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Instalasi Xen Hypervisor pada Debian Wheezy

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Xen Hypervisor

Xen is an open-source (GPL) type-1 or baremetal hypervisor, which makes it possible to run many instances of an operating system or indeed different operating systems in parallel on a single machine (or host).
Here are some of the Xen Project hypervisor’s key features:

  • Small footprint and interface (is around 1MB in size). Because it uses a microkernel design, with a small memory footprint and limited interface to the guest, it is more robust and secure than other hypervisors.
  • Operating system agnostic: Most installations run with Linux as the main control stack (aka “domain 0”). But a number of other operating systems can be used instead, including NetBSD and OpenSolaris.
  • Driver Isolation: The Xen Project hypervisor has the capability to allow the main device driver for a system to run inside of a virtual machine. If the driver crashes, or is compromised, the VM containing the driver can be rebooted and the driver restarted without affecting the rest of the system.
  • Paravirtualization: Fully paravirtualized guests have been optimized to run as a virtual machine. This allows the guests to run much faster than with hardware extensions (HVM). Additionally, the hypervisor can run on hardware that doesn’t support virtualization extensions.

Guest types
Xen supports running two different types of guests: Paravirtualization (PV) and Full or Hardware assisted Virtualization (HVM). Both guest types can be used at the same time on a single Xen system. It is also possible to use techniques used for Paravirtualization in an HVM guest: essentially creating a continuum between PV and HVM. This approach is called PV on HVM. See the Xen Overview on the Xen wiki for more information.

Domain 0
Xen has a special domain called domain 0 which contains drivers for the hardware, as well as the toolstack to control VMs. Domain 0 is often referred to as dom0. Before installing Xen you should install Debian on the host machine. This installation will form the basis of Domain 0.

Xen Architecture

Xen Architecture

Referensi:

  1. Xen
  2. Xen Project Software Overview

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Written by awarmanf

September 7, 2016 at 3:30 am

Posted in Linux, virtualization, xen

SMS Gateway dengan Perl

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SMS Gateway

Pada pertengahan tahun 2005 penulis mengerjakan proyek SMS Gateway untuk proses perhitungan suara pada Pilkada di Jember. Pada saat itu penulis menggunakan aplikasi SMS Server Tool (smstools) dan modem GSM Siemens MC35i dan TC35i. Harganya per biji waktu itu 2,1 juta.

Modem GSM Siemens

Modem GSM Siemens

Dibandingkan dengan aplikasi sms server saat ini seperti kannel atau gammu, smstools sangatlah sederhana. Aplikasi smstools-1.14.3.tar.gz yang saat itu penulis pakai hanya mempunyai fitur konfigurasi sms. Untuk pengolahan sms yang masuk dilakukan melalui script programming seperti bash atau perl begitu pula untuk menyimpan sms ke dalam database seperti MySQL.


Modem GSM

Beberapa tahun kemudian penulis mendapatkan tugas di kantor membuat SMS Gateway untuk broadcast sms internal ke staff kantor baik pusat maupun cabang. Dengan memperhatikan kepraktisan dan kemudahan penulis menggunakan kannel dan playSMS sedangkan modem gsm menggunakan “Wavecom Fast Track” dengan koneksi serial.

Wavecom Fast Track

Wavecom Fast Track


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Written by awarmanf

August 18, 2016 at 2:42 pm

Setup Free Radius dengan Autentikasi ke OpenLDAP

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Topologi

Topologi radius openldap

Topologi radius openldap


Server dan Router:

  1. OpenLDAP
    • ether0: 192.168.1.2
  2. Radius Server
    • ether0: 192.168.1.3
  3. Mikrotik
    • ether1: 192.168.1.1
    • ether2: 192.168.10.1

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Written by awarmanf

January 6, 2015 at 2:24 am

Membuat Account Nomail di Zimbra LDAP

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Jika menggunakan Zimbra LDAP + Samba PDC sebagai database user terpusat (Single Sign On) untuk autentikasi user Linux maupun Windows ada kalanya kita ingin buat account khusus yang tidak punya akses email (nomail) melainkan hanya untuk login domain dan akses ke file sharing. Contohnya account staff atau karyawan yang memang tidak mempunyai fasilitas alamat email perusahaan, account system yang hanya memerlukan login domain, atau pun account tamu seperti vendor atau konsultan yang membutuhkan akses sementara ke file server.

Pembuatan account model ini tidak bisa dilakukan melalui menu create account di zimbra admin console melainkan melalui perintah ldap.

Contoh Directory Information Tree (DIT) organisasi yang kita gunakan untuk kasus ini:

Contoh DIT

Contoh DIT


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Written by awarmanf

January 6, 2015 at 2:22 am

Posted in Uncategorized

Ubah Password LDAP Root Zimbra

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Sewaktu masih menggunakan zimbra versi 6.x penggantian password ldap root dilakukan dengan perintah:

[zimbra@server ~]$ zmldappasswd -r newpassword
Updating local config and LDAP


Namun usai upgrade zimbra ke versi 7.2.1 ternyata penggantian password ldap root tidak bisa dilakukan dengan cara demikian. Saat dilakukan penggantian password muncul error seperti di bawah ini:

[zimbra@server ~]$ zmldappasswd -r newpassword
Updating local config and LDAP
TLS: SSL connect attempt failed with unknown errorerror:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed

Penulis sudah googling namun tidak menemukan solusi untuk masalah di atas.
Akhirnya setelah membaca manual LDAP, masalah di atas dipecahkan dengan cara ubah password melalui perintah ldapmodify secara interaktif. Sebagaimana kita ketahui ldap root itu adalah user root atau dn: cn=config LDAP (dn: distinguished name).
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Written by awarmanf

January 6, 2015 at 2:18 am

Posted in LDAP, Linux, zimbra

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Backup Email Secara Live – 2

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Pada tulisan sebelumnya telah dibahas strategi atau langkah-langkah untuk backup email secara live dengan menggunakan MTA Postfix + Courier-Imap + Courier-Authlib sebagai Mail Server Backup. Selanjutnya pada tulisan ini akan dibahas backup email menggunakan Zimbra Open Source Edition.

Schema Live Email Backup

Schema Live Email Backup

Secara garis besar adalah sebagai berikut:

  • Backup email user dilakukan secara transparent dengan membuat rule sender_bcc dan recipient_bcc di konfigurasi postfix Server Mail.
  • Setup Server Mail Backup dengan Zimbra Open Source Edition untuk menerima trafik backup email incoming dan outgoing dari Server Mail.
  • Setup email filtering di account email user yang akan dibackup untuk menyimpan berkas email masuk ke folder Inbox dan Sent.

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Written by awarmanf

January 6, 2015 at 2:13 am

Posted in LDAP, Linux, postfix, zimbra

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Create OpenVZ RHEL 5.5 Template With Minimal Xwindows

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This guide is a reference on how to create a Red Hat Enterprise Linux v5.5 64bit template for OpenVZ. The template will support for running xwindows applications using twm (Tab Window Manager). TWM is a window manager for the X Window System, a small program, being built against Xlib rather than using a widget library, and as such, it is very light on system resources. Though simple, it is highly configurable; fonts, colours, border widths, title bar buttons, etc. can all be set by the user.


RHEL 5.5 Installation

Install RHEL 5.5 at physical server using text mode. We do the minimum installation.

  • Do not modify LVM just install as usual.
  • Do not enable selinux.
  • Disable firewall.
  • At the package group selection just select Core and Base.

After installing, boot the server and mount RHEL 5.5 DVD at /media/RHEL5.5.

We are using the RHEL 5.5 DVD as a yum repository. So create file /etc/yum.repos.d/rhel-dvd.repo

[dvd]
name=Red Hat Enterprise Linux Installation DVD
baseurl=file:///media/RHEL5.5/Server
enabled=0
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-redhat-release

The attribut gpg copied from /etc/yum.repos.d/rhel-debuginfo.repo.
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Written by awarmanf

December 12, 2014 at 3:58 am

Posted in centos, Linux, openvz

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