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Varnish log by Client IP address

by on Mar.15, 2013, under Uncategorized

varnishlog -c -m ‘ReqStart: xx.xxx.xx.xxx’

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No /etc/crontab on centos 6

by on Feb.14, 2013, under Uncategorized

CentOS 6.x has changed how the default system maintenance cronjobs are scheduled. These are the cron jobs responsible for things like rotating logs and indexing files on the filesystem. That is routine jobs that are best scheduled to run at off peak times when the server is not busy doing more important things like serving money making websites. So how do you go about changing the timing of cron jobs on CentOS or RHEL 6.x?

Or if you want more fine grained control you could just ditch anacron altogether and use /etc/cron.d/dailyjobs

yum remove cronie-anacron
yum install cronie-noanacron sysstat

service crond start
chkconfig crond on

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Svn Ignore Multiple Folders

by on Dec.04, 2012, under Uncategorized

If you need to ignore multiple folders in svn an easy way to do it is with:
svn propedit svn:ignore .

If you receive the below message:
None of the environment variables SVN_EDITOR, VISUAL or EDITOR are set

Try this:
vi ~/.bash_profile

and insert this line:

export SVN_EDITOR=vi

Note: This won’t work if the directory is already “in” svn. svn rm –keep-local dirname first.

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Dell Poweredge Server 2950 with PERC 5i Raid Controller Keeps Loosing Hard Drive in Array (Foreign Config)

by on Nov.19, 2012, under Uncategorized

So I had an odd issue with a dell poweredge 2950 server with 5 hard drives in it. They were Hitachi drives 2TB each. I would format the server and use software raid to create a raid 5. Upon turning off the server and booting back up one of the hard drives would be “removed” from the array.

I later realized a complete off shutdown -h now and a cold start were how to reproduce the issue.

I realized that hitachi had a firmware update for my hard drives since they had an issue in some 3ware controllers. My controller a perc 5i is a dell re-branded LSI controller – so I gave it a shot anyway. After flashing the drives I had the same result. I think you should flash the drives to bring them up to date if you are reading this.

What the actual cause of the issue was; I only plugged in one of the two redundant power supplies for the server. In the past, we ran this server with 2 hard drives and had no issue with it being fully functional running on one of the two PSU’s. So when we un-racked the server and brought it to the office for this rebuild we only plugged in one PSU. After all outlets are valuable! Well I plugged in the second PSU into the other wall jack/strip (a different one – I didn’t even bother trying the same jack/strip) and I have not seen the drive go into a “removed” state yet.

So far I have concluded this was the issue. My conclusion is the fact the issue was consistent before and no longer occurs. The reason behind this I think is that these 2GB drives draw alot of power from the server – the initial boot from a cold state requires that the drives spin up. All 5 drives, all fans, and all cpu’s are drawing much more power than regular at the same time during the boot from a cold start. This must have been draining the 750w power supply with my server and causing the PERC 5i to not see one of the drives or to mark it as removed since it did not gain a response in adequate time.

Well that was a waste of about 16-20 hours of work – no I can begin installing the actual software on this machine knowing my raid will be reliable.

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Installing php52 on centos 6

by on Nov.19, 2012, under Uncategorized

So, for some reason you need to install php 5.2 on centos6 (Ok Register Globals – because your client won’t pay for updating the software – right?)   So Here you go:     – Enable Atomicorp repo Run following command to enable Atomic YUM repo:

wget -q -O - http://www.atomicorp.com/installers/atomic | sh

– Disable PHP 5.3 Atomic repo contains both PHP 5.2 and 5.3. Official RHEL/CentOS 6 repo also contains PHP 5.3. To disable PHP 5.3, add following line to YUM configuration file /etc/yum.conf:

exclude=php-*5.3*

– Install PHP packages Use following commands to install PHP 5.2 packages:
arch=$(uname -m)

yum install yum install php.$arch php-bcmath.$arch php-cli.$arch php-common.$arch php-dba.$arch php-devel.$arch php-embedded.$arch php-fpm.$arch php-gd.$arch php-imap.$arch php-intl.$arch php-ioncube-loader.$arch php-ldap.$arch php-mbstring.$arch php-mcrypt.$arch php-mhash.$arch php-mysql.$arch php-ncurses.$arch php-odbc.$arch php-pdo.$arch php-pear.$arch php-pecl.$arch php-pgsql.$arch php-process.$arch php-rspell.$arch php-recode.$arch php-snmp.$arch php-soap.$arch php-tidy.$arch php-xml.$arch php-xmlrpc.$arch php-zts.$arch php-sqlite.$arch -y

Here, machine architecture (e.g. x86_64 for Intel 64-bit architecture) is stored in the variable arch and its value is appended to each PHP package to avoid installing same package from multiple architectures. The list of PHP packages to be installed may vary depending on your requirements. If you do not know the correct name for a PHP package, search for PHP packages with following command:

yum search php

This command will list RPM packages having the string ‘php’ in their name along with a short description for each package.

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List (LS) top biggest files or folders on linux file system

by on Sep.27, 2012, under Uncategorized

This command will list out the top biggest files or directories on the server.

resize; clear; date; echo "Largest Directories:"; du -hcx / | grep '^[0-9]*G'\
| sort -nr | head; echo ""; echo "Largest Files:"; nice -n 19 find / -mount \
-type f -ls|sort -rnk7 |head -10|awk '{printf "%d MB\t%s\n",($7/1024)/1024,$NF}'
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Using WGET to download a website including css/js/images

by on Sep.27, 2012, under Uncategorized

Example:

wget -e robots=off -p -k https://www.dws-investments.com/EN/products/dws-alternative-asset-allocation-fund.jsp?fund-key=4495

 

-e robots=off – wget ignores robots.txt which may tell spiders to not download files

-p  – get all assetts (css/images/js)

-k – convert links to relative not absolute

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