Rackspace – Cloud Sever autokill script 

#!/bin/bash

# This script auto delete the current instance and ask the
# Autoscale Group to replace the node


###########################################################

CRED_FILE=/opt/autoscale/.credentials
AS_GRP_ID=a17b08b3-0c04-48e8-84a9-3070c29a27fa

###########################################################

# Gather info from credential file
USERNAME=$(grep username $CRED_FILE | awk -F= '{print $2}' | sed 's/ //g')
APIKEY=$(grep api_key $CRED_FILE | awk -F= '{print $2}' | sed 's/ //g')
REGION=$(grep region $CRED_FILE | awk -F= '{print $2}' | sed 's/ //g' | tr '[:upper:]' '[:lower:]')


SERVER_UID=$(xenstore-read name | sed 's/instance-//')

AUTH=$(
curl -sd \
"{
   \"auth\":
   {
        \"RAX-KSKEY:apiKeyCredentials\":
        {\"username\": \"$USERNAME\",
        \"apiKey\": \"$APIKEY\"}        }
}" \
-H 'Content-Type: application/json' \
'https://identity.api.rackspacecloud.com/v2.0/tokens' | python -m json.tool | grep -A 7 token | awk '/id/ { print $2 }' | tr -d '"' | tr -d ","
) 

TOKEN=$(echo $AUTH | awk '{print $1}')
ID=$(echo $AUTH | awk '{print $2}')


curl -sH "X-Auth-Token: $TOKEN" -H "Content-type: application/json" -X DELETE https://$REGION.autoscale.api.rackspacecloud.com/v1.0/$ID/groups/$AS_GRP_ID/servers/$SERVER_UID?replace=true

Scheduled unattended tasks – at 

$ at time date

$ at 11 am may 20

# at 02:00 AM Fri
at> yum update glibc
at> echo "Executing scheduled task" | logger
at> shutdown -r +5 "Server is going to be rebooted in 5 minutes for scheduled task. Please save your work ASAP." 
at> <EOT>
job 2 at 2015-02-06 02:00

Ends using CTRL+D that generates the <EOT> bit.

Source: http://www.computerhope.com/unix/uat.htm

Check the processes in the queue

atq

Check content of a job

at -c <job number>

Delete job

atrm <job number>

Also, you can cat/modify the job in /var/spool/cron/atjobs/ or /var/spool/at (in Centos)

If not installed, on Centos, make sure to start also ‘atd‘ service.

# chkconfig atd on && service atd start

WordPress Apache ProxyPass

Option 1

Ensure certain traffic goes to a certain server, you can use this:

<LocationMatch "^/wordpress/wp-admin/?.*>
        ProxyPreserveHost On
        ProxyPass http://ip.of.master.server/
</LocationMatch>

Option 2

Step One: Configure Environment

We need to setup some environment variables to get this to work correctly.
Add the following to your environment on the slave server(s):

RHEL/CentOS: /etc/sysconfig/httpd

OPTIONS="-DSLAVE"
export MASTER_SERVER="SERVERIP HERE"

Ubuntu: /etc/apache2/envvars 

OPTIONS="-DSLAVE"
export MASTER_SERVER="SERVERIP HERE"

Step Two: Configure your VirtualHost

In your VirtualHost configuration do something like the following.

RewriteEngine On
ProxyPreserveHost On
ProxyPass /wp-admin/ http://${MASTER_SERVER}/wp-admin/
ProxyPassReverse /wp-admin/ http://${MASTER_SERVER}/wp-admin/

RewriteCond %{REQUEST_METHOD} =POST
RewriteRule . http://${MASTER_SERVER}%{REQUEST_URI} [P]

Fullstatus Apache 2.4 Centos7

Apache on CentOS 7 doesn’t come with any configuration for enabling /server-status
The module does come by default though, so to get this going, all you need to do is:

$ cat >> /etc/httpd/conf.modules.d/01-status.conf << EOF
<Location /server-status>
SetHandler server-status
Require local
</Location>
EOF

$ systemctl reload httpd
$ apachectl fullstatus

APC (php module) and OPcache 

apt-get install php-apc

apc
apc.shm_size=256M

cp /etc/php.d/apc.ini /home/rack && sed -i 's/^.*apc.shm_size=.*$/apc.shm_size=256M/' /etc/php.d/apc.ini && grep "apc.shm_size=" /etc/php.d/apc.ini

cp  /usr/share/doc/php*apc*/apc.php /var/www/

service httpd graceful && service httpd status

PHP5.5 -> If it has Zend OPcache it doesn’t need APC anymore

php -m

Look for this:

[Zend Modules]
Zend OPcache

GUI: https://github.com/amnuts/opcache-gui

wget https://raw.githubusercontent.com/amnuts/opcache-gui/master/index.php

/etc/php5/mods-available/opcache.ini or /etc/php5/fpm/conf.d/05-opcache.ini

opcache.memory_consumption=128
opcache.interned_strings_buffer=8
opcache.max_accelerated_files=4000
opcache.revalidate_freq=60
opcache.fast_shutdown=1
opcache.enable_cli=1

One liners alternative for apachebuddy


average apache process mem usage

ps -H h -ylC httpd | perl -lane '$s+=$F[7];$i++;END{printf"Avg=%.1fMB\n",$s/$i/1024}' 
ps -H h -ylC apache2 | perl -lane '$s+=$F[7];$i++;END{printf"Avg=%.1fMB\n",$s/$i/1024}'

highest process mem usage cd

ps -H h -ylC httpd | awk 'function max(x){i=0;for(val in x){if(i<=x[val]){i=x[val];}}return i;}function min(x){i=max(x);for(val in x){if(i>x[val]){i=x[val];}}return i;}/^#/{next}{a[$8]=$8;next}END{minimum=min(a);maximum=max(a);print "Max = "maximum / 1024 "MB";print "Min = "minimum / 1024"MB"}' 
ps -H h -ylC apache2 | awk 'function max(x){i=0;for(val in x){if(i<=x[val]){i=x[val];}}return i;}function min(x){i=max(x);for(val in x){if(i>x[val]){i=x[val];}}return i;}/^#/{next}{a[$8]=$8;next}END{minimum=min(a);maximum=max(a);print "Max = "maximum / 1024 "MB";print "Min = "minimum / 1024"MB"}'

php-fpm – www pool average

for pid in $(ps aux | grep fpm | grep "pool www" | awk '{print $2}'); do pmap -d $pid | tail -1 ; done | sed 's/K//' | awk '{sum+=$4} END {print sum/NR/1024}'

php-fpm – ALL active pools average memory

Ubuntu: cd /etc/php5/fpm/pool.d
Centos: cd /etc/php-fpm.d/
for pool in `ls *.conf` ; do POOL="`echo $pool | sed 's/\.conf//'`" ; echo -e "\n$POOL" ; for pid in $(ps aux | grep fpm | grep "pool $POOL" | awk '{print $2}'); do pmap -d $pid | tail -1 ; done | sed 's/K//' | awk '{sum+=$4} END {print sum/NR/1024}' ;  done

MANUAL CHECKS (understanding)

# ps aux | grep apache2 (or httpd)

USER       PID %CPU PerformanceOptimized %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND

-> RSS is the real memory value
-> VSZ is the one that it might reach (important mostly for MySQL)

# Quicker way is to do top and than press ‘>’

phpMyAdmin – from “source”

Get latest version

wget https://files.phpmyadmin.net/phpMyAdmin/4.4.14/phpMyAdmin-4.4.14-all-languages.zip

Unzip in /var/www/pma

Create config file

cp config.sample.inc.php config.inc.php

Create phpmyadmin db

mysql < create_tables.sql

Create user 

mysql -e "GRANT SELECT, INSERT, DELETE, UPDATE ON phpmyadmin.* TO 'pmaadmin'@'%' IDENTIFIED BY '<PASS>'"

Enable parts related to the db, username and pw from above

vim config.inc.php

Create configuration file (copy and paste the whole command):

cat > /etc/httpd/conf.d/phpMyAdmin.conf <<EOF
Alias /phpMyAdmin /var/www/html/pma
Alias /phpmyadmin /var/www/html/pma

<Directory /var/www/html/pma/>
     AuthType Basic
     AuthName "Restricted"
     AuthUserFile /etc/phpMyAdmin/.htpasswd
     Require valid-user
</Directory>
EOF

Create auth file

htpasswd -c  /etc/phpMyAdmin/.htpasswd admin
(FYI 'admin' it's the username)

To ADD users, just remove the -c flag