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{{Depreciated|category=Ubuntu}}
== Initial Setup ==
== Initial Setup ==
Much of this section is ''borrowed'' from http://www.howtoforge.com/perfect-server-ubuntu8.04-lts and http://www.howtoforge.com/how-to-install-ubuntu8.04-with-software-raid1, they are well worth a read!
Much of this section is ''borrowed'' from http://www.howtoforge.com/perfect-server-ubuntu8.04-lts and http://www.howtoforge.com/how-to-install-ubuntu8.04-with-software-raid1, they are well worth a read!


This section will create a Ubuntu VM installed on one partition, software RAID'ed across two VMDK's (my ESX's storage isn't resilient, hence the software RAID across VMDK's on separate physical disks, if you've got resilient storage you should '''not''' use software RAID).
This section will create a Ubuntu VM installed on one partition, software RAID'ed across two VMDK's.  To explain, my ESX's storage originally wasn't resilient, hence the software RAID across VMDK's on separate physical disks, if you've got resilient storage you should probably wouldn't use software RAID. 
 
''However, once I'd bought a nice (SOHO) NAS, I moved one disk and VM config across to NAS, thinking I'd eventually ditch the software RAID.  Luckily I didn't get round to it, so when I managed to destroy my NAS (partly my fault), I could easily recover my VM's from where they left off by creating new ones and re-using the surviving VMDK file.  Therefore, unless you're running a truly enterprise class NAS, that's cost you £1k's to buy, and £1k's in yearly support I'd still recommend you software RAID your critical VM's (eg mail server) across two separate devices. The whole reason you have a home set-up is to ''play'', which inevitably means ''break''!''


=== Prepare Virtual Machine ===
=== Prepare Virtual Machine ===
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         address 192.168.1.150
         address 192.168.1.150
         netmask 255.255.255.0
         netmask 255.255.255.0
         network 192.168.1.1
         network 192.168.1.0
         broadcast 192.168.1.255
         broadcast 192.168.1.255
         gateway 192.168.1.1
         gateway 192.168.1.1
Line 104: Line 108:


==== Ubuntu 10.04.1 LTS ====
==== Ubuntu 10.04.1 LTS ====
# Install the build library files...  
VM Tools can be installed via two methods, neither of which is ideal...
* Using the normal VM Tools ''CD'' - requires additional library install and sometimes mounting the CDROM doesn't work too well.
* Using APT package manager - doesn't work quite as well as it could (upgrading VM Tools isn't supported), and support for this method is rumoured to be dropped in future releases
 
'''VM Tools ''CD'''''
# Install the build library files (not required for ESX v4.0 update 2 and later)...  
#* <code> apt-get install build-essential </code>
#* <code> apt-get install build-essential </code>
# Select "Install VM Tools" from the VI Client
# Select "Install VM Tools" from the VI Client
# Mount the VM Tools CD-ROM  
# Mount the VM Tools CD-ROM  
#* <code> mount /dev/sr0 cdrom </code>
#* <code> mount /dev/cdrom /media/cdrom/ </code>
# Copy to tmp directory
#** If <code>/media/cdrom/</code> doesn't exist, create with <code>mkdir /media/cdrom</code>
#* <code> cp /cdrom/VMwareTools-4.0.0-236512.tar.gz /tmp/ </code>
# Copy to tmp directory (version number below will vary)
#* <code> cp /media/cdrom/VMwareTools-4.0.0-236512.tar.gz /tmp/ </code>
# Unmount the CD-ROM, and move into tmp directory
# Unmount the CD-ROM, and move into tmp directory
#* <code> umount /cdrom/ </code>
#* <code> umount /media/cdrom/ </code>
#* <code> cd /tmp/ </code>
#* <code> cd /tmp/ </code>
# Uncompress and then move into the <code> vmware-tools-distrib </code> directory
# Uncompress and then move into the <code> vmware-tools-distrib </code> directory
#* <code> tar xzvf VMware*.gz </code>
#* <code> tar xzvf VMware*.gz </code>
#* <code> cd vmware-tools-distrib </code>
#* <code> cd vmware-tools-distrib </code>/
# Run the install script, and accept defaults
# Run the install script, and accept defaults
#* <code> ./vmware-install.pl  </code>
#* <code> ./vmware-install.pl  </code>
# Restart
# Restart
#* <code> shutdown -r now </code>
#* <code> shutdown -r now </code>
'''APT Package Manager'''
# Install VM Tools using apt package manager
# Open VMware Packaging Public GPG Key at http://packages.vmware.com/tools/VMWARE-PACKAGING-GPG-KEY.pub
# On the server open a new file called <code>VMWARE-PACKAGING-GPG-KEY.pub</code> with the <code>/tmp</code> directory
# Copy and paste the contents of the webpage into the file and save
# Import the key using the following command
#* <code>apt-key add /tmp/VMWARE-PACKAGING-GPG-KEY.pub</code>
#* You should get <code>OK</code> returned
# If you need to add a proxy see http://communities.vmware.com/servlet/JiveServlet/download/1554533-39836/Vmware%20Tools%20Guide%20Linux%20osp_install_guide.pdf
# Open a new vi in VI called <code>/etc/apt/sources.list.d/vmware-tools.list</code>
# Add the following line
#* <code> deb http://packages.vmware.com/tools/esx/<esx-version>/ubuntu lucid main restricted </code> where <esx-version> is the appropriate esx version found at http://packages.vmware.com/tools/esx/index.html
# Update the repository cacahe
#* <code> apt-get update </code>
# Install VM Tools
#* <code> apt-get install vmware-tools </code>
=== NTP ===
''Not required if your server doesn't really need bang on accurate time''
Out of the box your server will sync every time its restarted and drift a bit in-between.  There is an additional resource demand in running the NTP daemon so unless you need to, there's no need to install the full blown NTP daemon.
I tend to have one or two servers updating from remote (public) servers, and then all others updating from those.
# Install the service
#* <code> apt-get install ntp </code>
# Update the NTP config file, <code> /etc/ntp.conf </code> (Example below is for a server updating from public European servers - see http://www.pool.ntp.org/)
#* <code> server 0.europe.pool.ntp.org </code>
#* <code> server 1.europe.pool.ntp.org </code>
#* <code> server 2.europe.pool.ntp.org </code>
#* <code> server 3.europe.pool.ntp.org </code>
# Restart the NTP service
#* <code> service ntp restart </code>
# Verify using the following commands
#* <code> ntpq -np </code>
#* <code> date </code>


=== Update the OS ===  
=== Update the OS ===  
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== Random Settings ==
== Random Settings ==
=== Locale ===
To change the local '''time-zone''' use...
* <code> dpkg-reconfigure tzdata </code>
To change the keyboard layout in use...
* <code> dpkg-reconfigure console-data </code>
...if <code> console-data </code> isn't installed, use...
* <code> apt-get install console-data </code>
...and reboot to apply
=== <code>\tmp</code> Boot Time Clean-up ===
=== <code>\tmp</code> Boot Time Clean-up ===
The files in <code>/tmp</code> get deleted if their last modification time is more than <code>TMPTIME</code> days ago.
The files in <code>/tmp</code> get deleted if their last modification time is more than <code>TMPTIME</code> days ago.


# Edit <code> /etc/default/rcS </code>
# Edit <code> /etc/default/rcS </code>
# Change <code>TMPTIME</code> value to specify no of days
# Change <code>TMPTI80aM80E</code> value to specify no of days
#* Use <code> 0 </code> so that files are removed regardless of age.
#* Use <code> 0 </code> so that files are removed regardless of age.
#* Use <code> -1 </code> so that no files are removed.
#* Use <code> -1 </code> so that no files are removed.
=== Proxy Server ===
Proxy settings need to be added as environment variables, which can be added to to your profile file so as to be always be applied
# Edit <code> /etc/profile </code>
# Append to the bottom (edit as required)
#* <code> export http_proxy=http://username:pass@proxyserver:port/ </code>
#* <code> export ftp_proxy=http://username:pass@proxyserver:port/ </code>
Note that some applications will ignore the environment variables, and will need to be set specifically for those apps.
=== Hostname Change ===
Procedure below guides you through the files etc that need updating in order to change a machine's hostname.  Note that if you get probs SSH'ing to the server afterwards see [[#Server_Hostname_Change|Server Hostname Change]]
# Update the following files
#* <code> /etc/hosts </code>
#* <code> /etc/hostname  </code>
# Set the hostname (not FQDN)
#* <code> hostname <servername> </code>
# Reboot
=== Allow Remote SSH Login Without Password Prompt ===
In order to be able to access a remote server via an SSH session without needing to suppy a password, the remote server needs to trust the user on the local server.  In order to do this, the public key for the user needs to be imported to the remote server.  This is particularly useful when trying to script using ssh, scp, rsync, etc where you need to interract with a remote server.
You need to be clear on which user will access the remote the server, if your script is run as root, then its the root user that needs to have its public key exported.
Similarly, on the remote server you need to ensure that that the user that has the public key key imported into, has the rights to perform whatever it is that you want to achieve.  This ''shouldn't'' be the root user (to do so you'd need to allow <code>PermitRootLogin </code> in the remote server's SSH config, which is a security no-no).
# On the local server, create a public/private rsa key pair while logged in as the user that will access the remote server
#* <code> ssh-keygen -t rsa </code> (leave passphrase blank)
#** This creates a public key in <code> ~/.ssh/id_rsa.pub </code>
# Copy the public key to the user on the remote server
#* <code> ssh-copy-id -i user@remote-svr </code>
#** The <code> user </code> is the user account on the remote server that the local server will be trusted by and run as.
# Test the login as suggested by <code> ssh-copy-id </code>
#* <code> ssh user@remote-svr </code>
== Packages ==
=== Commands ===
{|class="vwikitable"
|-
! Command                              !! Purpose
|-
| <code> dpkg --get-selections </code> || Show installed packages
|-
| <code> dpkg -L php5-gd </code>      || Show file locations of <code> php5-gd </code> package
|-
| <code> apt-get update </code>        || Update the package database
|-
| <code> apt-get install <package> </code>  || Install the <code> <package> </code> package
|-
| <code> apt-get upgrade </code>      || Upgrade installed system and packages with latest levels in package database
|-
| <code> tasksel install <task> </code> || Installs a collection of packages as a single task, eg lamp-server
|-
| <code> tasksel --list-task </code>  || Show list of available tasks
|}
=== Troubleshooting ===
* '''Error 400 Bad Request'''
** Somewhat misleadingly, the problem is normal caused by being unable to contact the update server.  Consider adding proxy server config to your machine
* '''The following packages have been kept back'''
** Package manager can hold back updates because they will cause conflicts, or sometimes because they're major kernel updates.  Running <code>aptitude upgrade</code> normally seems to force kernel updates through.
== Firewall ==
Ubuntu comes with UFW (Uncomplicated Firewall), which is a config tool used to modify the standard inbuilt Netfilter.  If preferred, iptables can still be used.
Changes are applied immediately. Once you've added your first rule there's an implied deny all.
{|class="vwikitable"
|-
! Command                              !! Purpose
|-
| <code> ufw enable </code>            || Enables the firewall
|-
| <code> ufw status </code>            || Shows the firewall status and existing filters
|-
| <code> ufw status numbered </code>    || Shows the firewall status and numbered existing filters (easier to delete)
|-
| <code> ufw allow from 192.168.1.10 </code> || Allow all traffic from 192.168.1.10
|-
| <code> ufw allow http </code>        || Allow http from any IP
|-
| <code> ufw allow proto tcp from 192.168.1.10 to any port 22 </code> || Allow TCP 22 (SSH) from 192.168.1.10
|-
| <code> ufw delete 2 </code>          || Delete rule 2
|}
So, for example, to create a couple of rules and enable...
ufw allow proto tcp from 192.168.10.0/24 to any port 22
ufw allow proto tcp to any port 443
ufw enable


== SNMP ==
== SNMP ==
Be aware that SNMP may already be installed on your system, but not in the default place, for example it can be installed with Zimbra, in which case the config file can be found in a different place (eg <code> /opt/zimbra/snmp/conf/snmp.conf </code>.  If there's an existing snmpd service running, its unlikely you'll want to install a second!
=== Setup (Pre v10) ===
 
=== Setup ===
# Run the following command to update the package database
# Run the following command to update the package database
#* <code> apt-get update </code>
#* <code> apt-get update </code>
# Run the following command to install SNMP
# Run the following command to install SNMP
#* <code> apt-get install snmpd </code>
#* <code> apt-get install snmpd </code>
# Create config file with contents as below
# Create config file with contents as shown below
#* <code> vi /etc/snmp/snmp.conf </code>
#* <code> vi /etc/snmp/snmpd.conf </code>
# Edit SNMPD config to allow remote polls
# Edit SNMPD config to allow remote polls
#* <code> vi /etc/default/snmpd </code>
#* <code> vi /etc/default/snmpd </code>
Line 158: Line 305:


  rocommunity public
  rocommunity public
syslocation "CR DC"
syscontact info@sandfordit.com
=== Setup (v10) ===
# Run the following command to update the package database
#* <code> apt-get update </code>
# Run the following command to install SNMP
#* <code> apt-get install snmpd </code>
# Create config file with contents as shown below the procedure
#* <code> vi /etc/snmp/snmpd.conf </code>
# Edit SNMPD config to allow remote polls
#* <code> vi /etc/default/snmpd </code>
# Remove <code> 127.0.0.1 </code> from line below
#* <code> <nowiki>#</nowiki>snmpd options (use syslog, close stdin/out/err). </code>
#* <code> SNMPDOPTS='-Lsd -Lf /dev/null -u snmp -I -smux -p /var/run/snmpd.pid 127.0.0.1' </code>
# Restart SNMP
#* <code> /etc/init.d/snmpd restart </code>
# Test with the following, replacing <hostname> with server's hostname (must be run from a machine with snmp installed, not just snmpd)
#* <code> snmpwalk -v 1 -c public <hostname> system <hostname> </code>
####
# First, map the community name (COMMUNITY) into a security name
# (local and mynetwork, depending on where the request is coming
# from):
#      sec.name  source          community
#com2sec paranoid  default        public '''<- Comment'''
com2sec readonly  default        public '''<- Uncomment'''
'''... then later ...'''
  syslocation "CR DC"
  syslocation "CR DC"
  syscontact info@sandfordit.com
  syscontact info@sandfordit.com
Line 177: Line 355:


=== Backup ===
=== Backup ===
http://www.cyberciti.biz/faq/ubuntu-linux-mysql-nas-ftp-backup-script/
Based on http://www.cyberciti.biz/faq/ubuntu-linux-mysql-nas-ftp-backup-script/
 
# Create the required folders using...
#* <code> mkdir backup </code>
#* <code> mkdir backup/mysql </code>
# Create the file below (editing as required) as <code> /backup/mysql.sh </code>
# Make the file executable
#* <code> chmod +x /backup/mysql.sh </code>
# Perform a test run of the backup
# Schedule the script to run with crontab
#* <code> crontab -e </code>
#* <code> 30 1 * * *      /bin/bash      /backup/mysql.sh </code>
 
<source lang="bash">
#!/bin/bash
 
### MySQL Server Login and local backup info ###
MUSER="root"
MPASS="password"
MHOST="localhost"
MYSQL="$(which mysql)"
MYSQLDUMP="$(which mysqldump)"
BAK="/backup/mysql"
LOG="/backup/mysql.log"
GZIP="$(which gzip)"
NOW=$(date -u +%Y%m%d)
 
## FTP info
FTPDIR="/Backup/db"
FTPUSER="backup"
FTPPASS="backup"
FTPSERVER="ftphost"
 
## Functions
Logger()
{
        echo `date "+%a %d/%m/%y %H:%M:%S"`: $1 >> $LOG
}
 
## Main Script
Logger "Started backup script..."
 
[ ! -d $BAK ] && mkdir -p $BAK
[ ! -d $BAK/tmp ] && mkdir -p $BAK/tmp
mv $BAK/* $BAK/tmp
 
DBS="$($MYSQL -u $MUSER -h $MHOST -p$MPASS -Bse 'show databases')"
for db in $DBS
do
FILE=$BAK/$db.$NOW.gz
Logger "Backing up $db to $FILE"
$MYSQLDUMP -u $MUSER -h $MHOST -p$MPASS $db | $GZIP -9 > $FILE
done
 
Logger "Completed local backup"
 
## FTP to remote server
ftp -in <<EOF
open $FTPSERVER
user $FTPUSER $FTPPASS
bin
cd $FTPDIR
lcd $BAK
mput *
close
bye
EOF
 
if [ "$?" == "0" ]; then
Logger "FTP upload completed successfully"
/bin/rm -f $BAK/tmp*
Logger "Previous local backup files removed"
else
Logger "FTP upload failed !!!"
fi
</source>
 


In some versions of MySQL you will receive an error similar to...
mysqldump: Got error: 1044: Access denied for user 'root'@'localhost' to database 'information_schema' when using LOCK TABLES
It appears to be a [http://bugs.mysql.com/bug.php?id=21527|MySQL bug], which seems to keep cropping up.  As a workaround change the <code> $MYSQLDUMP </code> line to 
<source lang="bash">
$MYSQLDUMP -u $MUSER -h $MHOST -p$MPASS --skip-lock-tables $db | $GZIP -9 > $FILE
</source>
Note that you won't backup the <code> information_schema </code> table if you need to implement this workaround


[[Category:VMware]]
[[Category:Zimbra]]
[[Category:MySQL]]
[[Category:MySQL]]
== Perl ==
=== Install Module ===
Installing a perl module isn't tricky, but there is a certain nack to it, see below...
# Get the module's package name (eg for Net::XWhois)
#* <code> sudo apt-cache search perl net::xwhois </code>
# Then install the package
#* <code> sudo apt-get install libnet-xwhois-perl </code>
=== Check Module(s) Installed ===
To check for a specific module use (checking for <code>Net::XWhois</code>)
perl -MNet::XWhois -e "print \"Module installed.\\n\";"
To list all installed modules
perl -MFile::Find=find -MFile::Spec::Functions -Tlwe \
'find { wanted => sub { print canonpath $_ if /\.pm\z/ }, no_chdir => 1 }, @INC'
Source: http://www.linuxquestions.org/questions/linux-general-1/how-to-list-all-installed-perl-modules-216603/
== Python ==
Python v2 comes pre-installed, however if you want to run newer Python 3 scripts, this will need to be installed alongside.
# Install the package
#* <code> apt-get install python3 </code>
#** Note that more than one version of Python 3 may be available, cancel the install are retry with specific version if required, eg <code> apt-get install python3.1 </code>
To enter the Python 3 interpreter, run <code> phython3 </code>, to make sure you get the right environment for a script use the following shebang
<source lang="python">
#! /usr/bin/env python3
</source>
See [[:Category:Python|Python]] for further info
[[Category:Python]]
== AWStats ==
=== Initial Setup ===
# Install the package
#* <code> apt-get install awstats </code>
# Edit the the generic template config file if required
#* <code> /etc/awstats/awstats.conf </code>
# Create apache config file for site with contents show below
#* eg <code> /etc/apache2/sites-enabled/awstats </code>
# Restart apache
#* <code> service apache2 restart </code>
# Site should now be available via URL similar to
#* http://yourserver/awstats/awstats.pl
<pre>
Alias /awstatsclasses "/usr/share/awstats/lib/"
Alias /awstats-icon/ "/usr/share/awstats/icon/"
Alias /awstatscss "/usr/share/doc/awstats/examples/css"
ScriptAlias /awstats/ /usr/lib/cgi-bin/
<Directory /usr/lib/cgi-bin/>
        Options ExecCGI -MultiViews +SymLinksIfOwnerMatch
        Order allow,deny
        Allow from all
</Directory>
<Directory /usr/share/awstats/>
        Order allow,deny
        Allow from all
</Directory>
</pre>
=== Add a Site ===
# Create a specific config file for the site to monitor
#* <code> cp /etc/awstats/awstats.conf /etc/awstats/awstats.mysite.com.conf </code>
# Edit the config file for the site, specifically (see below for further options)
#* <code> LogFile=”/path/to/your/domain/access.log” </code>
#* <code> LogFormat=1  </code>(this will give you more detailed stats)
#* <code> SiteDomain=”mysite.com” </code>
#* <code> HostAliases=”www.mysite.com localhost 127.0.0.1" </code> (example for a local site)
# Perform an initial stats gather for the site
#* <code> /usr/lib/cgi-bin/awstats.pl -config=mysite.com -update </code>
# Test that you can see some stats, using URL similar to
#* http://yourserver/awstats/awstats.pl?config=mysite.com
# Add a scheduled job to crontab to update automatically
#* <code> crontab -e </code>
#* EG every 30 mins <code> */30 * * * *    /bin/perl      /usr/lib/cgi-bin/awstats.pl -config=mysite.com -update >/dev/null </code>
Further options
* Wiki sites (and other sites where an URL parameter can specify a specific page
** <code> URLWithQuery=1 </code> - useful for Wiki's etc where query param indicates a different page
** <code> URLWithQueryWithOnlyFollowingParameters="title" </code> - only treats variances in param title as distinct pages
** <code> URLReferrerWithQuery=1 </code> follows on from two above
=== Other ===
To perform a one-off update from a specific log file...
* <code> /usr/lib/cgi-bin/awstats.pl -config=server -LogFile=access.log </code>
** Updates can only be added in chronological order, therefore you may need to delete the data file for a particular month, and rebuild it entirely.
Scheduled updates are configured in <code> /etc/cron.d/awstats </code>
== Syslog to MySQL Database ==
This procedure achieves three things...
# Allows remote hosts to use the local server as a syslog destination
# Directs syslogs to MySQL database on the server
# Allows viewing of syslogged events through [http://loganalyzer.adiscon.com/ LogAnalyser] web front end
...it is assumed that you already have a local MySQL and Apache server running!
# '''Set-up your server to send syslog messages to a MySQL database'''
#* <code> apt-get install rsyslog-mysql </code>
#* Enter the root password to your MySQL instance when prompted
# '''Update the <code> rsyslog </code> config (<code>/etc/rsyslog.conf</code>) to receive syslog data, and to route messages through a queue'''
## Uncoment the following..
##* <code>$ModLoad ommysql  # load the output driver (use ompgsql for PostgreSQL)</code>
##* <code>$ModLoad imudp    # network reception</code>
##* <code>$UDPServerRun 514 # start a udp server at port 514</code>
## Add the following...
##* <code>$WorkDirectory /rsyslog/work # default location for work (spool) files</code>
##* <code>$ActionQueueType LinkedList # use asynchronous processing</code>
##* <code>$ActionQueueFileName dbq    # set file name, also enables disk mode</code>
##* <code>$ActionResumeRetryCount -1  # infinite retries on insert failure</code>
## Restart the service
##* <code> service rsyslog restart </code>
# '''Install LogAnalyser'''
## Download latest build from http://loganalyzer.adiscon.com/downloads
##* EG <code>wget http://download.adiscon.com/loganalyzer/loganalyzer-3.5.0.tar.gz</code>
## Uncompress
##* EG <code>tar xf loganalyzer-3.5.0.tar.gz</code>
## Move the contents or <code>/src</code> to webserver
##* EG <code> mkdir /var/www/syslog </code>
##* EG <code> mv /src/* /var/www/syslog/ </code>
## Move utility scripts to same folder
##* EG <code> mv /contrib/* /var/www/syslog/ </code>
## Make them both executable,
##* EG <code> chmod +x /var/www/syslog/*.sh </code>
## Run the config script in the directory
##* EG <code> /var/www/syslog# ./configure.sh </code>
## Browse to webpage
##* EG http://your-www-svr/syslog/index.php
## Ignore the error, and follow the link to install (configure)
## Accept defaults until step 7, where you change the following
##* Name of the Source - ''your name for the local syslog db''
##* Source Type - MySQL Native
##* Database Name - Syslog
##* Database Tablename - SystemEvents
##* Database User - rsyslog
##* Database Password - rsyslog
## Config completed!
== Troubleshooting ==
=== Network ===
==== No NIC ====
Especially after hardware changes, its possible the networking config no longer refers to the right interface.
# Use <code> ifconfig </code> to confirm the current network config
# Use <code> dmesg | grep -i eth </code> to ascertain what's been detected at boot time
# Assuming it states that say <code>eth0</code> has been changed to <code>eth1</code> then just update the <code>/etc/network/interfaces</code> file
=== Software RAID ===
==== Replacing a RAID 1 Disk ====
This procedure was written from the following starting point...
* A machine originally with two disks in RAID1 has failed, one disk has been replaced, and machine started again
...and adapted from this post http://www.howtoforge.com/replacing_hard_disks_in_a_raid1_array
# Backup whatever you can before proceeding, one mistake or system error could destroy your machine
# Confirm which disk is new, and which is old (if the new disk is blank this is easy as there will be no partition info!)
#* <code> fdisk -l </code>
# Partition the new disk the same as the original
#* <code> sfdisk -d /dev/sda | sfdisk /dev/sdb </code>
# Confirm that the layout of both disks is now that same
#* <code> fdisk -l </code>
# Add the newly created partitions to the RAID disks
#* <code> mdadm --manage /dev/md0 --add /dev/sdb1 </code>
#* ''You may have more <code>sd</code> partitions than <code>md</code> partitions, the array size return through <code>mdadm -D /dev/md*</code> should roughly match the number of blocks found from <code>fdisk -l</code>''
# The arrays should now be being sync'ed, check progress by monitoring <code>/proc/mdstat</code>
#* <code> more /proc/mdstat </code>
=== SSH ===
==== Server Hostname Change ====
If the hostname (or IP) of the server you are SSH'ing to changes, the old entry needs to be removed from your SSH key known hosts file
* <code> ssh-keygen -R <name or IP> </code>
=== Reboot Required? ===
If a package update/installation requires a reboot to complete the following file will exist...
/var/run/reboot-required
To see which packages caused this to be set, inspect the contents of...
/var/run/reboot-required.pkgs
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