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@bill-long
bill-long / CheckAllDCsForGuid.ps1
Created February 10, 2016 20:53
Check every GC and DC for a specific objectGUID
$guid = "bc87047d-25e8-11d3-9079-00805f31f826"
$gcs = [System.DirectoryServices.ActiveDirectory.Forest]::GetCurrentForest().GlobalCatalogs
$gcs | % {
$entry = [ADSI]("GC://" + $_.Name + "/<GUID=" + $guid + ">")
if ($entry.Guid -ne $null)
{
$entry
}
else
@frengky
frengky / firewalld.md
Last active December 27, 2022 17:28
FirewallD command line snippets for Linux

FirewallD command line snippets for Linux

Create new zone identified by an IP Address or interface This 'example' zone rules will applied to the connection from 192.168.1.2

  $ firewall-cmd --list-all-zones
  $ firewall-cmd --permanent --new-zone=example
  $ firewall-cmd --permanent --zone=example --add-source=192.168.1.2
  $ firewall-cmd --zone=example --list-sources
@joewiz
joewiz / post-mortem.md
Last active October 16, 2024 07:39
Recovery from nginx "Too many open files" error on Amazon AWS Linux

On Tue Oct 27, 2015, history.state.gov began buckling under load, intermittently issuing 500 errors. Nginx's error log was sprinkled with the following errors:

2015/10/27 21:48:36 [crit] 2475#0: accept4() failed (24: Too many open files)

2015/10/27 21:48:36 [alert] 2475#0: *7163915 socket() failed (24: Too many open files) while connecting to upstream...

An article at http://www.cyberciti.biz/faq/linux-unix-nginx-too-many-open-files/ provided directions that mostly worked. Below are the steps we followed. The steps that diverged from the article's directions are marked with an *.

  1. * Instead of using su to run ulimit on the nginx account, use ps aux | grep nginx to locate nginx's process IDs. Then query each process's file handle limits using cat /proc/pid/limits (where pid is the process id retrieved from ps). (Note: sudo may be necessary on your system for the cat command here, depending on your system.)
  2. Added fs.file-max = 70000 to /etc/sysctl.conf

An Ansible summary

Patterns

  • all (or *)
  • hostname: foo.example.com
  • groupname: webservers
  • or: webservers:dbserver
  • exclude: webserver:!phoenix
  • intersection: webservers:&amp;staging
@vongosling
vongosling / gist:9929680
Last active April 9, 2025 18:30
Performance Tuning

Three system configuration parameters must be set to support a large number of open files and TCP connections with large bursts of messages. Changes can be made using the /etc/rc.d/rc.local or /etc/sysctl.conf script to preserve changes after reboot.

1. /proc/sys/fs/file-max: The maximum number of concurrently open files.

fs.file-max = 1000000

2. /proc/sys/net/ipv4/tcp_max_syn_backlog: Maximum number of remembered connection requests, which are still did not receive an acknowledgment from connecting client. The default value is 1024 for systems with more than 128Mb of memory, and 128 for low memory machines.

net.ipv4.tcp_max_syn_backlog = 3240000

3. /proc/sys/net/core/somaxconn: Limit of socket listen() backlog, known in userspace as SOMAXCONN. Defaults to 128.

net.core.somaxconn = 3240000

@roundand
roundand / OpenWithSublimeText3.bat
Last active January 30, 2025 13:12 — forked from mrchief/LICENSE.md
Open folders and files with Sublime Text 3 from windows explorer context menu (tested in Windows 7)
@echo off
SET st3Path=C:\Program Files\Sublime Text 3\sublime_text.exe
rem add it for all file types
@reg add "HKEY_CLASSES_ROOT\*\shell\Open with Sublime Text 3" /t REG_SZ /v "" /d "Open with Sublime Text 3" /f
@reg add "HKEY_CLASSES_ROOT\*\shell\Open with Sublime Text 3" /t REG_EXPAND_SZ /v "Icon" /d "%st3Path%,0" /f
@reg add "HKEY_CLASSES_ROOT\*\shell\Open with Sublime Text 3\command" /t REG_SZ /v "" /d "%st3Path% \"%%1\"" /f
rem add it for folders
@reg add "HKEY_CLASSES_ROOT\Folder\shell\Open with Sublime Text 3" /t REG_SZ /v "" /d "Open with Sublime Text 3" /f
@mustafaturan
mustafaturan / latest-ffmpeg-centos6.sh
Last active October 25, 2022 20:14
Installs latest ffmpeg on Centos 6
# source: https://trac.ffmpeg.org/wiki/CentosCompilationGuide
yum install autoconf automake gcc gcc-c++ git libtool make nasm pkgconfig zlib-devel
mkdir ~/ffmpeg_sources
cd ~/ffmpeg_sources
curl -O http://www.tortall.net/projects/yasm/releases/yasm-1.2.0.tar.gz
tar xzvf yasm-1.2.0.tar.gz
cd yasm-1.2.0
@danielestevez
danielestevez / gist:2044589
Last active April 13, 2025 23:35
GIT Commit to an existing Tag
1) Create a branch with the tag
git branch {tagname}-branch {tagname}
git checkout {tagname}-branch
2) Include the fix manually if it's just a change ....
git add .
git ci -m "Fix included"
or cherry-pick the commit, whatever is easier
git cherry-pick {num_commit}