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Apache2 worker vs prefork for ISPConfig benchmark

I’ve been running ISPConfig latest version(3.0.4) on Amazon cloud t1.micro instance for some time to host several small sites, mostly WordPress. I’m quite happy with the performance of the instance. The OS is Ubuntu 10.04 LTS. Until recently I’ve used the default mpm which is prefork, but I decided to test out worker also. If you are wondering I use mod_fcgid for all the sites. That being said I performed several tests with ab (apache benchmark) to see which mpm can server most requests per second.

While I do not claim this is the best setup, I think worker is better suited for me. Some people said they had problems because of mpm worker. So far so good, but will update this post if there are any issues.

Test results:

prefork worker
Concurrency Level: 32
Time taken for tests: 7.834 seconds
Complete requests: 5000
Failed requests: 0
Write errors: 0
Keep-Alive requests: 4972
Total transferred: 84831033 bytes
HTML transferred: 83206915 bytes
Requests per second: 638.27 [#/sec] (mean)
Time per request: 50.136 [ms] (mean)
Time per request: 1.567 [ms] (mean, across all concurrent requests)
Transfer rate: 10575.21 [Kbytes/sec] received
Concurrency Level: 32
Time taken for tests: 7.096 seconds
Complete requests: 5000
Failed requests: 0
Write errors: 0
Keep-Alive requests: 4968
Total transferred: 84877824 bytes
HTML transferred: 83247322 bytes
Requests per second: 704.63 [#/sec] (mean)
Time per request: 45.414 [ms] (mean)
Time per request: 1.419 [ms] (mean, across all concurrent requests)
Transfer rate: 11681.17 [Kbytes/sec] received

Creating consistent backups for EBS with EXT4 and quota

What’s this about?
Data security and backups are very important aspects when you work with servers, especially if you are using cloud infrastructure. I am using AWS(Amazon Web Services) as my preferred IaaS, so the following how-to is tailored for Amazon EC2 instances using EBS as storage for the web sites files. On my instance I have Ubuntu 10.04 LTS installed and on top of it I run ISPConfig 3.0.4(latest version at the moment I write this article). Some of the programs required to run this setup were already installed, but it should be pretty obvious if you miss anything. If you need help you can either leave a comment or contact me via email.

The following setup will allow you to create an EBS using EXT4 as file system, with quota enabled on it(for ISPConfig) and weekly backups of the EBS. In case of instance failure you should be able to launch a new instance and attach the EBS, without losing any web sites files. In case of EBS failure you can recreate one from the most recent snapshot.

Create an EBS in the same zone as your instance and attach it to your instance as /dev/sdf. This can be easily done from AWS Management Console.

Install xfsprogs
sudo apt-get install xfsprogs

Create EXT4 filesystem on /dev/sdf
sudo mkfs.ext4 /dev/sdf

Now mount it temporarily
sudo mkdir /mnt/ebs
sudo mount /dev/sdf /mnt/ebs

Stop the apache2 web server and copy the files to /mnt/ebs
sudo service apache2 stop
cd /mnt/ebs
sudo cp -rp /var/www/* .

Prepare quota
touch quota.user quota.group
sudo chmod 600 quota.*

Add the entry to /etc/fstab
/dev/sdf /var/www ext4 noatime,nobootwait,usrjquota=quota.user,grpjquota=quota.group,jqfmt=vfsv0 0 0

Unmount the EBS and remount it to /var/www
sudo umount /dev/sdf
sudo mount /dev/sdf /var/www -o noatime,usrjquota=quota.user,grpjquota=quota.group,jqfmt=vfsv0

Enable quota
sudo quotacheck -avugm
sudo quotaon -avug

Start the apache2 web server and check that the web sites are working properly
sudo service apache2 start

Install ec2-consistent-snapshot script for weekly backups of EBS
sudo add-apt-repository ppa:alestic
sudo apt-get update
sudo apt-get install -y ec2-consistent-snapshot

Prepare first snapshot(I assume the cron will run as root user, hence I create the awssecret file in /root directory)
sudo touch /root/.awssecret
sudo chmod 600 /root/.awssecret

Edit .awssecret and add following lines, in this order, replacing ACCESS_KEY_ID and SECRET_ACCESS_KEY with your own, both can be found under Account->Security Credentials:
ACCESS_KEY_ID
SECRET_ACCESS_KEY

Test the snapshot creation with debug mode activated, replace VOLUME_ID with the right volume ID:
sudo ec2-consistent-snapshot --debug --description "snapshot $(date +\%Y-\%m-\%d-\%H:\%M:\%S)" --freeze-filesystem /var/www vol-VOLUME_ID

If everything went well you should be able to see your new snapshot in the AWS Management Console.

Finally add this to your root crontab (by running sudo crontab -e):
@weekly /usr/bin/ec2-consistent-snapshot --debug --description "snapshot $(date +'%Y-%m-%d %H:%M:%S')" --freeze-filesystem /var/www vol-VOLUME_ID>>/var/log/backup.log 2>&1
Make sure you put the correct VOLUME_ID!

This should be all, you now have all your web sites on EBS, quota is enabled and weekly backups enabled. I think I pretty much nailed everything you need in order to perform this setup, but if there are any issues feel free to leave a comment. Also I love getting feedback so if you found this article useful leave a comment also :)

ISPConfig3 running on Ubuntu 9.10 on AWS

This is an idea on how to set ISPConfig 3 on Amazon EC2 for web hosting. It’s still work in progress and I await for any constructive feedback. Since English is not my first language there might be some grammatical errors.

Prerequisites:

  • AWS Account
  • Some Linux experience

Part I – Setting up AWS

I have done all the setup of instance and ebs from the Amazon Management Console. It has a very intuitive interface and it’s so easy to work with.

Optional: You can purchase reservation for an instance if you are planing to run it 24/7. To do so go to Instances -> Reserved Instances and click on Purchase Reserved Instance. For example a c1.medium instance reservation for 1 year costs 455$ one time fee and the hourly cost of the instance goes to 0.06$/hour. It’s your decision, do the math if it’s worth it or not to go with reserved instances.

  1. From the Management Console go to Volumes and Create Volume. I created a 40 GB volume in us-east-1a zone, choose an appropriate value for your needs.
  2. Next step which is also optional is to get an Elastic IP for your instance. Go to Elastic IPs and click Allocate New Address.
  3. You will need a keypair to access your instance. You can create one before launching the instance or create one when you also setup the new instance. Your choice. I created one before by going to Key Pairs -> Create Key Pair.

Part II – Launching the instance

Instance type used was c1.medium, the AMI for it was Ubuntu 9.10 Karmic 32bit ami-1515f67c from Canonical Images for Amazon EC2.

Go to Instances and press Launch Instance and make sure you set it to use ami-1515f67c. If you need to use a different zone or a 64 bit instance you can check the alestic page which is a wonderful resource for Ubuntu images for EC2. I would also suggest to join their EC2 Ubuntu Google Grup if you are serious about AWS + Ubuntu.

After the instance is up and running attach the Elastic IP and the Volume you have created to it. To attach the IP go to Elastic IPs and select Associate, for the EBS go to Volumes. I attached the EBS as /dev/sdb to the instance.

Later Edit: You will need to also modify the Security Groups and permit access on ports 22(SSH), 80(HTTP), 8080(ISPConfig 3), 20-21(FTP) -> still need more work to support PASV.

Part III – Install ISPConfig 3

Before proceeding with ISPConfig 3 setup connect to your instance and update the packages.

sudo su
apt-get update
apt-get upgrade

Note: You will have to connect to your instance using the ubuntu username and the key pair you generated for that instance. It won’t allow you to connect directly as root.

To install the ISPConfig 3 I followed the HowtoForge excellent tutorial with a small exception: I skipped the part of setting up the quota since I was planning to use the EBS as storage for sites and MySQL databases. The rest of the tutorial was just perfect.

Part IV – Setting up the EBS and ISPConfig to work with it

Most of the stuff and talk about EBS and MySQL snapshots is discussed on Amazon developer forums in the thread called Tutorial: Running MySQL on Amazon EC2 with EBS (Elastic Block Store). Make sure you read the discussion before or after you are done with this post.
apt-get install dmsetup
modprobe dm_mod
modprobe dm_mirror
modprobe dm_snapshot
mkdir /dev/.static/dev/mapper -pv

Create ext3 filesystem:

mkfs.ext3 /dev/sdb

Setup it with dmsetup

echo 0 `blockdev --getsize /dev/sdb` linear /dev/sdb 0 | dmsetup create ebs

Add the records to fstab

echo "/dev/mapper/ebs /ebs ext3 noatime,usrjquota=aquota.user,grpjquota=aquota.group,jqfmt=vfsv0 0 0" >> /etc/fstab

Setup quota

touch /ebs/aquota.user /ebs/aquota.group
chmod 600 /ebs/aquota.*
mount -o remount /ebs

Enable quota on ebs

quotacheck -avugm -F vfsv0 /ebs
quotaon -avug /ebs

For websites:

mkdir /ebs/sites
ln -s /ebs/sites /var/www/clients

Jailkit:

Set Jailkit chroot home: /ebs/home/[username]

mkdir /ebs/home

MySQL:

/etc/init.d/mysql stop
mkdir /ebs/mysql/data /ebs/mysql/log -pv
mv /var/lib/mysql /ebs/mysql/data
ln -s /ebs/mysql/data/mysql /var/lib/mysql
mv /var/log/mysql /ebs/mysql/log
ln -s /ebs/mysql/log/mysql /var/log/mysql

To make a snapshot of the database, go to the mysql console (msqyl -p)

FLUSH TABLES WITH READ LOCK;
SHOW MASTER STATUS;
SYSTEM dmsetup suspend /dev/mapper/ebs

Take your snapshot of the EBS

SYSTEM dmsetup resume /dev/mapper/ebs
UNLOCK TABLES;

Note:This is still work in progress, any advices on how to improve it are greatly appreciated and any constructive criticism also.

ISPConfig3: Updating to myDNS-ng

If you have followed the tutorials “the perfect setup” for installing ISPConfig 3 chances are that you have an older myDNS version (1.1.0 or so). Since I had a few problems with that version I decided to update to myDNS-ng, the latest version.

In this article I will refer to rpmbuilder user, a user I create to compile and/or make RPMs. For more information on how to set it up check this link.

Also the instructions are for CentOs 5.4(but will probably work for any other 5.x version).

su - rpmbuilder
cd /tmp
wget http://downloads.sourceforge.net/project/mydns-ng/mydns/1.2.8.27/mydns-1.2.8.27.tar.gz?use_mirror=garr
tar zxvf mydns-1.2.8.27.tar.gz
cd mydns-1.2.8
./configure
make

Everything should be ok untill now. I had no problems to compile it. Then I decided to use checkinstall.
sudo yum install checkinstall
checkinstall

It will ask you a few questions, answer them and you should have a rpm package in /usr/src/redhat/RPMS. It will tell you anyway where he created the rpm.
After that I removed the old mydns packages and installed the new one as root:
service mydns stop
yum remove mydns mydns-mysql
yum install /usr/src/redhat/RPMS/i386/mydns-1.2.8-1.i386.rpm --nogpgcheck

After that I needed to create mydns start script:
vi /etc/init.d/mydns
chmod +x /etc/init.d/mydns

I used the script posted by rukus77 on howtoforge. Make sure you read all the comments on that forum (especially the one containing [ -f /usr/sbin/mydns ] || exit 1).
The last step is to run ISPConfig 3 setup:
cd ispconfig3_install/
cd install
php -q update.php

When asked if to reconfigure services answer yes, the rest you can answer no.

That would be all, thanks for reading.