Linux utils

• Pi Roles

Utils

• Set date

sudo date --set "25 Sep 2013 15:00:00"

• check disks on ubuntu

sudo lsblk

• check that a node is pingable in bash

while ! ping -c1 bjjc_spec_22.ubuntu14 &>/dev/null; do :; done ;

• how to tell if port 80 is listening?

telnet?

• how do I know if the system trusts the certificate?

you use curl.

• how to tell if port 80 is listening? What is listening on a particular port?

netstat -plnt

Find large files

find / -xdev -type f -size +100M

see timestamp in history

echo 'export HISTTIMEFORMAT="%d/%m/%y %T "' >> ~/.bashrc ; source ~/.bashrc

Generate large random file

dd if=/dev/urandom of=/var/log/mongodb/randomFile bs=1M count=200

Add ssh key to a server

cat ~/.ssh/id_rsa.pub | ssh user@hostname 'cat >> .ssh/authorized_keys'

Create a user

su - <username>
sudo visudo -f /etc/sudoers
sudo adduser --disabled-password <username>
(and there is deluser)
(I don't think I need this: usermod -aG sudo username ) - for making him a sudoer

Nodes

This one, before I started sticking Node.js in there.

WARNING! in the codebase node listens on 3000. In production it listens on 3007.

piousbox@piousbox-laptop:~/projects/rails-quick-start$ knife node show app_server_21
Node Name:   app_server_21
Environment: _default
FQDN:        
IP:          10.0.1.151
Run List:    role[base], role[ish_static], role[marchesi_static], role[wiki_cac], role[wp_wasya]
Roles:       base, ish_static, marchesi_static, wiki_cac, wp_wasya
Recipes:     zsh, users::sysadmins, sudo, apt, nagios::client, git, build-essential, ish::base_apache, ish::static_site, ish_apache::static_site, ish_apache::base_apache, ish::base_php, mysql::client, mediawiki::default, mediawiki::appserver, wordpress::default
Platform:    ubuntu 12.04
Tags:      

This is a successful deployment except change node's listening from 3000 to 3007:

piousbox@piousbox-laptop:~/projects/rails-quick-start$ knife node show app_server_21
Node Name:   app_server_21
Environment: _default
FQDN:        
IP:          10.0.1.151
Run List:    role[base], role[node_exampler]
Roles:       base, node_exampler
Recipes:     zsh, users::sysadmins, sudo, apt, nagios::client, git, build-essential, node::base, node::upstream
Platform:    ubuntu 12.04
Tags:        

The load balancer:

ubuntu@ip-10-0-0-52:/etc/apache2/sites-available$ pwd
/etc/apache2/sites-available
ubuntu@ip-10-0-0-52:/etc/apache2/sites-available$ cat startups_staging

<VirtualHost *:80>
  ServerAdmin piousbox@gmail.com
  ServerName annesque.com
  KeepAlive On
  ProxyVia On
  ProxyPreserveHost On
  ServerAlias staging.annesque.com
  ServerAlias startups.piousbox.com
  ServerAlias staging.startups.piousbox.com
  ProxyPreserveHost On
  ProxyVia On
  <proxy>
    Order deny,allow
    Allow from all
  </proxy>
  ProxyPass /api/ http://10.0.1.151:3007/ connectiontimeout=15 timeout=45
  ProxyPassReverse /api/ http://10.0.1.151:3007/
  ProxyPass / http://10.0.1.72:3010/ connectiontimeout=15 timeout=45
  ProxyPassReverse / http://10.0.1.72:3010/
</VirtualHost>

Utils

Remember the virtual site for combining a node backend into some other service?

<VirtualHost *:3098>
  ServerAdmin piousbox@gmail.com
  ServerName localhost
  KeepAlive On
  ProxyVia On
  ProxyPreserveHost On
  <proxy>
    Order deny,allow
    Allow from all
  </proxy>
  ProxyPass /api/ http://localhost:3000/ connectiontimeout=15 timeout=45
  ProxyPassReverse /api/ http://localhost:3000/
  ProxyPass / http://localhost:8000/ connectiontimeout=15 timeout=45
  ProxyPassReverse / http://localhost:8000/
</VirtualHost>

Establish a simple ssh port forward

10.0.0.x is public, 10.0.1.x is private. Do:

sudo sysctl net.ipv4.ip_forward=1
sudo iptables -t nat -A PREROUTING -p tcp -d 10.0.0.229 --dport 2270 -j DNAT --to-destination 10.0.1.224:22
sudo iptables -t nat -A POSTROUTING -j MASQUERADE

Reset Chef UI Password

sudo -u opscode-pgsql  /opt/chef-server/embedded/bin/psql opscode_chef
update osc_users set hashed_password = '$2a$12$y31Wno2MKiGXS3FSgVg5UunKG48gJz0pRV//RMy1osDxVbrb0On4W' , salt ='$2a$12$y31Wno2MKiGXS3FSgVg5Uu' where username ='admin';

and login with user 'admin' and password 'password'.