From 2b2c45df65110e3f768cb31651f4f3528f1da138 Mon Sep 17 00:00:00 2001
From: light <1870499383@qq.com>
Date: Mon, 1 Jan 2018 18:06:22 +0800
Subject: [PATCH] 2018

---
 ngrok/ngrok.md                |  7 +++----
 python/virtualenv.md          |  2 +-
 raspberry/main.md             | 15 +++++++++++++++
 ubuntu/aria2.md               |  8 ++++++++
 ubuntu/iptables.md            | 36 +++++++++++++++++++++++++++++++++++
 ubuntu/update-alternatives.md |  8 ++++++++
 6 files changed, 71 insertions(+), 5 deletions(-)
 create mode 100644 raspberry/main.md
 create mode 100644 ubuntu/aria2.md
 create mode 100644 ubuntu/iptables.md
 create mode 100644 ubuntu/update-alternatives.md

diff --git a/ngrok/ngrok.md b/ngrok/ngrok.md
index 7b9cfc5..3c40b41 100644
--- a/ngrok/ngrok.md
+++ b/ngrok/ngrok.md
@@ -29,16 +29,15 @@ sudo make release-server release-client
 ```
 
 ``` bash
-sudo ./bin/ngrokd -tlsKey=server.key -tlsCrt=server.crt -domain="ngrok.hellolight.me" -httpAddr=":8081" -httpsAddr=":8082" 
+# 服务器上运行服务命令
+sudo ./bin/ngrokd -tlsKey=server.key -tlsCrt=server.crt -domain="ngrok.hellolight.me" -httpAddr=":8081" -httpsAddr=":8082"
 ```
 
-
 ``` bash
 server_addr: "ngrok.hellolight.me:4443"
 trust_host_root_certs: false
 ```
+
 ./ngrok -subdomain pub -proto=http -config=ngrok.cfg 8000
 
 ./ngrok -subdomain pub -proto=http -config=ngrok.cfg 22
-
-
diff --git a/python/virtualenv.md b/python/virtualenv.md
index 86dfab3..b2840d5 100644
--- a/python/virtualenv.md
+++ b/python/virtualenv.md
@@ -3,4 +3,4 @@
 
 > virtualenv -p /usr/bin/python3 --system-site-packages venv
 
-> virtualenv -p /usr/bin/python2 --no-site-packages venv
\ No newline at end of file
+> virtualenv -p /usr/bin/python2 --no-site-packages venv
diff --git a/raspberry/main.md b/raspberry/main.md
new file mode 100644
index 0000000..fe68a15
--- /dev/null
+++ b/raspberry/main.md
@@ -0,0 +1,15 @@
+# 树莓派安装使用
+
+## linux下 安装
+
+``` bash
+df -h # 查看已有硬盘
+# 插入sd卡
+df -h # 查看新增磁盘
+fdisk /dev/sdx  # 删除增加分区
+
+dd bs=4M if=2017-11-29-raspbian-stretch.img of=/dev/sdX     # 写入镜像
+
+sudo watch -n 5 pkill -USR1 ^dd$    # 查看dd进程
+
+```
diff --git a/ubuntu/aria2.md b/ubuntu/aria2.md
new file mode 100644
index 0000000..e97e37b
--- /dev/null
+++ b/ubuntu/aria2.md
@@ -0,0 +1,8 @@
+# ubuntu 下安装使用 aria2
+
+- http://blog.csdn.net/crazycui/article/details/52205908
+
+## 安装
+
+> sudo apt install aria2
+
diff --git a/ubuntu/iptables.md b/ubuntu/iptables.md
new file mode 100644
index 0000000..55e96ed
--- /dev/null
+++ b/ubuntu/iptables.md
@@ -0,0 +1,36 @@
+# linux 下使用iptables 做路由转发
+
+- 参考自 http://blog.csdn.net/whatday/article/details/53634954
+
+## 环境
+
+    两台设备：
+        ubuntu 16.04
+            eth0    192.168.1.2/24      192.168.1.2
+            wlan0   10.138.177.83       *.*.*.*
+        raspberry pi b+
+            eth0    192.168.1.10/24     192.168.1.2
+
+## iptables 命令
+
+参考自 http://man.linuxde.net/iptables
+
+``` bash
+iptables -t 表名 <-A/I/D/R> 规则链名 [规则号] <-i/o 网卡名> -p 协议名 <-s 源IP/源子网> --sport 源端口 <-d 目标IP/目标子网> --dport 目标端口 -j 动作
+
+```
+
+## 设置静态ip
+
+> sudo nano /etc/network/interfaces
+
+``` bash
+auto eth0
+iface eth0 inet static
+address 192.168.8.100
+netmask 255.255.255.0
+gateway 192.168.8.2
+dns-nameserver 119.29.29.29
+```
+
+> sudo /etc/init.d/networking restart # 重启网络
\ No newline at end of file
diff --git a/ubuntu/update-alternatives.md b/ubuntu/update-alternatives.md
new file mode 100644
index 0000000..8568d01
--- /dev/null
+++ b/ubuntu/update-alternatives.md
@@ -0,0 +1,8 @@
+# update-alternatives
+
+``` bash
+# 设置优先级
+sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.8 20
+# 查询版本
+sudo update-alternatives --query gcc
+```
\ No newline at end of file