General
This page will be used for articles and non-specific information.
apt-get upgrade option
Automatically restart services
Written by Leon Teale
cd /root vim filename.sh #(e.g apachemonitor.sh)
Put the below script in it for Apache2. Replace the service in the ="apache2" field for other processes such as mysql etc.
#!/bin/bash
limit=0
admin=youremailaddress@gmail.com
service="apache2" #or replace this with httpd
process=`ps aux | grep "$service" | grep -v grep | wc -l`
if
[ "$process" -le "$limit" ] ;
then
if
[ ! -f /root/apachedown ];
then
echo "$service is not running" | mail -s "$service" $admin
/etc/init.d/apache2 restart #replace this with httpd
touch /root/apachedown
else
/etc/init.d/apache2 restart #replace this with httpd
fi
else
echo "$service is running"
if
[ -f /root/apachedown ];
then
rm /root/apachedown
else
echo ""
fi
fi
Then run:
chmod +x /root/filename.sh crontab -e
Add into crontab -e the following:
* * * * * sh /root/filename.sh
Character Map
Put a semi colon ; after the code below to display the arrows.
&larr = Left Arrow ←
&rarr = Right Arrow →
&uarr = Up Arrow ↑
&darr = Down Arrow ↓
&harr = Left and Right Arrow ↔
&crarr = Corner Arrow ↵
Check MySQL database size
SSH into your server, enter MySQL. If it uses WHM/cPanel log into WHM and go to the SQL Services menu > MySQL Root Password and set it there.
For a Plesk server:
mysql -uadmin -p`cat /etc/psa/.psa.shadow`;
For other servers.
mysql -p
Then:
show databases; use database show table status;
Look at the Data_length column for each table, which is in bytes.
Clear your browser cache
http://support.mozilla.org/en-US/kb/clear-cache-delete-temporary-files-fix-issues
http://support.google.com/chrome/bin/answer.py?hl=en&answer=95582
http://webdesign.about.com/cs/internetexplorer/ht/htclearcacheie.htm
http://www.refreshyourcache.com/en/safari
Cloud Hosting
Cloud is good for redundancy particularly if your site is heavily hit and is quite dynamic as multiple copies of your data is spread across several servers.
Create an any size test file
For Virtual Private Servers:
dd if=/dev/zero of=/testfile bs=15M count=1
This also tests the write speed of the disk.
For Dedicated Servers:
dd if=/dev/zero of=/dev/null bs=1M count=32768
Current Windows OS on Webfusion VPS
- Windows Web for Standard and Community packages
- Windows Standard for Business and Developer packages
- Windows Enterprise for Enterprise package
Empty a file
:> /file/path
This always exits true, but produces no output. Good for large old log files.
File exceeds maximum allowed size in joomla
If you see the following image, check one of the below threads:
http://forum.joomla.org/viewtopic.php?f=431&t=660927&view=next
http://www.cmsmind.com/joomla-1-7-help-how-to-modify-the-max-image-upload-size
http://www.simplemachines.org/community/index.php?topic=246794.0
Google Products
AdWords
Google AdWords lets you create an advert for your website and decide which Google search terms you would like to trigger your advert. When people search on Google using these terms, your advert is displayed. You pay a little out of a voucher only when someone clicks on the advert and visits your website.
Google Adsense is the opposite of this effectively.
Analytic's on Media Wiki
cd /var/www/vhosts/domain.com/mediawiki-install-folder/extensions wget https://sites.google.com/site/rutisextensions/googleAnalytics.zip unzip googleAnalytics.zip cd googleAnalystics chown ftpuser:psacln googleAnalytics.i18n.php googleAnalytics.php
vim googleAnalytics.php
Edit Line 19:
$wgGoogleAnalyticsAccount = "enter-GA-code-here";
Edit Line 25:
function efGoogleAnalyticsHookText($skin, &$text = '')
Exit the file.
cd /var/www/vhosts/domain.co.uk/httpdocs vim LocalSettings.php
Add in the following at the bottom of the file:
require_once( "$IP/extensions/googleAnalytics/googleAnalytics.php" );
Then you may need to create this file.
vim analyticstracking.php
Add in the following script:
<script type="text/javascript">
var _gaq = _gaq || [];
_gaq.push(['_setAccount', 'enter-GA-code-here']);
_gaq.push(['_trackPageview']);
(function() {
var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;
ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);
})();
</script>
To migrate your website to another server, you just keep the same files as Google will pick up the site from the new server (and therefore the Google Analytics information above).
PageSpeed
https://developers.google.com/speed/docs/mod_pagespeed/download
Ubuntu/Debian:
wget https://dl-ssl.google.com/dl/linux/direct/mod-pagespeed-stable_current_amd64.deb dpkg -i mod-pagespeed-stable_current_amd64.deb service apache2 restart
ModPagespeedEnableFilters
vim /etc/apache2/mods-enabled/pagespeed.conf
ModPagespeedEnableFilters defer_javascript ModPagespeedEnableFilters rewrite_css ModPagespeedEnableFilters fallback_rewrite_css_urls ModPagespeedEnableFilters rewrite_javascript
service apache2 restart
Image Scaler
Install OpenManage
CentOS 5.5 and 6:
wget -q -O - http://linux.dell.com/repo/hardware/latest/bootstrap.cgi | bash yum install srvadmin-all
If the below ones fail, looking up a solution currently (29/04/13)
Ubuntu 6:
echo 'deb http://linux.dell.com/repo/community/deb/latest /' | sudo tee -a /etc/apt/sources.list.d/linux.dell.com.sources.list gpg --keyserver pool.sks-keyservers.net --recv-key 1285491434D8786F gpg -a --export 1285491434D8786F | apt-key add - apt-get update apt-get install srvadmin-all
Ubuntu 8:
echo 'deb http://linux.dell.com/repo/community/deb/latest /' | sudo tee -a /etc/apt/sources.list.d/linux.dell.com.sources.list gpg --keyserver pool.sks-keyservers.net --recv-key 1285491434D8786F gpg -a --export 1285491434D8786F | apt-key add - apt-get update apt-get install srvadmin-all
Invalid Certificate
If you receive this error in Chrome on https:
"... but the server presented an invalid certificate."
Go to Tools > Options > Under the Hood > untick HTTPS/SSL - Check for server certificate revocation
^M
If lines in a file end in ^M this normally means the file has been edited using a DOS editor. You can remove these manually or using the dos2unix utility.
Ensure /etc/passwd doesn't have dos line endings:
file /etc/passwd
/etc/passwd: ASCII text, with CRLF, LF line terminators
To fix:
dos2unix /etc/passwd file /etc/passwd
/etc/passwd: ASCII text
Notification stuck on Android
No matter what type of browser you were using, you need to go into Settings > Phone > Apps > All > Download Manager and do Clear Data as well as untick and tick Show Notifications.
Operating Systems PHP, Apache, MySQL, Perl and Python Versions
| Operating System | PHP | Apache | MySQL | Perl | Python |
| Fedora Core 2 | 4.3.10 | 2.0.51 | 4.1.21 | Unknown | Unknown |
| Ubuntu 6.06 LTS | 4.4.2 - 5.1.3 | 2.0.55 | 5.0.22 | 5.8.7 | 2.4.2 |
| Ubuntu 8.04 LTS | 5.2.4-5.2.9 | 2.2.8 | 5.0.51 - 5.0.96 | 5.8.8 | 2.5.2 |
| Ubuntu 10.04 LTS | 5.3.2 | 2.2.14 | 5.1.41-5.5 | 5.10.1 | 2.6.5 |
| Ubuntu 12.04 LTS | WIP | 2.2.22+ | WIP | WIP | WIP |
| CentOS 5.5/5.7 | 5.1.6-5.3.3-5.3.6 | 2.2.3 | 5.0.77 | 5.3.10 | 2.4.3 |
| CentOS 6.2 | 5.3.3-5.4 | 2.2.15 - 2.2.22 | 5.1.52 | 5.8.8 | 2.6.6 |
| Windows Web VPS | 5.2.17 - 5.3.5 | SQL 2008 R2 Express (free) |
Check here to see how to check the SQL version/edition on Windows.
For CentOS PHP 5.3.3 check if you are using a 64 bit system (most likely). If so you need to use x86_64.
Outlook
http://www.msoutlook.info/question/250 Do not automatically mark as read]
Recall a message in Outlook 2010
Go to your Sent Items folder, double click the message. Make sure in the top right the chevron is a ^ not a v so you can see the Toolbar/Ribbon, then click Actions, then Recall This Message.
Web App signature is greyed out
This happens in Google Chrome. Use Firefox or Internet Explorer to set it in Options > See All Options > Settings > Mail tab > E-mail Signature
PS3 Media Server
Video skipping
There are many reasons for this. See the following threads:
http://tehparadox.com/forum/f28/ps3-media-server-watch-your-1080p-mkv-movies-easy-518971/
http://www.ps3mediaserver.org/forum/viewtopic.php?f=6&t=3507&start=30#p38969
A fix that worked for me was to go into C:\Program Files (x86)\PS3 Media Server\PMB.bat and edit:
start javaw -Xmx768M #to be the following start javaw -Xmx3072M
This allocates ~3GB of RAM to Java instead of 768MB. I would advise making a copy of the file first, make a copy of the file elsewhere and edit the value in that second copy, remove the original file and then place the second copy into the folder. This is because it will likely say the file is in use even if you stop PMS, Java, your browser and other services.
Audio out of sync
Method 1) Go into Transcoding Settings > Video/Audio decoder settings > Untick A/V sync alternative method
Method 2) Go into Transcoding Settings > Video/Audio decoder settings > Tick or untick Force framerate parsed from FFmpeg
Method 3) Option 11
Also, using .crt subtitles can cause the same issue. See: http://www.ps3mediaserver.org/forum/viewtopic.php?f=6&t=13366
Random Technical Terms
More to be added.
HAC = High Availability Clustering
SAN = Storage Area Network
NAS = Network-Attached Storage
CSV = Comma-Separated Values
DK - Java Development Kit
JRE - Java Runtime Environment
Java SE - Java Standard Edition
SE defines a set of capabilities and functionalities; there are more complex editions (Enterprise Edition - EE) and simpler ones (Mobile Edition - ME - for mobile environments).
The JDK includes the compiler and other tools needed to develop Java applications; JRE does not. So, to run a Java application someone else provides, you need JRE; to develop a Java application, you need JDK.
More information at Sun's Java web site, and in particular from the Java SE section, (2nd option, Java SE Development Kit (JDK) 6 Update 10).
Slightly increase performance on *nix server
This is not guaranteed!
apt-get update apt-get install prelink preload
If you do not use mod_perl or mod_python on your websites, disabling these may decrease memory usage.
Chrome
Add as a search engine
Right click the search box and click the option above. Then in the Name or Keyword box enter the prefix you want to type to initiate the search function.
Firefox
Bookmarks location
C:\Users\user\AppData\Roaming\Mozilla\Firefox\Profiles\0aaaa0a0.default\bookmarkbackups
Add a Keyword for This Search
In Firefox you can skip a page and use a keyword to search directly from the URL bar. To set this up first right-click on the search box and choose 'Add a Keyword for This Search'. That prompts to create a bookmark; give it a name and a short keyword (such as "skb" for this site). You will then be able to search just by going to the URL bar and entering skb *space* and then for example: Plesk
VNC
You can use VNC often to diagnose issues whereby you have issues logging into your server. VNC does not rely on virtual machine network connectivity as it's the equivalent of plugging a monitor/keyboard/mouse into a physical machine.
To VNC to a console higher then 100, simply use :60** where ** is the last 2 digits of the console number.
Several good VNC programs are mRemote, Tight VNC or RealVNC.
www to non-www
Guides for Magento: 1, 2 and 3
See second response in here as to why a Magento installation may show the IP instead of the domain name when going to your website.
