.com/spiritLHLS/pve
-# 2023.08.17
+# 2023.08.20
 
 
 ########## 预设部分输出和部分中间变量
@@ -199,11 +199,34 @@ else
 fi
 ${sysctl_path} -p
 
+# 删除可能存在的原有的网卡配置
+cp /etc/network/interfaces /etc/network/interfaces_nat.bak
+chattr -i /etc/network/interfaces
+input_file="/etc/network/interfaces"
+output_file="/etc/network/interfaces.tmp"
+start_pattern="iface lo inet loopback"
+end_pattern="auto vmbr0"
+delete_lines=0
+while IFS= read -r line; do
+    if [[ $line == *"$start_pattern"* ]]; then
+        delete_lines=1
+    fi
+    if [ $delete_lines -eq 0 ]; then
+        echo "$line" >> "$output_file"
+    fi
+    if [[ $line == *"$end_pattern"* ]]; then
+        delete_lines=0
+    fi
+done < "$input_file"
+mv "$output_file" "$input_file"
+chattr +i /etc/network/interfaces
+
 # 重启配置
 service networking restart
 systemctl restart networking.service
 sleep 3
 ifreload -ad
+iptables-save | awk '{if($1=="COMMIT"){delete x}}$1=="-A"?!x[$0]++:1' | iptables-restore
 # 已加载网络，删除对应缓存文件
 if [ -f "/etc/network/interfaces.new" ];then
     chattr -i /etc/network/interfaces.new