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Kubernetes Commands

Helper setup to edit .yaml files with Vim:

• VIM Setup for Yaml files

List of general purpose commands for Kubernetes management:

• PODS
• Create Deployments

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Best Practices for Azure Redis

Below are a set of best practices that I recommend for most customers. This information is based on my experience helping hundreds of Azure Redis customers investigate various issues.

Configuration and Concepts

1. Use Standard or Premium Tier for Production systems. The Basic Tier is a single node system with no data replication and no SLA. Also, use at least a C1 cache. C0 caches are really meant for simple dev/test scenarios since they have a shared CPU core, very little memory, are prone to "noisy neighbor", etc.
2. Remember that Redis is an In-Memory data store. Read this article so that you are aware of scenarios where data loss can occur.
3. Configure your client library to use a "connect timeout" of at least 10 to 15 seconds, giving the system time to connect even under higher CPU conditions. If your client or server tend to be under high load

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1. Install NFS on Server

Install the required packages (Ubuntu 12.04):

apt-get install nfs-kernel-server portmap

2. Share NFS Folder

Open the exports file:

vim /etc/exports

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-- show running queries (pre 9.2)
SELECT procpid, age(query_start, clock_timestamp()), usename, current_query 
FROM pg_stat_activity 
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' 
ORDER BY query_start desc;

-- show running queries (9.2)
SELECT pid, age(query_start, clock_timestamp()), usename, query 
FROM pg_stat_activity 
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' 

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from impacket import smb
from struct import pack
import sys

'''
PoC for trigger EternalBlue bug (BSOD)

Reference:
- http://blogs.360.cn/360safe/2017/04/17/nsa-eternalblue-smb/
'''

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#!/usr/bin/env sh
## update.sh - manage a OpenWRT LetsEncrypt https instalation
# HOWTO: 
# - put update.sh in its own directory (like /root/.https)
# - run ./update.sh your.domain.com (that domain needs to point to your router)
#  * this get an issued cert from letsencrypt.org using the webroot verification method
#  * also installs curl and ca-certificates packages
# - use crontab -e; add the line `0 0 * * * "/root/.https/update.sh" >>/root/.https/log.txt 2>&`
#  * this runs the update every day, logging everything to log.txt
#

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# write-ups

## Resources

- [shell-storm](http://shell-storm.org/repo/)

## Tutorials

- [Codebashing](http://www.codebashing.com/)

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Latency Comparison Numbers
--------------------------
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
Send 1K bytes over 1 Gbps network        10,000   ns    0.01 ms
Read 4K randomly from SSD*              150,000   ns    0.15 ms

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#!/usr/bin/env ruby 
require "date"

five_days_ago = Date.parse(Time.now.to_s) - 5
IO.popen("hadoop fs -lsr /tmp").each_line do |line|  
  permissions,replication,user,group,size,mod_date,mod_time,path = *line.split(/\s+/)
  if (mod_date)
    if Date.parse(mod_date.to_s) < five_days_ago
      puts line
      if permissions.split('')[0] == 'd'

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$ ./bin/spark-shell
14/04/18 15:23:49 INFO spark.HttpServer: Starting HTTP Server
14/04/18 15:23:49 INFO server.Server: jetty-7.x.y-SNAPSHOT
14/04/18 15:23:49 INFO server.AbstractConnector: Started [email protected]:49861
Welcome to
      ____              __
     / __/__  ___ _____/ /__
    _\ \/ _ \/ _ `/ __/  '_/
   /___/ .__/\_,_/_/ /_/\_\   version 0.9.1
      /_/