phylake

probe kernel.function("tcp_send_challenge_ack") {
    printf("tcp_send_challenge_ack local=%s:%d remote=%s:%d\n", 
        format_ipaddr(tcpmib_local_addr($sk), AF_INET),
        tcpmib_local_port($sk),
        format_ipaddr(tcpmib_remote_addr($sk), AF_INET),
        tcpmib_remote_port($sk)
    );
}

phylake

ifconfig | grep broadcast | arp -a

phylake

Internet Scale Services Checklist

A checklist for designing and developing internet scale services, inspired by James Hamilton's 2007 paper "On Desgining and Deploying Internet-Scale Services."

• http://mvdirona.com/jrh/talksandpapers/jamesrh_lisa.pdf

Basic tenets

• Does the design expect failures to happen regularly and handle them gracefully?
• Have we kept things as simple as possible?

phylake

*     text=auto
*.bat text eol=crlf

phylake

wget http://packages.erlang-solutions.com/erlang-solutions_1.0_all.deb
sudo dpkg -i erlang-solutions_1.0_all.deb
sudo apt-get update
sudo apt-get install -y erlang

phylake

# forward local port 8080 to remotehost.com:3001
ssh -L 8080:localhost:3001 -N user@remotehost.com

phylake

module Main where

class A a where
class B a where

foo :: (A a, B b) => IO a -> (a -> IO b) -> IO ()
foo _ func = return ()
    where
        -- this breaks because func is not passed in
        barBroken :: (A a, B b) => a -> IO b

phylake

-- warp-2.1.5.2
-- ghc -O2 -threaded -rtsopts warp
-- ./warp +RTS -N -A1G
{-# LANGUAGE OverloadedStrings #-}
module Main where

import           Blaze.ByteString.Builder (copyByteString)
import           Data.Text (unpack)
import           Network.HTTP.Types.Status (status200)
import           Network.Wai

phylake

Sample service script for debianoids

Look at LSB init scripts for more information.

Usage

Copy to /etc/init.d:

# replace "$YOUR_SERVICE_NAME" with your service's name (whenever it's not enough obvious)

phylake

#!/bin/bash
# LC_CTYPE is for darwin
cat /dev/urandom | LC_CTYPE=C tr -cd 'a-f0-9' | head -c 32