#ubuntu

Linux

Vagrant – Failed to mount folders in Linux guest

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I usually use Vagrant in Development Environment.  I need Vagrant to create Ubuntu Server on Windows 10 Desktop. Everthing work fine until one day, I met an error “Failed to mount folders in Linux guest”.

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==> nodeone: Setting hostname...
==> nodeone: Configuring and enabling network interfaces...
==> nodeone: Mounting shared folders...
    nodeone: /vagrant => E:/Vagrant/bean-seed
Failed to mount folders in Linux guest. This is usually because
the "vboxsf" file system is not available. Please verify that
the guest additions are properly installed in the guest and
can work properly. The command attempted was:
 
mount -t vboxsf -o uid=`id -u vagrant`,gid=`getent group vagrant | cut -d: -f3` vagrant /vagrant
mount -t vboxsf -o uid=`id -u vagrant`,gid=`id -g vagrant` vagrant /vagrant
 
The error output from the last command was:
 
stdin: is not a tty
/sbin/mount.vboxsf: mounting failed with the error: No such device

So I fixed it by command below:

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vagrant plugin install vagrant-vbguest

Education is the most powerful weapon which you can use to change the world

Education is the most powerful weapon which you can use to change the world

If you meet an error as below

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$ vagrant plugin install vagrant-vbguest
The directory where plugins are installed (the Vagrant home directory)
has a space in it. On Windows, there is a bug in Ruby when compiling
plugins into directories with spaces. Please move your Vagrant home
directory to a path without spaces and try again.

You have to change Vagrant Home Directory to a path without spaces.

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# just an example
export VAGRANT_HOME="/e/Vagrant/"

 

Nguyen Sy Thanh Son

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Docker, Linux

Install Docker in Ubuntu 14.04

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Docker is a platform of developer and sysadmins .  With Docker, you will be able to push whole your virtual machines  to cloud.  So you could easily use it everywhere and every time, or share to other people. I will share you the details of Docker installation in Ubuntu 14.04

Install Docker via apt-get:

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sudo apt-get update
sudo apt-get install docker.io

Run bash completion:

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source /etc/bash_completion.d/docker.io

Install Apt Transport Https:

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sudo apt-get update && apt-get install apt-transport-https

Then, add the Docker repository key to your local keychain.

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sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 36A1D7869245C8950F966E92D8576A8BA88D21E9

Open /etc/apt/sources.list.d/docker.list and add text:

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deb https://get.docker.com/ubuntu docker main

And now, install lxc-docker package:

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sudo apt-get update
sudo apt-get install lxc-docker

Test:

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sudo docker run -i -t ubuntu /bin/bash

 

 

Nguyen Sy Thanh Son

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Linux

Add user to group Ubuntu

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This article to show you some commands that are usually used to moderate user and group in Ubuntu.

Create new user with home directory:

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useradd -m -p `mkpasswd [password]` -s /bin/bash [username]

Remove user with related files:

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userdel -r [username]

Show groups of user:

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sudo groups [user_name]

Or

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id -gG www-data

And supplementary group to user:

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sudo usermod -a -G [group_name] [user_name]

Change user default groups:

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sudo usermod -g [group_name] [user_name]

 

Nguyen Sy Thanh Son

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Linux

htaccess htpasswd Ubuntu

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In this example, I assume that you want to all user have to input username/password when access http://localhost/test. And web root directory is /var/www/test.

Make sure that your web server was enable mod_rewrite. And your virtual host allow override all:

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AllowOverride All
Allow from All

To use htpasswd command , you need install apache2-utils:

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sudo apt-get install apache2-utils

To implement it, firstly, you create .htpassword file by command:

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htpasswd -c /var/www/test/.htpasswd [user_name]

And then, create .htaccess file:

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vi /var/www/test/.htaccess

With content:

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AuthUserFile /var/www/test/.htpasswd
AuthName "Authorization Required"
AuthType Basic
Require valid-user

Please make note that you have to use absolute path for .htpasswd file.

Done, try a test: http://localhost/test

Nguyen Sy Thanh Son

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Linux

Add new hard disk in ubuntu

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You are using linux on virtual machine (e.g VMWARE) or real PC. I will show you the way how to add new hard disk in ubuntu

Check new device:

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thanhson1085@sonnst:~$ ls /dev/sd*
/dev/sda  /dev/sda1  /dev/sda2  /dev/sda5  /dev/sdb

/dev/sdb is new hard disk that you needed. In case, you do not see new devive, it means that the OS system does know about new device. So you should reboot your system, If still not, you need install driver software for new device (read device specification and download drivers from device provider)

Be so busy improving yourself that you have no time to criticize others

Be so busy improving yourself that you have no time to criticize others

Start with command:

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fdisk /dev/sdb

Follow the guide to add a new partition

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Device contains neither a valid DOS partition table, nor Sun, SGI or OSF disklabel
Building a new DOS disklabel with disk identifier 0x2a749bbb.
Changes will remain in memory only, until you decide to write them.
After that, of course, the previous content won't be recoverable.
 
Warning: invalid flag 0x0000 of partition table 4 will be corrected by w(rite)
 
Command (m for help): m
Command action
   a   toggle a bootable flag
   b   edit bsd disklabel
   c   toggle the dos compatibility flag
   d   delete a partition
   l   list known partition types
   m   print this menu
   n   add a new partition
   o   create a new empty DOS partition table
   p   print the partition table
   q   quit without saving changes
   s   create a new empty Sun disklabel
   t   change a partition's system id
   u   change display/entry units
   v   verify the partition table
   w   write table to disk and exit
   x   extra functionality (experts only)
 
Command (m for help): p
 
Disk /dev/sdc: 21.5 GB, 21474836480 bytes
255 heads, 63 sectors/track, 2610 cylinders, total 41943040 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x2a749bbb
 
   Device Boot      Start         End      Blocks   Id  System
 
Command (m for help): n  
Partition type:
   p   primary (0 primary, 0 extended, 4 free)
   e   extended
Select (default p): p
Partition number (1-4, default 1): 1
First sector (2048-41943039, default 2048):
Using default value 2048
Last sector, +sectors or +size{K,M,G} (2048-41943039, default 41943039):
Using default value 41943039
 
Command (m for help): w
The partition table has been altered!
 
Calling ioctl() to re-read partition table.
Syncing disks.

And build Linux file sytem in new hard disk (I chose ext4)

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mkfs -t ext4 /dev/sdb1

And try to mount new hard disk to directory

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mkdir /var/data
mount /dev/sdb1 /var/data

Test with df command

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thanhson1085@sonnst:~$ df -h
Filesystem                   Size  Used Avail Use% Mounted on
/dev/mapper/sonnst--vg-root   39G   32G  4.7G  87% /
none                         4.0K     0  4.0K   0% /sys/fs/cgroup
udev                         483M  4.0K  483M   1% /dev
tmpfs                         99M  676K   99M   1% /run
none                         5.0M     0  5.0M   0% /run/lock
none                         494M     0  494M   0% /run/shm
none                         100M     0  100M   0% /run/user
/dev/sda1                    236M   37M  188M  17% /boot
/dev/sdb1                     40G  4.7G   33G  13% /var/data

Finally, add the mount to fstab to automatically mount disk when system start.

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sudo vi /etc/fstab

Add line:

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/dev/sdb1       /var/data  ext4    rw,user,auto,exec 0       0

To apply the new change of fstab file. We use command:

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mount -a

In case the automation fails, you can troubleshoot with command:

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sudo vi /var/log/syslog
sudo dmesg|grep mount

A error case:

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thanhson1085@sonnst:~$ sudo dmesg | grep mount
1531:[    2.587995] EXT4-fs (dm-0): mounted filesystem with ordered data mode. Opts: (null)
1542:[   10.259551] EXT4-fs (dm-0): re-mounted. Opts: errors=remount-ro
1556:[   10.503269] EXT4-fs (sda1): mounting ext2 file system using the ext4 subsystem
1557:[   10.547261] EXT4-fs (sda1): mounted filesystem without journal. Opts: (null)
1558:[   10.553733] EXT4-fs (sdb4): Unrecognized mount option "utf8" or missing value

 

Nguyen Sy Thanh Son

1

Linux, PHP

Install Memcached, PHP Memcache and PHP Memcached in Ubuntu 14.04

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As you know, Memcached is great cache system for your web application. Use correctly Memcached will speed up your application so much. So now is how to install memcached, PHP Memcache and PHP Memcached

Install Memcached, PHP Memcache and PHP Memcached in Ubuntu 14.04

In Ubuntu 14.04, the installation is very simple, just need one command:

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sudo apt-get install memcached php5-memcache php5-memcached

Please remember restart apache2:

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sudo /etc/init.d/apache2 restart

Finally, test your works by writing some PHP scripts.

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vi test.php

Add php script to test.php:

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<?php
 
$memcache = new Memcache();
$memcache->connect('localhost', 11211);
 
$memcache->set('test', false); //
$flags = false;
var_dump($memcache->get('test', $flags)); // bool(false)
var_dump($flags); // int(256) - changed to int
 
$memcache->delete('test');
 
$flags = false;
var_dump($memcache->get('test', $flags)); // bool(false)
var_dump($flags); // bool(false) - untouched
 
?>

Successful result:

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thanhson1085@sonnst:~$ php test.php
bool(false)
int(256)
bool(false)
bool(false)

 

 

Nguyen Sy Thanh Son

1

Linux

Send email with Postfix in Ubuntu

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As you know, to install a email server, you should install both Postfix and Dovecot, in this case it is quite complicated.  In case you just need run sendmail function of Postfix, you should install PostFfix and config to relay to a SMTP server that you have.  So in this article, I will show you steps to install and config it.

The scenario of this example as below:

You have a smtp server with configuration information as below

Firstly, install Postfix:

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sudo apt-get install  postfix

Open /etc/postfix/main.cf change some parameters as below:

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myhostname = your_domain_here #eg: example.com
alias_maps = hash:/etc/aliases
alias_database = hash:/etc/aliases
mydestination = your_domain_here, localhost, localhost.localdomain
relayhost = url_smtp_server:port #e.g: smtp.example.com:25
smtp_sasl_auth_enable = yes
smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd
smtp_sasl_security_options = noanonymous
mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
mailbox_size_limit = 0

And create /etc/postfix/sasl_passwd file and add content below

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url_smtp_server:port  username:password

Type below comand to create sasl_passwd.db:

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sudo postmap /etc/postfix/sasl_passwd

Restart Postfix:

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sudo /etc/init.d/postfix restart

Finally, test send email (make sure that you installed mail client):

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echo "Test mail from postfix" | mail -s "Test Postfix" your_email@gmail.com

You are done.

In case having errors, you can check log with command:

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sudo tail -f /var/log/syslog

And now,  you can write a php script, use Swiftmailer library to test send email via transport sendmail

Nguyen Sy Thanh Son

0

Linux

Send mail in Ubuntu server with Gmail SMTP

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In a web project, email function is quite important thing.  For sending email you can use a free SMTP server or sendmail function in your server. So how to send mail in Ubuntu server? The answer is Postfix or SSMTP.  But SSMTP is simper way. Because all we have a free smtp server (e.g Gmail SMTP), and also SSMTP is easier to install.

A wise man never knows all, only fools know everything

A wise man never knows all, only fools know everything

Now, you install SSMTP packet:

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sudo apt-get install ssmtp

And open the config file:

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sudo vi /etc/ssmtp/ssmtp.conf

Add new content as below (do not forget change your_emal and your_gmail_password, your_gmail_username):

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Root=your_email@gmail.com
Mailhub=smtp.gmail.com:465
RewriteDomain=gmail.com
AuthUser=your_gmail_username # (before the @gmail.com part)
AuthPass=your_gmail_password
FromLineOverride=Yes
UseTLS=Yes

(It seems that Gmail is more secure, so you have to enable less secure to use SMTP Gmail https://www.google.com/settings/security/lesssecureapps)

To test, you need install send mail client:

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sudo apt-get install heirloom-mailx

Finally, do a test:

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echo testing|mail -s 'Test Mail' email_to@gmail.com

You are a PHP developer, the server now can run mail php function. However, you are using Swiftmailer Library, you will got a error message as below:

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Expected response code 220 but got code "", with message ""

Because Swiftmailer always try to telnet to localhost to check mail server before sending mail. But SSMTP does not support telnet.

So It is time to use Postfix, I will have a article to so you some tips to install it.

Nguyen Sy Thanh Son

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