Convert .p12 bundle to server certificate and key files

Seperate Private Key and Certificate file

#Generate certificates bundle file

openssl pkcs12 -nokeys -in server-cert-key-bundle.p12 -out server-ca-cert-bundle.pem

#Generate server key file

openssl pkcs12 -nocerts -nodes -in server-cert-key-bundle.p12 -out server.key

Convert a PKCS#12 file (.pfx .p12) containing a private key and certificates to PEM

openssl pkcs12 -in keyStore.pfx -out keyStore.pem -nodes



ওমরাহর নিয়ম

১. ওমরাহর ইহরাম (ফরজ)
· পরিষ্কার-পরিচ্ছন্নতা সেরে গোসল বা অজু করে নিতে হবে
· মিকাত অতিক্রমের আগেই সেলাইবিহীন একটি সাদা কাপড় পরিধান করুন, অন্যটি গায়ে জড়িয়ে নিয়ে ইহরামের নিয়তে দুই রাকাত নামাজ পড়ে নিন
· শুধু ওমরাহর নিয়ত করে এক বা তিনবার তালবিয়া পড়ে নিন Continue reading “ওমরাহর নিয়ম” »


Testing Freeradius of Pfsense

FreeRADIUS offers an easy to use command line tool to check if the server is running and listening to incoming requests. Aninterface, a NAS/Client and a user must all be configured:

  • Add a User with the following configuration:Username: testuser
    Password: testpassword
  • Add a Client/NAS with the following configuration:IP-Address:
    Shared Secret: testing123
  • Add an interface with the following configuration:IP-Address:
    Interface-Type: Auth
    Port: 1812
  • SSH to the pfSense firewall and type in the following on the command line while FreeRADIUS is running (check before in System Log):
    radtest testuser testpassword 0 testing123

The following output should appear if everything was setup correctly: Continue reading “Testing Freeradius of Pfsense” »


Converting laptop into a wifi router

Well, first assuming, that the laptop has 2 NIC- one with an ethernet port for wired and the other- of course the Wifi ethernet (without this presume this content won’t exist otherwise 😉 )

Now, the next thing- either you get internet from the wired port or to be in some case, you may connect your android phone as wireless tethering and connect through mobile data service. Whatever the case- you basically got 2 interface for setting up the router- the WAN (either the wired or the mobile tethered connection) and the LAN- the wifi ethernet.

This document works good on Windows 7 and 8 (I didn’t test other editions of windows- hope they support too) Continue reading “Converting laptop into a wifi router” »


Business Server- How should it be

So, what would be a business on premise server look like…? Tried to build a feature based composition, but I guess need more upgradations-

  • Server operating system- Ubuntu 12.04 LTS
  • Network Firewall- ufw *
  • DNS server- Dnsmasq
  • DHCP server- ISC DHCP
  • Internet sharing with proxy and cache control, including reporting and user access control- Squid | Sarg
  • Anti-Virus and Anti-Spam ClamAV | AMaViS | SpamAssassin
  • Groupware Email, Contacts, Calendar, Webmail, with native Microsoft Outlook compatibility and mobile device support- SOGo *
  • Instant Messaging, VOIP and Video Chat server- Openfire | Spark *
  • Shared Printers and Files- Samba
  • Webserver Apache *
  • FTP server- ProFTP *
  • Database server- MySQL *
  • VPN- LogMeIn Hamachi  | Haguichi *
  • Virtualization support- Oracle VM VirtualBox *
  • Network Backup- RAID1 NAS *
  • Cloud Backup- Ubuntu One *
  • Remote Desktop Administration- x11vnc *
  • Remote Web Administration- Webmin
  • System Monitoring- Automatic Security Updates

All suggestions are welcome :)


Understanding RAID

I always try to share what I learn, and a few days back was looking for a single page short cut summary notes on various RAID level for the storage units. Found this article quite resourceful and exactly a single paged document that I was looking for.

Now sharing the content for the readers. Enjoy!


raid-0 (1)RAID 0 splits data across drives, resulting in higher data throughput. The performance of this configuration is extremely high, but a loss of any drive in the array will result in data loss. This level is commonly referred to as striping.

  • Minimum number of drives required: 2
  • Performance: High
  • Redundancy: Low
  • Efficiency: High

Continue reading “Understanding RAID” »


TeamViewer for Headless Linux Unattended System Access

Googled for hours, couldn’t found a solid documentation on this. After many different stitching material- prepared a little moderate installation (at least it worked for me). My Linux OS is Debian 8.x- believe should work in other debian version and Ubuntu as well. But, before continuing this, make sure-

  1. You have a teamviewer account
  2. The workstation (assuming a windows client pc) has a teamviewer client program installed to access the headless remote linux system.

Continue reading “TeamViewer for Headless Linux Unattended System Access” »


Nginx- Allow Directory browsing

Enabling directory listing in a folder in nginx is simple enough with just an autoindex on;directive inside the location directive. You can also enable sitewide directory listing by putting it in the server block or even enable directory access for all sites by putting it in the http block.

An example config file:

server {
 listen 80;
 access_log /var/...........................;
 root /path/to/root;
 location / {
 index index.php index.html index.htm;
 location /somedir {
 autoindex on;

Understanding Virtualbox network interfaces

To create and experiment with all kinds of networks without the risk (or taking the trouble) of creating an actual one. And here is where VirtualBox excels by providing several options for networking out of the box. VirtualBox installs an additional NIC (Network Interface Card) on your host computer to identify itself while communicating with the guest. By default the host gets an IP address of You can change the network modes, IP and other network settings by right-clicking your virtual machine on the left and clicking Settings. These are the networking modes that work with VirtualBox guest computers:

NAT (Default)
Host-only Network (Most secure)
Bridged Network (Least secure)
Internal-Network (Betweeen guests only)
Not Attached (No connectivity, guest isolated)
NAT: By default, the networking mode for your virtual machine is NAT (Network Address Translation) mode. This works something like this: Continue reading “Understanding Virtualbox network interfaces” »


Remote Administering pfsense

To open the firewall GUI up completely, create a firewall rule to allow remote firewall administration – do not create a port forward or any other NAT configuration.

Example Firewall Rule Setup

  • Firewall > Rules, WAN Tab
  • Action: pass
  • Interface: WAN
  • Protocol: TCP
  • Source: Any (or restrict by IP/subnet)
  • Destination: WAN Address
  • Destination port range: HTTPS (Or the custom port)
  • Description: Allow remote management from anywhere (Dangerous!)

Continue reading “Remote Administering pfsense” »