Linux系统TCP/IP网络编程配置指南

基本系统配置

1. 检查网络接口配置

# 查看网络接口信息
ifconfig -a
ip addr show

# 检查路由表
route -n
ip route show

2. 确保网络服务正常运行

# 检查网络服务状态(根据发行版选择)
systemctl status networking  # Debian/Ubuntu
systemctl status network     # RHEL/CentOS

开发环境配置

1. 安装必要开发工具

# 安装GCC编译器
sudo apt-get install build-essential  # Debian/Ubuntu
sudo yum groupinstall "Development Tools"  # RHEL/CentOS

# 安装网络调试工具
sudo apt-get install net-tools tcpdump wireshark  # Debian/Ubuntu
sudo yum install net-tools tcpdump wireshark      # RHEL/CentOS

2. 配置防火墙(如果需要)

# 临时开放端口(重启后失效)
sudo iptables -A INPUT -p tcp --dport [PORT] -j ACCEPT

# 永久保存iptables规则(根据发行版选择)
sudo apt-get install iptables-persistent  # Debian/Ubuntu
sudo service iptables save               # RHEL/CentOS 6
sudo firewall-cmd --add-port=[PORT]/tcp --permanent  # RHEL/CentOS 7+ firewalld
sudo firewall-cmd --reload

网络编程相关配置

1. 系统参数调优

# 查看当前TCP/IP参数
sysctl -a | grep net.ipv4

# 常用调优参数(编辑/etc/sysctl.conf)
net.ipv4.tcp_fin_timeout = 30
net.ipv4.tcp_keepalive_time = 1200
net.ipv4.tcp_max_syn_backlog = 8192
net.ipv4.tcp_max_tw_buckets = 5000
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
net.ipv4.ip_local_port_range = 1024 65535

# 应用修改
sudo sysctl -p

2. 文件描述符限制

# 查看当前限制
ulimit -n

# 修改限制(编辑/etc/security/limits.conf)
* soft nofile 65535
* hard nofile 65535

# 需要重新登录生效

测试网络编程环境

1. 简单TCP服务器测试

// 保存为server.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <netinet/in.h>

#define PORT 8080
#define BUFFER_SIZE 1024

int main() {
    int server_fd, new_socket;
    struct sockaddr_in address;
    int opt = 1;
    int addrlen = sizeof(address);
    char buffer[BUFFER_SIZE] = {0};

    // 创建socket
    if ((server_fd = socket(AF_INET, SOCK_STREAM, 0)) == 0) {
        perror("socket failed");
        exit(EXIT_FAILURE);
    }

    // 设置socket选项
    if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR | SO_REUSEPORT, &opt, sizeof(opt))) {
        perror("setsockopt");
        exit(EXIT_FAILURE);
    }

    address.sin_family = AF_INET;
    address.sin_addr.s_addr = INADDR_ANY;
    address.sin_port = htons(PORT);

    // 绑定socket
    if (bind(server_fd, (struct sockaddr *)&address, sizeof(address)) < 0) {
        perror("bind failed");
        exit(EXIT_FAILURE);
    }

    // 监听
    if (listen(server_fd, 3) < 0) {
        perror("listen");
        exit(EXIT_FAILURE);
    }

    printf("Server listening on port %d...\n", PORT);

    // 接受连接
    if ((new_socket = accept(server_fd, (struct sockaddr *)&address, (socklen_t*)&addrlen)) < 0) {
        perror("accept");
        exit(EXIT_FAILURE);
    }

    // 读取数据
    read(new_socket, buffer, BUFFER_SIZE);
    printf("Message received: %s\n", buffer);

    // 发送响应
    char *response = "Hello from server";
    send(new_socket, response, strlen(response), 0);
    printf("Response sent\n");

    return 0;
}

2. 编译并运行测试

# 编译服务器
gcc server.c -o server

# 运行服务器(需要root权限绑定低端口)
sudo ./server

# 在另一个终端测试连接
telnet localhost 8080
# 或使用netcat
nc localhost 8080

高级配置(可选)

1. 启用IPv6支持

# 检查IPv6支持
cat /proc/sys/net/ipv6/conf/all/disable_ipv6  # 0表示启用

# 启用IPv6(如果未启用)
echo 0 | sudo tee /proc/sys/net/ipv6/conf/all/disable_ipv6

# 永久启用(编辑/etc/sysctl.conf)
net.ipv6.conf.all.disable_ipv6 = 0

2. 安装高性能网络库

# 安装libevent
sudo apt-get install libevent-dev  # Debian/Ubuntu
sudo yum install libevent-devel    # RHEL/CentOS

# 安装ZeroMQ
sudo apt-get install libzmq3-dev   # Debian/Ubuntu
sudo yum install zeromq-devel      # RHEL/CentOS

通过以上配置，您的Linux系统将能够很好地支持TCP/IP网络编程开发。根据具体应用需求，可能还需要进一步调整系统参数或安装特定库。