Browsing the archives for the iT tag.

LaTeX on Debian 8

ai-tee, linux

TeX Live Installation

$ sudo apt-get install texlive-full
$ http://download.opensuse.org/repositories/home:/jsundermeyer/Debian_8.0/amd64/texstudio_2.12.4-3.1_amd64.deb

TeXstudio installation

$ sudo dpkg -i texstudio_2.12.4-3.1_amd64.deb
$ sudo apt-get install -f

Texmaker installation

$ sudo dpkg -i texmaker_debian_jessie_4.5_amd64.deb
$ sudo apt install -f

Sublime installation

$ wget https://download.sublimetext.com/sublime-text_build-3126_amd64.deb
$ sudo dpkg -i sublime-text_build-3126_amd64.deb

Source:

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Neo4j Installation on Linux Debian 8

ai-tee, graph-database

Installing Java 8

$ sudo apt-get install software-properties-common
$ sudo add-apt-repository "deb http://ppa.launchpad.net/webupd8team/java/ubuntu xenial main"
$ sudo apt-get update
$ sudo apt-get install oracle-java8-installer

Installing Neo4j 3.20 Community Edition

$ wget -O - https://debian.neo4j.org/neotechnology.gpg.key | sudo apt-key add -

$ echo 'deb http://debian.neo4j.org/repo stable/' | sudo tee -a /etc/apt/sources.list.d/neo4j.list
$ sudo apt-get update
$ sudo apt-get install neo4j=3.2.0

Source(s):

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Wildcard SSL Certificate Installation on Zimbra Mail Server

ai-tee, linux

Prepare the necessary files:

  • commercial.key
    Contains private key that is used to generate CSR (for a wildcard certificate, this private key can be from another machine from a same domain)
  • commercial.crt
    Contains a commercial SSL certificate that is generated by a CA, such as “RapidSSL Wildcard certificate” in my case
  • ca_bundle.crt
    Contains CA’s bundle such as “RapidSSL/Wildcard SHA-2 under SHA-1 root” from https://www.namecheap.com/support/knowledgebase/article.aspx/9393/69/where-do-i-find-ssl-ca-bundle)

Installation steps:

# su zimbra
$ ls /opt/zimbra/ssl/zimbra/commercial/
commercial.key
$ ls /tmp/ssl/
ca_bundle.crt  commercial.crt
$ zmcertmgr verifycrt comm /opt/zimbra/ssl/zimbra/commercial/commercial.key /tmp/ssl/commercial.crt /tmp/ssl/ca_bundle.crt
** Verifying '/tmp/ssl/commercial.crt' against '/opt/zimbra/ssl/zimbra/commercial/commercial.key'
Certificate '/tmp/ssl/commercial.crt' and private key '/opt/zimbra/ssl/zimbra/commercial/commercial.key' match.
** Verifying '/tmp/ssl/commercial.crt' against '/tmp/ssl/ca_bundle.crt'
Valid certificate chain: /tmp/ssl/commercial.crt: OK
$ zmcertmgr deploycrt comm /tmp/ssl/commercial.crt /tmp/ssl/ca_bundle.crt
...
** Copying '/tmp/ssl/commercial.crt' to '/opt/zimbra/ssl/zimbra/commercial/commercial.crt'
** Copying '/tmp/ssl/ca_bundle.crt' to '/opt/zimbra/ssl/zimbra/commercial/commercial_ca.crt'
** Appending ca chain '/tmp/ssl/ca_bundle.crt' to '/opt/zimbra/ssl/zimbra/commercial/commercial.crt'
** Importing cert '/opt/zimbra/ssl/zimbra/commercial/commercial_ca.crt' as 'zcs-user-commercial_ca' into cacerts '/opt/zimbra/common/lib/jvm/java/jre/lib/security/cacerts'
** NOTE: restart mailboxd to use the imported certificate.
...
$ zmcontrol restart
$ zmcertmgr viewdeployedcrt

Verification:

Verify using https://www.ssllabs.com/ssltest/

Source:

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Optimizing Debian on Laptop

ai-tee, linux

TLP (advanced power management for Linux)

# echo "deb http://ftp.debian.org/debian jessie-backports main" >> /etc/apt/sources.list
# apt-get update
# apt-get install tlp tlp-rdw
# tlp start
# tlp-stat -s

Source:


Brightness Adjusment

Create a script:

# vim brightness.sh
# chmod +x brightness.sh

Content of “brightness.sh” script

function main_menu
{
    sudo clear
    cursetting=$(cat /sys/class/backlight/intel_backlight/brightness)
    maxsetting=$(cat /sys/class/backlight/intel_backlight/max_brightness)
    powersave=$((maxsetting/5))
    conservative=$((powersave*2))
    medium=$((powersave*3))
    performance=$((powersave*4))
    echo ""
    echo "----------------------- Brightness -----------------------"
    echo " 1. Set Display to Minimum (Powersave) brightness setting."
    echo " 2. Set Display to Low (Conservative) brightness setting."
    echo " 3. Set Display to Medium brightness setting."
    echo " 4. Set Display to High (Performance) brightness setting."
    echo " 5. Set Display to Maximum brightness setting."
    echo " 6. Exit."
    echo "----------------------------------------------------------"
    if [ $cursetting -eq $powersave ]; then
     cursetting='Minimum'
    else
     if [ $cursetting -eq $conservative ]; then
      cursetting='Conservative'
     else
      if [ $cursetting -eq $medium ]; then
       cursetting='Medium'
      else
       if [ $cursetting -eq $performance ]; then
        cursetting='Performance'
       else
        if [ $cursetting -eq $maxsetting ]; then
         cursetting='Maximum'
        fi
       fi
      fi
     fi
    fi
    echo "        Current Display Setting - "$cursetting;
    choice=7
    echo ""
    echo -e "Please enter your choice: \c"
}

function press_enter
{
    echo ""
    echo -n "Press Enter to continue."
    read
    main_menu
}

main_menu
while [ $choice -eq 7 ]; do
read choice

if [ $choice -eq 1 ]; then
 echo $powersave | sudo tee /sys/class/backlight/intel_backlight/brightness
 main_menu
else
 if [ $choice -eq 2 ]; then
  echo $conservative | sudo tee /sys/class/backlight/intel_backlight/brightness
  main_menu
 else
  if [ $choice -eq 3 ]; then
   echo $medium | sudo tee /sys/class/backlight/intel_backlight/brightness
   main_menu
  else
   if [ $choice -eq 4 ]; then
    echo $performance | sudo tee /sys/class/backlight/intel_backlight/brightness
    main_menu
   else
    if [ $choice -eq 5 ]; then
     echo $maxsetting | sudo tee /sys/class/backlight/intel_backlight/brightness
     main_menu
    else
     if [ $choice -eq 6 ]; then
      exit;
     else
      echo -e "Please enter the NUMBER of your choice: \c"
      choice = 7
     fi
    fi
   fi
  fi
 fi
fi
done

Source


Add Sudo user

# apt-get install sudo
# adduser [new-user]
# adduser [new-user] sudo

If it is still failed, add the [new-user] directly with visudo

# visudo
Add the [new-user] on this section # User privilege specification
root ALL=(ALL:ALL) ALL
[new-user] ALL=(ALL:ALL) ALL

Source:


UTC or Local Time Management

Synchronizing UTC or local time between two OS (Windows and Linux) in dual boot Laptop.

$ sudo timedatectl
      Local time: Thu 2017-05-11 21:42:06 WIB
  Universal time: Thu 2017-05-11 14:42:06 UTC
        RTC time: Thu 2017-05-11 14:42:06
       Time zone: Asia/Jakarta (WIB, +0700)
     NTP enabled: yes
NTP synchronized: yes
 RTC in local TZ: no
      DST active: n/a
$ sudo timedatectl set-local-rtc 1
$ sudo timedatectl
      Local time: Thu 2017-05-11 21:45:00 WIB
  Universal time: Thu 2017-05-11 14:45:00 UTC
        RTC time: Thu 2017-05-11 21:45:00
       Time zone: Asia/Jakarta (WIB, +0700)
     NTP enabled: yes
NTP synchronized: yes
 RTC in local TZ: yes
      DST active: n/a

Source:


Remote Desktop Protocol

$ sudo apt-get install rdesktop

Source:


TeamViewer

$ wget https://downloadus1.teamviewer.com/download/version_12x/teamviewer_12.0.76279_i386.deb
$ sudo dpkg -i teamviewer_12.0.76279_i386.deb
$ sudo apt-get install -f

Source:


Improve Font Rendering

Subpixel-hinting and Font-smoothing
Create a file “.fonts.conf” in the home folder

$ more ~/.fonts.conf
<?xml version='1.0'?>
<!DOCTYPE fontconfig SYSTEM 'fonts.dtd'>
<fontconfig>
 <match target="font">
  <edit mode="assign" name="rgba">
   <const>rgb</const>
  </edit>
 </match>
 <match target="font">
  <edit mode="assign" name="hinting">
   <bool>true</bool>
  </edit>
 </match>
 <match target="font">
  <edit mode="assign" name="hintstyle">
   <const>hintslight</const>
  </edit>
 </match>
 <match target="font">
  <edit mode="assign" name="antialias">
   <bool>true</bool>
  </edit>
 </match>
  <match target="font">
    <edit mode="assign" name="lcdfilter">
      <const>lcddefault</const>
    </edit>
  </match>
</fontconfig>

Install Infinality

$ more /etc/apt/sources.list
...
deb http://ppa.launchpad.net/no1wantdthisname/ppa/ubuntu trusty main
deb-src http://ppa.launchpad.net/no1wantdthisname/ppa/ubuntu trusty main
...
$ sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys E985B27B
$ sudo apt-get update
$ sudo apt-get install fontconfig-infinality
$ sudo bash /etc/fonts/infinality/infctl.sh setstyle
Select a style:
1) debug       3) linux          5) osx2         7) win98
2) infinality  4) osx          6) win7         8) winxp
#? 3
conf.d -> styles.conf.avail/linux
$ more /etc/profile.d/infinality-settings.sh
...
# USE_STYLE="DEFAULT"
USE_STYLE="UBUNTU"
...

Install Ubuntu Font

$ wget http://mirrors.kernel.org/ubuntu/pool/main/u/ubuntu-font-family-sources/ttf-ubuntu-font-family_0.80-0ubuntu6_all.deb
$ sudo dpkg -i ttf-ubuntu-font-family*.deb
$ sudo apt-get install gnome-tweak-tool
$ gnome-tweak-tool

Configure Fonts on gnome-tweak-tool:

  • Window Titles [ Ubuntu Regular – 11 ]
  • Interface [ Ubuntu Regular – 11 ]
  • Documents [ Ubuntu Regular – 11 ]
  • Monospace [ Ubuntu Mono Regular – 13 ]
  • Hinting [ Slight ]
  • Antialiasing [ Rgba ]
  • Scaling Factor [ 1.00 ]

Install Microsoft Font

$ sudo apt-get install ttf-mscorefonts-installer
$ wget http://download.microsoft.com/download/E/6/7/E675FFFC-2A6D-4AB0-B3EB-27C9F8C8F696/PowerPointViewer.exe
$ unar PowerPointViewer.exe
$ cd PowerPointViewer/
$ unar ppviewer.cab
$ cd ppviewer/
$ mkdir ~/.fonts
$ cp *.TTF *.TTC ~/.fonts

Logout and login again to see the change.

Source:


Browser

Chrome install

$ wget https://dl.google.com/linux/direct/google-chrome-stable_current_amd64.deb
$ sudo dpkg -i google-chrome-stable_current_amd64.deb

Source:


Show Desktop

Settings => Keyboard => Shortcut => Navigation => Hide all normal windows (Super + D)

Source:


Printer Management

$ sudo apt install cups

Open http://localhost:631/admin

Source:


Change Python Version 2 to 3

$ ls /usr/bin/python*
/usr/bin/python3.4 /usr/bin/python2.7
$ python --version
Python 2.7.9
$ sudo update-alternatives --list python
update-alternatives: error: no alternatives for python
$ sudo update-alternatives --install /usr/bin/python python /usr/bin/python2.7 1
update-alternatives: using /usr/bin/python2.7 to provide /usr/bin/python (python) in auto mode
$ sudo update-alternatives --install /usr/bin/python python /usr/bin/python3.4 2
update-alternatives: using /usr/bin/python3.4 to provide /usr/bin/python (python) in auto mode
$ python --version
Python 3.4.2

Back again to version 2 or vice versa:

$ sudo update-alternatives --config python
There are 2 choices for the alternative python (providing /usr/bin/python).
Selection Path Priority Status
------------------------------------------------------------
* 0 /usr/bin/python3.4 2 auto mode
 1 /usr/bin/python2.7 1 manual mode
 2 /usr/bin/python3.4 2 manual mode
Press enter to keep the current choice[*], or type selection number: 

Sources:

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Upgrading Debian Wheezy (7) to Jessie (8)

linux

I’ve just upgraded a Debian server from Wheezy to Jessie with these steps:

# apt-get update && apt-get upgrade && apt-get dist-upgrade
# dpkg --audit && dpkg --get-selections | grep hold
# vim /etc/apt/sources.list
[add these list - for Indonesian user]
deb http://kambing.ui.ac.id/debian/ jessie main contrib non-free
deb-src http://kambing.ui.ac.id/debian/ jessie main contrib non-free
deb http://kambing.ui.ac.id/debian/ jessie-updates main contrib non-free
deb-src http://kambing.ui.ac.id/debian/ jessie-updates main contrib non-free
deb http://security.debian.org/ jessie/updates main contrib non-free
deb-src http://security.debian.org/ jessie/updates main contrib non-free
# apt-get update && apt-get upgrade && apt-get dist-upgrade
# more /etc/debian_version && more /etc/os-release
# reboot

Add apache-mysql-php:

# apt-get install mysql-server mysql-client
# apt-get install apache2 apache2-doc
# apt-get install php5 libapache2-mod-php5 php5-mysql
# service apache2 restart

Source:
https://www.howtoforge.com/tutorial/how-to-upgrade-debian-wheezy-to-jessie-stable-release/

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Configure SSH Access on Cisco IOS

router

How to configure SSH access on Cisco IOS (switch or router):

1. Setting hostname and domain-name

switch# configure terminal
switch(config)#hostname catalyst
catalyst(config)#ip domain-name itmaranatha.org

2. Generate RSA keys (use 1024 bit for SSHv2 enabled)

catalyst(config)#crypto key generate rsa

3. Configure line vty

catalyst(config)#line vty 0 15
catalyst(config-line)#login local
catalyst(config-line)#transport input ssh

4. Create local user/pass

catalyst(config)#username [user] privilege 15 secret [password]

5. Fine tuning

catalyst(config)#line vty 0 15
catalyst(config-line)#exec-timeout 5
catalyst(config-line)#exit
catalyst(config)#ip ssh version 2

 

Source:
https://www.pluralsight.com/blog/tutorials/configure-secure-shell-ssh-on-cisco-router

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Error Restarting Network Service in CentOS 7

linux

Today I got this error message when restarting network service with # systemctl restart network.service or # service network restart:

Restarting network (via systemctl): Job for network.service failed. See 'systemctl status network.service' and 'journalctl -xn' for details.

Browsing around for a while, then found this solution:

# systemctl stop NetworkManager
# systemctl disable NetworkManager

After disabling NetworkManger, restarting network service succeeded.

Source:
http://unix.stackexchange.com/questions/220750/centos-7-failed-to-bring-up-down-networking-configure-interface-for-a-trunk-in
http://www.linuxquestions.org/questions/linux-newbie-8/centos-7-failed-to-bring-up-down-networking-configure-interface-for-a-trunk-interfa-4175550117/

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All-in-One Software Defined Network (SDN) VM

SDN

If you want to jumpstart learning SDN without installing every single software on operating system, Srini Seetharaman has all-in-one VM that already installed with necessary SDN learning software.

The sofware and tools installed on the VM (listed by SDNhub.org):

  • SDN Controllers: OpenDaylight, ONOS, RYU, Floodlight, Floodlight-OF1.3, POX, and Trema
  • Example code for a hub, L2 learning switch, traffic tap, and other applications
  • Open vSwitch 2.3.0 with support for Openflow 1.2, 1.3 and 1.4, and LINC switch
  • Mininet to create and run example topologies
  • Pyretic
  • Wireshark 1.12.1 with native support for OpenFlow parsing
  • JDK 1.8, Eclipse Luna, and Maven 3.3.3

These are the instruction steps:

  1. Install VirtualBox or Vmware Player/Fusion
  2. Install Putty and Xming (for Windows) or Xquartz (for Mac)
  3. Download appliance from one of these link:
    http://yuba.stanford.edu/~srini/tutorial/SDN_tutorial_VM_32bit.ova
    http://yuba.stanford.edu/~srini/tutorial/SDN_tutorial_VM_64bit.ova
  4. Import downloaded file (SDN_tutorial_VM_XXbit.ova) to VirtualBox or Vmware Player/Fusion
  5. Start the VM (user/password: ubuntu/ubuntu)

Source:
http://sdnhub.org/tutorials/sdn-tutorial-vm/
http://yuba.stanford.edu/~srini/Beginners_OpenFlowTutorial_Meetup_June_2013.pptx

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Apt-get update error

linux, server

As Debian big fan, sometime I found that apt-get update command reveal this error:
“E: Some index files failed to download. They have been ignored, or old ones used instead.”

This command is very simple solution I found:

# rm /var/lib/apt/lists/partial/*

After that, apt-get update && apt-get upgrade command should be fine.

Source:
http://forums.debian.net/viewtopic.php?f=10&t=108618

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SSH Server Administration

linux, server

Having several Linux Servers, SSH access is mandatory communication between me and those servers. These are several tips for SSH Server administration that save the day:

Add these line on /etc/ssh/sshd_config:

  • Allow only specific user (never use root login for remote SSH access)
    AllowUsers username
    DenyUsers All
  • Disable DNS and GSSAPI (solving slow login respond, especially from private network)
    UseDNS no
    GSSAPIAuthentication no

Make sure to restart SSH service after changing sshd_config:

# service ssh restart

or

# /etc/init.d/ssh restart

Additional tip:

  • Add this options on /etc/resolv.conf (solving slow login respond on RHEL/CentOS)
options single-request-reopen

Source:

http://injustfiveminutes.com/2013/03/13/fixing-ssh-login-long-delay/

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