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@Manouchehri
Manouchehri / cloudflare.sh
Last active April 16, 2025 11:55
Allow CloudFlare only
# Source:
# https://www.cloudflare.com/ips
# https://support.cloudflare.com/hc/en-us/articles/200169166-How-do-I-whitelist-CloudFlare-s-IP-addresses-in-iptables-
for i in `curl https://www.cloudflare.com/ips-v4`; do iptables -I INPUT -p tcp -m multiport --dports http,https -s $i -j ACCEPT; done
for i in `curl https://www.cloudflare.com/ips-v6`; do ip6tables -I INPUT -p tcp -m multiport --dports http,https -s $i -j ACCEPT; done
# Avoid racking up billing/attacks
# WARNING: If you get attacked and CloudFlare drops you, your site(s) will be unreachable.
iptables -A INPUT -p tcp -m multiport --dports http,https -j DROP
@wen-long
wen-long / ss-redir 透明代理.md
Last active March 18, 2024 12:13
ss-redir 透明代理.md

##ss-redir 的 iptables 配置(透明代理)

透明代理指对客户端透明,客户端不需要进行任何设置就使用了网管设置的代理规则

创建 /etc/ss-redir.json 本地监听 7777 运行ss-redir -v -c /etc/ss-redir.json

iptables -t nat -N SHADOWSOCKS
# 在 nat 表中创建新链
iptables -t nat -A SHADOWSOCKS -p tcp --dport 23596 -j RETURN
# 23596 是 ss 代理服务器的端口,即远程 shadowsocks 服务器提供服务的端口,如果你有多个 ip 可用,但端口一致,就设置这个
@jboner
jboner / latency.txt
Last active April 19, 2025 04:40
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@pokstad
pokstad / rediswebpy.py
Created September 7, 2011 23:02
Redis session store backend for web.py
import redis
import web
SESSION = 'SESSION:'
class RedisStore(web.session.Store):
"""Store for saving a session in redis:
import rediswebpy
session = web.session.Session(app, rediswebpy.RedisStore(), initializer={'count': 0})