arstercz

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start new:

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start new with session name:

tmux new -s myname

arstercz

Better SSH Authorized Keys Management

A seemingly common problem that people encounter is how to handle all of your users authorized_keys file.

People struggle over management, ensuring that users only have specific keys in the authorized_keys file or even a method for expiring keys. A centralized key management system could help provide all of this functionality with a little scripting.

One piece of functionality overlooked in OpenSSH is the AuthorizedKeysCommand configuration keyword. This configuration allows you to specify a command that will run during login to retrieve a users public key file from a remote source and perform validation just as if the authorized_keys file was local.

Here is an example directory structure for a set of users with SSH public keys that can be shared out via a web server:

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Steps to generate self-signed PKCS#12 SSL certificate and export its keys:

1- Create PKCS#12 keystore (.p12 or .pfx file)

keytool -genkeypair -keystore myKeystore.p12 -storetype PKCS12 -storepass MY_PASSWORD -alias KEYSTORE_ENTRY -keyalg RSA -keysize 2048 -validity 99999 -dname "CN=My SSL Certificate, OU=My Team, O=My Company, L=My City, ST=My State, C=SA" -ext san=dns:mydomain.com,dns:localhost,ip:127.0.0.1

• myKeystore.p12 = keystore filename. It can with .pfx extension as well.
• MY_PASSWORD = password used for the keystore and the private key as well.
• CN = commonName, it will be shown as certiciate name in certificates list.
• OU = organizationUnit, department name for example.

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    if ($request_uri = /) { 
      set $test  A; 
    } 
  
    if ($host ~* teambox.com) { 
      set $test  "${test}B"; 
    } 
  
    if ($http_cookie !~* "auth_token") { 
      set $test  "${test}C"; 

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Introduction

• C-a == Ctrl-a
• M-a == Alt-a

General

:q        close
:w        write/saves
:wa[!]    write/save all windows [force]
:wq       write/save and close

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Decoding the data in /proc/net/tcp:

Linux 5.x  /proc/net/tcp
Linux 6.x  /proc/PID/net/tcp

Given a socket:

$ ls -l  /proc/24784/fd/11
lrwx------ 1 jkstill dba 64 Dec  4 16:22 /proc/24784/fd/11 -> socket:[15907701]

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测试机器

   Centos 6/7
   Ubuntu 18.04/20.04
   Debian 10.6

如何安装

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#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>

#define NUM_LOOKUPS 1024

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# --------
# Hardware
# --------

# Opcode - operational code
# Assebly mnemonic - abbreviation for an operation

# Instruction Code Format (IA-32)
# - Optional instruction prefix
# - Operational code

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Redis best practices have moved

This content has been moved a new, happier home where it can serve more people. Please check it out : https://docs.microsoft.com/azure/azure-cache-for-redis/cache-best-practices.

Note that some of the content still lives here, but don't worry, it will be migrated over time.