How to create a horizontal drop down menu in CSS
Written by A.Jesin Wednesday, 2 November 2011 10:11
Its been a long time since I wrote an article in this category (Web Design) so I decided to write an article on creating a horizontal drop down menu purely with HTML and CSS. To create a simple menu see CSS Horizontal Navigation Menu. Since the horizontal drop down menu uses only CSS and HTML it doesn’t work with Internet Explorer 6. The whole drop down menu concept makes use of the CSS pseudo class :hover, when you place the mouse pointer over a parent menu the CSS “display” attribute changes to “block” and displays the drop down menu, when you move the mouse pointer away from the menu the “display” attribute changes to “none” so the drop down menu disappears. Read More…
How to setup an unmanaged Debian server
Written by A.Jesin Sunday, 30 October 2011 10:42
So you’ve bought a shiny new VPS or dedicated unmanaged server to cut costs on hosting but don’t know how to begin ? Read this post to make this easirer. This tutorial will cover the instructions for a basic setup of a Debian unmanaged VPS or dedicated server. The following are covered in this article
- Configuring the Timezone
- Selecting locales
- Creating a sudo user
- Securing SSH
- Adding firewall rules
The first task is to update the apt database and check if any installed packages can be upgraded.
apt-get update && apt-get upgrade
How to use MSMTP with Gmail, Yahoo and PHP Mail
Written by A.Jesin Monday, 24 October 2011 09:26
This is a three in one tutorial which combines how to use MSMTP to send mails via Gmail and Yahoo servers and how to use MSMTP with PHP Mail() function instead of the default sendmail.
Installing msmtp
To install msmtp on Red Hat/CentOS/Fedora type of distributions
yum install msmtp
To install msmtp on Debian/Ubuntu type of distributions
apt-get install msmtp
Configuring msmtp with Gmail and Yahoo
Create or edit the msmtp configuration file in the user’s home directory. I use VI editor to achieve this
vi ~/.msmtprc
Add the following lines to the file, it configures msmtp for both Gmail and Yahoo
account yahoo
tls on
tls_starttls off
auth on
host smtp.mail.yahoo.com
user user1
from user1@yahoo.com
password ******
account gmail
tls on
auth on
host smtp.gmail.com
port 587
user user1@gmail.com
from user1@gmail.com
password ******
Since the file contains sensitive data like passwords you should assign secure permissions
chmod 600 ~/.msmtprc
Read More…
How to save IPtables rules in Debian
Written by A.Jesin Saturday, 22 October 2011 02:15
This article explains how to make IPtables firewall rules sustain a boot in Debian. But this can also be applied on other Debian based OSes like Ubuntu and Knoppix. You show execute all these commands as the root user or use the sudo command to do it.
First view the list of rules in IPtables
iptables -L
If its a new installation there will be no rules. So add some firewall rules, the following rules will allow HTTP, HTTPS, FTP, SMTP, SSH incoming connections and rejects all other incoming connections including ICMP ping packets.
iptables -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
iptables -A INPUT -i lo -j ACCEPT
iptables -A INPUT -m state --state NEW -p tcp --dport 80 -j ACCEPT
iptables -A INPUT -m state --state NEW -p tcp --dport 443 -j ACCEPT
iptables -A INPUT -m state --state NEW -p tcp --dport 21 -j ACCEPT
iptables -A INPUT -m state --state NEW -p tcp --dport 25 -j ACCEPT
iptables -A INPUT -m state --state NEW -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -j REJECT
View the firewall rules once more
iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED
ACCEPT all -- anywhere anywhere
ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:www
ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:https
ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:ftp
ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:smtp
ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:ssh
REJECT all -- anywhere anywhere reject-with icmp-port-unreachable
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Write these rules to a file using the following command.
iptables-save > /etc/iptables.rules
Now each time Debian boots iptables-restore command has to be called with these rules, so create and edit a new file as shown below. This file does NOT exist and you have to create it. I’m using VI editor to edit it
vi /etc/network/if-pre-up.d/firewall
Add the following text to that file
#!/bin/bash
/sbin/iptables-restore < /etc/iptables.rules
Save the file and grant executable permissions on that file.
chmod +x /etc/network/if-pre-up.d/firewall
Reboot the system and list the iptables rules to check if it has been applied.
reboot
After reboot
iptables -L
IMPORTANT: Whenever you add or delete rules you should overwrite the changes to the iptables.rules file using the following command
iptables-save > /etc/iptables.rules
How to assign a static IP address in Linux
Written by A.Jesin Monday, 17 October 2011 03:21
This article explains assigning a static IP to your Linux machine through the command line. If you’re assigning a public IP address, you should’ve purchased it from your ISP. Assigning the IP address in Linux requires you to edit the network configuration file. The network interface files are located at different places according the Linux OS variant. This article will cover both Red Hat and Debian variants. You need to logged in as the root user to edit these files, or you should have sudo permissions. Read More…
Windows devmgr_show_nonpresent_devices
Written by A.Jesin Tuesday, 11 October 2011 11:10
This tip will show the non present devices in windows operating systems. When a device is plugged the driver for that device is installed for the proper functioning of that device, but later when you unplug it the device entry disappears from the Device Manager but the drivers still exist in the system. This becomes a hindrance in some situations. Recently I myself came across the error “Cannot rename this connection. A connection with the name you specified already exists. Specify a different name.” when renaming a LAN connection, even though there was no other connection by that name. This was because earlier I had an Ethernet card with a connection by that name, even after the card was removed the operating system refused to forget it :). So applying this trick worked for me Read More…
