How to create a new Docker image?

maxresdefaultIn this article we’re going to build one new docker image with Apache and PHP installed and one php file for test.

Create a directory called “build”:

# mkdir ˜/build

Change to directory “build”:

# cd ˜/build

Create a new file called Dockerfile with the following content:

FROM centos
MAINTAINER Daniel Nascimento
RUN yum update -y
RUN yum install httpd php -y
ADD index.php /var/www/html/
CMD /usr/sbin/apachectl -D FOREGROUND
EXPOSE 80

In the same directory create another file called index.php with the following content:



Finally it’s time of build our new image.

# docker build -t user/httpd .

Now we have a new image with apache and php installed. Then let’s create a new container using this image:

# docker run -t -i -p 80:80 user/httpd

To access our new container in your browser type the URL:

http://your-host-ip/

That’s it! :-)

How to Install and set up GitHub on Centos 7

First let’s install Git:

# yum install git -y

Use the follow commands to add in the required information:

$ git config --global user.name "NewUser"
$ git config --global user.email newuser@example.com

Create a directory called myproject for our workspace environment:

$ mkdir myproject/

Change to directory myproject/.

$ cd myproject/

Create a new file called teste.txt

$ touch teste.txt

Initialized a new empty repository:

$ git init

Add the file created early called teste.txt to the new created repository:

$ git add teste.txt (Add only file teste.txt)

or

$ git add . (Add all files)

To commit the changes, use the command:

$ git commit -m “Explaining the changes” -a (To commit all files)

or

$ git commit -m “Explaining the changes” teste.txt (To commit only file teste.txt)

Pushing changes to a remote server

To add a new remote repository, use the command:

$ git remote add origin git@github.com:user/myproject.git

To push your local repository to a remote repository use the command:

$ git push origin master

Reference: https://github.com/

How to disable telnet in AIX

By default the  telnet service is enable in AIX and SSH is not installed, if you installed the SSH, so can you disable telnet service follow below steps:

Open the file /etc/inetd.conf:

# vi /etc/inetd.conf

Comment out the line below to disable to telnet service:

#telnet  stream  tcp6    nowait  root    /usr/sbin/telnetd      telnetd -a

Save it and reload inetd:

# refresh -s inetd

LVM – How to migrate data between disks?

Environment:

Red Hat Enterprise Linux Server 6.0

Case:

You have a server connected in storage A and need migrate the data to new storage B.

How to migrate data between disks with the server online?

In this article I will explain how migration of data between the disks, without unavailability, remember that in our example we’re using LVM.

This article assumes that the new disk has been installed on the system and is visible to the operating system as /dev/sdb.

Create a new partition of type LVM in new disk:

Create a new PV:

# pvcreate /dev/sdb1

Add the new PV to VG:

# vgextend VG_NAME /dev/sdb1

Move data between disks with command:

# pvmove -v /dev/sda1

The command pvmove will move data from disk sda1 to sdb1:

Check if the PV was released with command:

# pvs

Now remove the old disk from the VG with command:

# vgreduce -a

The option -a remove from VG all the PV free. In our exemple the disk sda1.

Now the disk can be removed from the server.

AIX – How to install ProFTP in AIX

This article I explain how to install ProFTP in AIX 6.1, limiting the access only to user home directory.

Environment

AIX 6.1
ProFTP 1.2.8
FileUtils 4.1.4

Download

The package needed can be downloaded in link below:

ftp://ftp.software.ibm.com/aix/freeSoftware/aixtoolbox/RPMS/ppc/proftpd/proftpd-1.2.8-1.aix5.1.ppc.rpm

The package File Utils is required to install ProFTP, below the link to downloaded if not installed:

ftp://ftp.software.ibm.com/aix/freeSoftware/aixtoolbox/RPMS/ppc/fileutils/fileutils-4.1-4.aix4.3.ppc.rpm

Install

Install FileUtils if required:

# rpm -ivh fileutils-4.1-4.aix4.3.ppc.rpm fileutils ##################################################

Install ProFTP:

# rpm -ivh proftpd-1.2.8-1.aix5.1.ppc.rpm proftpd ##################################################

Configure

Now, let’s configure proftp.

To create jail for users uncomment the line “#DefaultRoot ~” in the file /etc/proftpd.conf to:

DefaultRoot ~

To start ProFTP by inetd, change the line “ServerType standalone” in the file /etc/proftpd.conf to:

ServerType inetd

Then, in file /etc/inetd.conf change the line below:

From:

ftp stream tcp6 nowait root /usr/sbin/ftpd ftpd

To:

ftp stream tcp nowait root /usr/sbin/proftpd proftpd -p enable

Make sure that the User “nobody” and the group “nogroup” exist on your system. In my case I changed  the group to “staff”.

In the file /etc/proftpd.conf change the group to:

Group staff

Now, let’s start the ProFTPD with command:

#startsrc -t ‘ftp’

Linux – How to find duplicate IP address?

This is a quick tip to find duplicate IP address in your local LAN network.

To find duplicate IP address, you can use arping command under linux.

Example:

#arping -D 192.168.0.10

Output:

# arping -D 192.168.0.10 132

ARPING 192.168.0.10 from 192.168.0.2 eth0

Unicast reply from 192.168.0.10 [00:0C:29:2A:3C:C7]  0.896ms

Unicast reply from 192.168.0.10 [00:0C:29:55:B7:DB]  0.923ms

Where the option -D mean: duplicate address detection mode.

In our example there is duplicate IP address in local LAN network.

How to find WWN(World Wide Name) of a fibre-channel in IBM AIX

To find the WWN (world wide name) of a fibre-channel in IBM AIX use the command below:

# lscfg -vp -l fcs0 | grep “Network Address”

Output:

Network Address…………. 10000000C980DBE8

Where 10000000C980DBE8 is world wide name.

Another way to find WWN is using the command:

# fcstat fcs0 | grep “World Wide Port Name”

Output:

World Wide Port Name: 0x10000000C980DBE8

Where 0x10000000C980DBE8 is world wide name.