next.js 踩坑笔记

1、nginx转发：

location / {
    proxy_pass http://localhost:3000;
    proxy_http_version 1.1;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection 'upgrade';
    proxy_set_header Host $host;
    proxy_cache_bypass $http_upgrade;
}
复制代码

2、页面引用/_next/...和输出目录/.next/...不一致问题，修改构建输出目录：

// next.config.js
module.export = {
    distDir: '_next'
}
复制代码

3、字体文件加载 next-plugins：

npm install next-fonts

// next.config.js
const withFonts = require('next-fonts');
module.export = withFonts({
    ...
});
复制代码

4、异步加载的js，全局变量需要加判断，否则会闪一下错误信息，例如Google Analytics：

<script async src="https://www.googletagmanager.com/gtag/js"></script>

if (typeof gtag !== "undefined"){
    gtag("event", name, {event_category: category});
}
复制代码

5、Linux系统open files 1024限制导致too many open files错误

修改 /etc/security/limits.conf

* soft nofile 1000000
* hard nofile 1000000

* soft nproc 1000000
* hard nproc 1000000
复制代码

保存后重新登录，执行 ulimit -a 查看是否生效

6、nginx负载均衡

upstream yourname {
    least_conn;
    server 127.0.0.1:3006;
    server 127.0.0.1:3007;
    server 127.0.0.1:3008;
    # 该connections参数设置在每个工作进程的缓存中保留的上游服务器的最大空闲keepalive连接数。超过此数量时，将关闭最近最少使用的连接。
    # 应特别注意的是，该keepalive指令不限制nginx工作进程可以打开的上游服务器的连接总数。该connections参数应设置为足够小的数字，以允许上游服务器处理新的传入连接。
    keepalive 3;
    # nginx的长链接是等超时以后才会断开，如果超时时间过长，机器会因为TCP链接耗尽崩溃出现EBUSY错误
    keepalive_timeout 5; 
}

server {
    location / {
        proxy_pass http://yourname;
        add_header backend_ip $upstream_addr;  #方便查看请求被转发到哪个地址
        add_header backend_code $upstream_status;
    }
}
复制代码

7、优化Linux系统配置，提高并发能力

修改 /etc/sysctl.conf, 执行 sysctl -p 生效

# 避免放大攻击
net.ipv4.icmp_echo_ignore_broadcasts = 1

# 开启恶意icmp错误消息保护
net.ipv4.icmp_ignore_bogus_error_responses = 1

# SYN洪水攻击保护，高并发建议关闭
net.ipv4.tcp_syncookies = 0

# 重试次数
net.ipv4.tcp_syn_retries = 1
net.ipv4.tcp_synack_retries = 1

# 开启并记录欺骗，源路由和重定向包
net.ipv4.conf.all.log_martians = 1
net.ipv4.conf.default.log_martians = 1

# 处理无源路由的包
net.ipv4.conf.all.accept_source_route = 0
net.ipv4.conf.default.accept_source_route = 0

# 开启反向路径过滤
net.ipv4.conf.all.rp_filter = 1
net.ipv4.conf.default.rp_filter = 1

# 禁用重定向包
net.ipv4.conf.all.accept_redirects = 0
net.ipv4.conf.default.accept_redirects = 0
net.ipv4.conf.all.secure_redirects = 0
net.ipv4.conf.default.secure_redirects = 0

# 不充当路由器
net.ipv4.ip_forward = 0
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.default.send_redirects = 0

# 开启execshild
kernel.exec-shield = 1
kernel.randomize_va_space = 1

# IPv6设置
net.ipv6.conf.default.router_solicitations = 0
net.ipv6.conf.default.accept_ra_rtr_pref = 0
net.ipv6.conf.default.accept_ra_pinfo = 0
net.ipv6.conf.default.accept_ra_defrtr = 0
net.ipv6.conf.default.autoconf = 0
net.ipv6.conf.default.dad_transmits = 0
net.ipv6.conf.default.max_addresses = 1

# 增加系统文件描述符限制
fs.file-max = 1000000
fs.nr_open = 1000000

# 允许更多的PIDs (减少滚动翻转问题); may break some programs 32768
kernel.pid_max = 65536

# 增加系统IP端口限制
net.ipv4.ip_local_port_range = 3000 65535

# 增加TCP最大缓冲区大小
# 增加Linux自动调整TCP缓冲区限制
# 最小，默认和最大可使用的字节数
# 最大值不低于4MB，如果你使用非常高的BDP路径可以设置得更高
net.ipv4.tcp_rmem = 4096 87380 8388608
net.ipv4.tcp_wmem = 4096 87380 8388608

# Tcp窗口等
net.core.rmem_max = 8388608
net.core.wmem_max = 8388608
net.core.netdev_max_backlog = 1000000
net.ipv4.tcp_max_syn_backlog = 1000000
net.core.somaxconn = 1000000
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_max_tw_buckets = 1000000
net.ipv4.tcp_max_orphans = 1000000

# 开启重用，将TIME_WAIT的socket重新用于连接
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_timestamps = 0

# 开启TCP连接中TIME_WAIT的socket快速回收
net.ipv4.tcp_tw_recycle = 1

# 修改系统默认的TIMEOUT时间
net.ipv4.tcp_fin_timeout = 10

# 减少TCP KeepAlive连接侦测的时间，可以使得服务器更快的侦测出异常退出的客户端连接。默认为7200s
net.ipv4.tcp_keepalive_time = 10
复制代码